DETERMINATION OF MERCURY AND MERCURY

EXPOSURE IN PAKISTAN

A THESIS SUBMITTED TO

UNIVERSITY OF THE PUNJAB

FOR THE AWARD OF DEGREE OF

DOCTOR OF PHILOSOPHY

by

ZAIGHAM ABBAS

SUPERVISOR:

Prof. Dr. MUHAMMAD NAWAZ CH.

College of Earth and Environmental Sciences University of the Punjab, Quaid-e-Azam Campus,

Lahore – Pakistan

2014

i

DEDICATED

TO

My Loving Family Specially My Sweet

Daughter Sibgha Abbas

Their prays and guidance helped and enabled

me to

ACCOMPLISH THIS RESEARCH

ii

DECLARATION CERTIFICATE

This thesis which is being submitted for the degree of Ph.D. in the University of the Punjab

does not contain any material which has been submitted for the award of Ph.D. degree in

any University and to the best of my knowledge and belief, neither does this thesis contain

any material published or written previously by another person, except when due reference

is made to the source in the text of the thesis.

(Zaigham Abbas)

Ph.D. Scholar

College of Earth and Environmental Sciences

University of the Punjab

Lahore

iii

ACKNOWLEDGEMENTS

All praises to the Almighty Allah who induced the man with intelligence,

knowledge, sight to observe, mind to think and judge. Peace and blessings of Allah be upon

the Holy Prophet (PBUH) and his pure and pious progeny who exhorted his followers to

seek knowledge from cradle to grave.

I owe my heartfelt thanks to my worthy supervisor Prof. Dr. Muhammad Nawaz

Chaudhary (Professor Emeritus). Whose knowledge, skillful guidance, encouragement

and kindness have helped me in each and every stage of my research work. Indeed it is an

honor and pleaser for me to work with him.

I am also grateful to the Prof. Dr. Firdous-e-Bareen, Principal College of Earth &

Environmental Sciences, University of the Punjab, Lahore. I am thankful to Mr. Waheed uz

Zaman Scientific Officer, Institute of Chemistry, University of the Punjab, Lahore for

providing me research facilities during my research work. I would like to thank fellows of

Department of Chemistry, University of Aberdeen, Scotland, UK and UNEP Chemicals

Branch, Geneva, for providing me the necessary funds and advanced laboratories for

carrying out my research project.

I can never forget the prayers and untiring efforts of my parents, brothers and

sisters, who guided me and prayed for me in every step of my life.

In the last I want to thank my friends, Colleagues and labs fellows including Mr.

Abid Ali, Mr. Muhammad Ashraf, Ms. Khalida Bashir, Iqbal Hussain, Arshad Mahmood

Muzafar Majeed and Imran for their good wishes and moral support during the course of

my research work.

Zaigham Abbas

iv

ABSTRACT

The overall aim of this study was to identify and quantify mercury releases in

Pakistan. It was observed that most of the waste water and solid samples collected from all

the four provinces of the country, show mercury contamination. Although the results are

lower than NEQS limits but only marginally. It also reflects that all the sectors of society

and industry have exposure to mercury. This study was focused only on limited industries

as well as industrial, sewerage effluents and solid waste sites.

The maximum mercury concentration was found at the solid waste disposal sites in

all areas of provinces of Pakistan. These high results are due to the dumping of mercury

and its compounds in municipal and industrial waste without prior segregation. However,

this value of mercury is dangerous for humans as well as a disaster for aquatic life. The

proper disposal or removal of mercury from the solid waste could be a reliable mitigation

measure for the toxicity of mercury.

This study was also focused on the determination of mercury in exposed people. It

can be seen that in human hair sample groups 1, 2 and 3, most of the hair samples (T-Hg

concentration) exceed the normal value (2.0 µg/g) recommended by the WHO (1990). This

can be related to prolonged exposure of workers to the mercury vapour. Apparently, longer

the duration of exposure, higher the value of total mercury (T-Hg) found in their hair

samples. For example, in group No.1, the workers come into contact with mercury and

mercury vapour at the work place (Ittehad Chemicals Limited employing chlor-alkali

process using mercury cell technology) thus resulting in high concentration of T-Hg in

their hair samples.

In group No.2 were the workers of the factory who have completely phased out

mercury cell technology. The high concentration of T-Hg in hair samples of these workers

might be due to exposure to the contaminated areas. The group No. 3 in close vicinity to

mercury usage has an even lower level of mercury, owing to better occupational practices

and proper knowledge. However, in group No.4, lower concentrations of total mercury in

hair samples were recorded as a result of limited exposure to mercury involving students

v

and staff at Punjab University, Lahore.

It is for the first time in the history of Pakistan that a preliminary study on the issue of

the use and release of mercury in the country has been carried out for its use as a key

document for nationally sound management of mercury release. In this study area, the

responsible stakeholders of concerned ministries, their line agencies and local authorities

were involved in conducting survey on mercury use and release sources in all the four

provinces of Pakistan.

While carrying out the survey at the concerned ministries, provincial departments,

local authorities and various sites, many problems were faced regarding critical gaps in

making and keeping statistical records, such as lack of reliable data and information from

various generating/releasing sources. In this regard, most data/information was obtained by

estimations made by local line institutions and as a result, some difficulty was faced in

calculating actual levels of the release of mercury into the environment. Despite these

challenges, the survey activities have sensitized the stakeholders on mercury issues and

related harmful effects to human health and the ecosystem. Nevertheless, a concerted effort

was made in obtaining and calculating the release of quantity of mercury into the

environment and it is concluded that the total quantity of mercury released in Pakistan is:

Maximum emission and transfer: 36898 Kg per year

Minimum emission and transfer: 10842 Kg per year

This study is the first step which would prove a milestone towards conducting a

full-fledged assessment covering all the sectors in due course of time. For such a full

inventory, it will be necessary to collect all information from various sectors/fields as

specified in categories and sub-categories addressed in the UNEP’s Toolkit, which reflects

Pakistan’s context.

This mercury inventory will assist the decision makers of the country in the sound

management of mercury leading to the provision of benefits for not only the existing

generation but also the future generations.

vi

ABBREVIATIONS

UNEP United Nations Environment Programme

WHO World Health Organization

ATSDR Agency for Toxic Substances and Disease Registry

RPA Risk and Policy Analysis Limited

USGS United States Geological Survey

EC European Commission

Me-Hg Methyl mercury

US EPA United States Environmental Protection Agency

NJ MTF New Jersey Mercury Task Force

ESPs Electrostatic Precipitators

OECD Organization for Economic Cooperation and Development

B.P Blood Pressure

EPAs Environmental Protection Agencies

NGOs Non-Government Organizations

PPM Parts Per Million

vii

TABLE OF CONTENTS Dedication i

Declaration Certificate ii

Approval Certificate

Acknowledgment iii

Abstract iv

Abbreviations vi

Table of Contents vii

List of Tables x

List of Figures xiii

INTRDUCTION ------------------------------------------------------------------------------------ 1

1.1. Historical background -------------------------------------------------------------------------- 2

1.2. Chemistry ---------------------------------------------------------------------------------------- 3

1.3. Production, uses and environmental fate ---------------------------------------------------- 4

1.3.1. Production ------------------------------------------------------------------------------------- 4

1.3.2. Uses ----------------------------------------------------------------------------------------- 6

1.3.3. Environmental fate --------------------------------------------------------------------------- 6

1.3.3.1. Atmosphere --------------------------------------------------------------------------------- 6

1.3.3.2. Soil ------------------------------------------------------------------------------------------- 7

1.3.3.3. Vegetation ---------------------------------------------------------------------------------- 8

1.3.3.4. Aquatic systems, sediments and methylation ------------------------------------------ 8

1.4. Objectives of the study ----------------------------------------------------------------------- 11

REVIEW OF LITERATURE ------------------------------------------------------------------- 13

2.1 Sources and releases of mercury ------------------------------------------------------------- 13

2.2 Uses of mercury and mercury compounds -------------------------------------------------- 23

2.3 Mercury exposure ------------------------------------------------------------------------------- 28

MATERIALS AND METHODS --------------------------------------------------------------- 33

3.1. Identification and quantification methodology -------------------------------------------- 33

viii

3.1.1. Identification of mercury releases --------------------------------------------------------- 35

3.1.2. Quantification of mercury releases -------------------------------------------------------- 35

3.2. Collection of samples-------------------------------------------------------------------------- 36

3.2.1. Waste water and soil samples -------------------------------------------------------------- 36

3.2.2. Hair samples ---------------------------------------------------------------------------------- 36

3.3. Preparation of samples ------------------------------------------------------------------------ 37

3.3.1. Waste water sampling ----------------------------------------------------------------------- 37

3.3.2. Sampling of soil matrices ------------------------------------------------------------------- 37

3.3.3. Hair sample preparation -------------------------------------------------------------------- 38

3.4.Techniques used for determining of mercury ----------------------------------------------- 39

3.4.1 Method of Cold Vapour Atomic Absorption Spectroscopy (CV-AAS) -------------- 39

3.4.1.1. Chemical reagents ------------------------------------------------------------------------ 40

3.4.1.2. Glassware ---------------------------------------------------------------------------------- 40

3.4.2 Cold Vapour Atomic Fluorescence Spectrometry (CV-AFS) ------------------------- 40

3.4.2.1. Chemical reagents ------------------------------------------------------------------------ 41

3.4.2.2. Glassware ---------------------------------------------------------------------------------- 41

3.4.2.3. General operation procedure ------------------------------------------------------------ 41

3.5. Analytical performance characteristics ----------------------------------------------------- 42

3.5.1 Quality control -------------------------------------------------------------------------------- 42

3.5.2. Limit of detection (L.O.D) ----------------------------------------------------------------- 42

3.5.3 Calibration data ------------------------------------------------------------------------------- 43

RESULTS AND DISCUSSION ----------------------------------------------------------------- 44

4.1 Results of waste water and solid samples from the country ---------------------------- 45

4.1.1 Discussion ------------------------------------------------------------------------------------- 52

4.2 Results of mercury from human hair samples ---------------------------------------------- 52

4.2.1. Comparison with other studies ------------------------------------------------------------- 61

4.3. Data from the markets of Lahore, Karachi, Quetta, Kasur, Rawalpindi and Research

Institutes ---------------------------------------------------------------------------- 64

ix

4.4. Quantification of mercury releases ---------------------------------------------------------- 69

4.4.1 Natural gas - extraction, refining and use ------------------------------------------------ 72

4.4.2. Primary metal production-small scale gold mining ------------------------------------ 73

4.4.3. Production of other minerals and materials with mercury impurities ---------------- 74

4.4.4 Intentional use of mercury in industrial processes --------------------------------------- 75

4.4.5 Consumer products with intentional use of mercury ------------------------------------ 78

4.4.6 Other intentional products/process uses --------------------------------------------------- 84

4.4.6.1 Source description ------------------------------------------------------------------------- 84

4.4.7 Production of recycled metals (secondary metal production) -------------------------- 86

4.4.8 Waste incineration ---------------------------------------------------------------------------- 86

4.4.9 Waste deposition/land filling and waste water treatment ------------------------------- 89

4.4.9.1. Controlled landfills sites ----------------------------------------------------------------- 89

4.4.9.2. Informal waste disposal ------------------------------------------------------------------ 91

4.4.9.3. Waste water treatment ------------------------------------------------------------------- 92

4.4.10 Crematoria and cemeteries ---------------------------------------------------------------- 93

4.4.11 Identification of potential hot-spots ------------------------------------------------------ 93

4.5.Overview of the mercury inventory results ------------------------------------------------- 94

4.6.Overall Conclusion --------------------------------------------------------------------------- 100

CONCLUSIONS AND RECOMMENDATIONS ---------------------------------------- 102

5.1. Conclusions ----------------------------------------------------------------------------------- 102

5.2. Recommendations --------------------------------------------------------------------------- 104

REFERENCES ----------------------------------------------------------------------------------- 106

APPENDICES

x

LIST OF TABLES

Table 1: Determination of T-Hg in CRM NIES -13& CRM IAEA 085 -------------------- 42

Table 2: Calibration data for mercury ------------------------------------------------------------ 43

Table 3: Results of samples from Sindh (Karachi etc) ----------------------------------------- 45

Table 4: Results of samples from Punjab (Lahore, Sheikhupura, Faisalabad etc) --------- 47

Table 5: Results of samples from Baluchistan (Quetta etc) ----------------------------------- 49

Table 6: Results of samples from N.W.F.P (Peshawar etc) ----------------------------------- 50

Table 7:Total mercury concentration in human hair samples of workers in Ittehad

Chemicals Limited, Kala Shah Kaku ---------------------------------------------------- 53

Table 8:Total mercury concentration in human hair samples of workers in Sitara

Chemicals Industries Limited, Faisalabad ---------------------------------------------- 54

Table 9: ----- Total mercury concentration in human hair samples of technicians/doctors in

Punjab Dental College and Hospital, Lahore ------------------------------------------ 55

Table 10:Total mercury concentration in human hair samples of students and staff of

Punjab University, Lahore ---------------------------------------------------------------- 56

Table 11:Comparison of T-Hg concentrations from this study with other different studies

of different exposed populations worldwide ------------------------------------------- 62

Table 12: Cheap Chemicals Store, Lahore ------------------------------------------------------ 64

Table 13: Akbari Chemicals Store, Lahore ------------------------------------------------------ 64

Table 14: Merck (Pvt.) Ltd, Lahore -------------------------------------------------------------- 65

Table 15: Nawab Chemical Store, Karachi ------------------------------------------------------ 65

Table 16: Dawawala Chemical Corporation, Karachi ----------------------------------------- 65

Table 17: Mohammad Jamil Sons, Karachi ----------------------------------------------------- 65

Table 18: Rahat Chemicals, Quetta --------------------------------------------------------------- 65

Table 19: Alam Instruments & Chemicals, Quetta --------------------------------------------- 66

Table 20:Kasur Tannery Waste Management Agency (KTWMA), Kasur ----------------- 66

xi

Table 21:Shalimar Scientific Store, Rawalpindi ------------------------------------------------ 66

Table 22: Scientific Home, Rawalpindi ---------------------------------------------------------- 66

Table 23: Nobel Scientific Traders, Rawalpindi ------------------------------------------------ 67

Table 24: Medi Plus Chemist, Rawalpindi ------------------------------------------------------ 67

Table 25: Shaheen Chemist, Rawalpindi -------------------------------------------------------- 67

Table 26: Khattak Chemist, Rawalpindi --------------------------------------------------------- 67

Table 27: City Surgical, Rawalpindi ------------------------------------------------------------- 68

Table 28: The Mall Chemist, Rawalpindi ------------------------------------------------------- 68

Table 29: W. Watson Chemist, Rawalpindi ----------------------------------------------------- 68

Table 30: Institute of Chemistry, University of the Punjab, Lahore ------------------------- 68

Table 31: Pakistan Council for Scientific and Industrial Research (PCSIR), Lahore ----- 69

Table 32: Local production of coal in Pakistan (July 07 to 30 June, 2008) ----------------- 70

Table 33: Toolkit calculation for mercury releases from coal sector ------------------------ 70

Table 34: Toolkit calculation for mercury releases from extraction of crude oil ---------- 71

Table 35: Toolkit calculation for mercury releases from use of gasoline, diesel and other

distillates ------------------------------------------------------------------------------------- 72

Table 36: Toolkit calculation for mercury releases from natural gas ------------------------ 73

Table 37:Toolkit calculation for mercury releases from cement production --------------- 75

Table 38: Chlor-alkali industry in Pakistan ----------------------------------------------------- 76

Table 39: Toolkit calculation for mercury releases from chlor-alkali sector --------------- 77

Table 40: Toolkit calculation for mercury releases from thermometer with mercury ----- 79

Table 41: Toolkit calculation for mercury releases from fluorescent tubes (double end) 80

Table 42: Toolkit calculation for mercury releases from metal halide lamps -------------- 81

Table 43: Toolkit calculation for mercury releases from alkaline, other than button cell

shapes ---------------------------------------------------------------------------------------- 82

xii

Table 44: Toolkit calculation for mercury releases from mercury oxide (all sizes) also

called mercury-zinc cells ------------------------------------------------------------------ 83

Table 45: Toolkit calculation for mercury releases from other intentional product/process

use -------------------------------------------------------------------------------------------- 85

Table 46: Quantity of medical waste incinerated per year ------------------------------------ 87

Table 47: Toolkit calculation for mercury releases from medical waste incineration ----- 88

Table 48: Toolkit calculation for mercury releases from controlled landfills/deposits --- 90

Table 49: Toolkit calculation for mercury releases from informal dumping of general waste

------------------------------------------------------------------------------------------------ 91

Table 50: Toolkit calculation for mercury releases from waste water treatment ---------- 92

Table 51: Summary of mercury release from all categories ---------------------------------- 94

Table 52: Type of mercury release per category ------------------------------------------------ 96

xiii

LIST OF FIGURES

Fig.1: Global Annual Mercury Mining Production --------------------------------------------- 5

Fig 2: Schematic diagram of continuous flow vapour generator and AFS detector.

(Modified from PS Analytical 10.125 Millennium Excalibur, User Manual .Issue No 2.2)

--------------------------------------------------------------------------------------------------------- 41

Fig 3:Concentration of T-Hg (µg/g) in human hair samples ranked for their concentration.

--------------------------------------------------------------------------------------------------------- 57

Fig.3a: Concentration of T-Hg (µg/g) in human hair samples (n=72). The line indicates the

WHO value of 2 µg/g. ------------------------------------------------------------------------------ 57

Fig. 3b: Concentration of T-Hg (µg/g) in human hair samples (n=72). CA1 is Ittehad

Chemicals, Sheikupura; CA2 is Sitara Chemicals, Faisalabad. Dental represents the

samples from workers in dental surgery facilities. --------------------------------------------- 58

Fig. 4: Location of study area in Punjab Province, Pakistan ---------------------------------- 59

Fig. 5: Mercury input in environment ------------------------------------------------------------ 96

Fig.6: Total mercury releases in air (Kg per year) ---------------------------------------------- 97

Fig.7: Mercury releases in water (Kg per year) ------------------------------------------------- 97

Fig.8: Mercury releases in land (Kg per year) -------------------------------------------------- 98

Fig 9: Regional mercury consumption (2005) -------------------------------------------------- 99

1

CHAPTER 1

INTRDUCTION

Mercury and mercury compounds exist in the globe and are stable in the

atmosphere. Mercury is found in the natural form that is liberated due to usual phenomena

as well as anthropogenic activities. Once mercury is exposed into the atmosphere, it

changes into a range of chemical and physical transformations amongst atmosphere,

lithosphere and hydrosphere. Humans, plants, and animals usually get exposed to mercury

and gather it during this biogeochemical cycle which might affect various health impacts

(UNEP, 20021).

According to WHO, 1990, 19912-3

, ―mercury and mercury compounds are harmful

substances that are categorized in the main cluster of environmental pollutants. The

hazardousness of mercury and mercury compounds depend on chemical structure.

Inhalation of mercury vapor and intake of methyl mercury are the two major routes of

human revelation to mercury. Workers are exposed to mercury in industry and business

during mercury mines, gold mining where Hg is used for gold recovery, mercury

dispensing and sales and thermometer manufacturing factories and dental clinics‖. One of

the significant source of human exposure to elementary mercury is dental amalgam filling

(Clarkson, 1988)4.

Mercury occurs in inorganic, organic and elemental forms. At ordinary temperature

and pressure metallic mercury exist in liquid form. Metallic mercury is potential source of

vapors in air. A large amount of mercury is found in the form of elemental mercury vapor

in the environment. In other spheres, apart from environment, inorganic mercury salts and

organomercurials predominate.

Inorganic mercury compounds are used in a number of manufacturing processes.

Mercury compounds have been extensively employed in batteries and various other

products including fungicides, sanitizers or disinfectants. Numbers of mercury compounds

are available, though, methyl mercury is most known in the foodstuffs and atmosphere.

Organic mercury compounds are known for their use as fungicides and in pharmaceutical

compounds like mercurochrome are used topical antiseptics likewise thiomersal are

employed for their use as a preservative in vaccines. The salts of phenyl mercury have been

2

used as pharmaceutical, fungicides and in cosmetics to hinder the propagation of

micro-organisms. Phenyl mercury acetate had been used in paint as a preservative. Ethyl

mercury, methyl mercury and phenyl mercury occur mostly as acetates and chlorides.

According to ATSDR, 19995, ―the inhalation of mercury vapor, intake of mercury

contaminated drinking water and exposure to mercury through medical treatments may

impact animals and humans. Intake through food is the main source of unintentional and

non-professional exposures to mercury‖.

1.1. HISTORICAL BACKGROUND

Mercury, also known as quicksilver, is a heavy, silvery-white metal (D=13.56)

which is liquid at room temperature and evaporates easily. In nature, it is usually found in

the form of cinnabar (HgS), used in the past as a red pigment. Cinnabar deposits have been

mined for centuries to produce mercury. However, mercury minerals may occur associated

with deposits of other metals such as lead and zinc and mercury may be produced as a

byproduct. Mercury may also be found in small amounts in a wide range of rocks including

coal and limestone. Mercury can be released into the air, water and soil through

anthropogenic as well as natural sources.

Mercury has been used since antiquity. Archaeologists have recovered traces from

Mayan tombs and from the remains of Islamic Spain (Bank, 2012 6). The first emperor of

unified China is said to have died after ingesting mercury pills intended to give him eternal

life (Asia History website). Metallic mercury is still used in some herbal and religious

remedies in Latin America, Asia and Caribbean rituals (ATSDR, 1999 5).

Mercury was discovered from Egyptian tombs as old as 1500 BCE7. Earlier in

Tibet and China, mercury was intended to treat fractures, provide good health and prolong

life8. Mercury was an important constituent of ointments used by ancient Greeks. Use of

mercury in cosmetics dated back to old Egyptians and Romans where it rarely faded the

face 9-10

.Whereas significance of mercury in ancient metallurgy can be visualized by their

use in making amalgams with other metals in 500 BC11

. The Indian word for alchemy is

―rasavātam‖ which meant for "the way of mercury‖ 12

.

Alchemists regarded mercury as the mother of all elements i.e. altering the quality

and quantity of sulfur present with mercury other metals could be synthesized. The main

3

focus of the alchemists was to alter the impure metals to gold. Mercury is the only metal

for which the alchemical terrestrial name became the common name13

.

Hg is the symbol for mercury stands for hydrargyrum, that is Latinized form of the

Greek word Ύδραργσρος (hydrargyros) which is a hybrid meant for "water" and "silver‖.

This is in allusion to the fact that mercury is a liquid like water and it possess silver metallic

sheen14

. The name mercury is given after the name of Roman god (linked with planet

mercury) which is related to swiftness and mobility.

The oldest mine around 2500 years ago in Europe was the Almadén mine of Spain

followed by other important mines namely Monte Amiata (Italy) and Idrija (now

Slovenia). These three mines remained the major focus for production in Almadén about

2500 years ago until new deposits were explored at the end of 19th

century15

.

Use of mercury in making pools was reported from Islamic Spain, Later on,

Alexander Calder an American artist, in 1973 at the World Exhibition in Paris fabricated a

mercury fountain for the Spanish Pavilion which is at present on display at Fundació Joan

Miró in Barcelona16

.

In making of felt hats from the mid-18th to the mid-19th centuries "carroting" was

used where an orange coloured compound mercuric nitrate, Hg (NO3)2·2H2O, was used for

rinsing animal skins to separate the hairs from the skin of animals and to tangle hairs

together17

. The solution used was highly toxic and produce strong vapours. Thus it was

banned by the United States Public Health Service in the felt industry by December 1941.

Elemental mercury has unique characteristics. It is liquid at room temperature,

good electrical conductor, very high density and high surface tension. It is the only liquid

metal that is used in a large number of products and procedures exploiting its unique

characteristics.

1.2. CHEMISTRY

According to Cotton and Wilkinson, 198818

, ―mercury occurs in three valence

states: elemental mercury (also known as metallic mercury, Hg0), mono-valent mercurous

(Hg2++

), and the divalent mercuric (Hg++

). Elemental mercury is the most stable form and

does not react readily with oxygen or water‖ Mercuric and mercurous mercury are

thermally unstable. They decompose readily to elemental mercury under heat, light

4

exposure and treated with reducing agents. Hg0 is only merely soluble in water. However

greater solubility is observed in organic solvents as compare to water. Elemental mercury

could be source of vapors even at room temperature posing hazard during spillages‖.

The main mineral of mercury is cinnabar (HgS) which is water insoluble. Hg++

has

generally high affinity for sulfur and mercaptans. Elemental mercury reacts with elemental

sulfur and hydrogen sulfide (but not mercaptans) (Nowak and Singer, 200019

, Wilhelm et

al., 200620

). Humic compounds in sediments, soil and water form stable complexes with

Hg++

which are relatively least effected by change in pH (Jackson, 199821

, Skyllberg et al.,

200622

). Another mercury compound namely mercuric chloride (HgCl2) is covalent and

linear molecule in its aqueous as well as organic solvent solutions (Greenwood and

Earnshaw, 199723

). According to Nowak and Singer, 200024

, ―HgCl2 is soluble in water as

well as in some organic solvents‖.

According to Jackson, 199821

, ―halides of methyl mercury, as well as together with

dimethyl mercury are linear molecules like HgCl2. Organometallic Hg++

compounds are

resistant to oxidation and hydrolysis and are kinetically stable in water and O2‖. ―The

chemical affinities of methyl mercury for ligands, including organic matter, is equivalent

to Hg++

but the stability constants of methyl mercury complexes with these ligands are

always lower than for the corresponding Hg+2

complexes. Furthermore, unlike Hg+2

,

methyl mercury easily and quickly exchanges one thiol group for another‖ (Jackson,

199821

,Boudou et al., 199125

).

1.3. PRODUCTION, USES AND ENVIRONMENTAL FATE

1.3.1. Production

Mercury is a lithophil element. Its average crustal abundance is projected

approximately 0.05µg/g (DeVito, 200526

). The mercury content in mercury ores is around

one percent. However, mercury content is 12-14 percent in ores excavated from Spain.

Mercury in trace amounts is present throughout the biosphere. Mercury in coal, oil and gas

is manly derived from precursor, terrestrial and marine flora

According to UNEP, 20021, RPA, 2002

27, ―the Hg production has varied widely

since it came into use at about 2500 years ago. After the industrial revolution, the global

production peaked in the early 1970s at approximately 10,000 tons per year. In 2000, the

5

global production from Hg ores was about 2,000 tonnes/year which was supplement by

approximately2,000 tonnes/year as a byproduct of other metals‖.

The world production was estimated at about 4100 metric tons/year by USGS

(199028

) and 5356 metric tons/year according to Gobi International 199829

and Sznopek

and Goonan, 200030

). USGS (199631

) assessed the production of mercury at 2795 metric

tons whereas; according to Gobi International 199829

it is 3337 metric tons. The difference

in the reported amount is due to unknown reasons however it is estimated that the real

amount may be even higher. It could also be likely that recycled mercury, mercury

recovered as by-product or marketing from stocks have influenced the higher amount of

mercury.

Accordance to Lawrence, (200032

) ―on a worldwide basis, the amount of

by-product mercury was estimated at about 4000 metric tons per year‖.

Lawrence (200232

, as quoted by USA; comm-24-gov) projected world market

supply of mercury in 2002 ranging up to 2000 metric tons. Out of this total supply, the

virgin mercury extraction from all sources comprised about 1,000 metric tons, while

another roughly 1,000 metric tons of Hg comes from other sources.

Fig.1: Global Annual Mercury Mining Production

6

The difference in the reported amount is due to unknown reasons however it is

estimated that the real amount may be even higher. It could also be likely that recycled

mercury, mercury recovered as by-product or marketing from stocks have influenced the

higher amount of mercury.

1.3.2. Uses

The current global mercury demand estimated about 3,600 tonnes per year.

Mercury is greatly employed to be used in gold mining, batteries and the chlor-alkali plants

using mercury cells. These plants consume more than 75% of the global mercury (EC,

200533

). In 2003, the 15 Member States of the European Union consumed about 300 tonnes

per annum mercury (EC, 200533

) as against 448 tonnes per year in 1993 which works out at

about 11.7% of the global use (UNEP, 20021). Mercury finds wide use as dental amalgam.

Mercury is still being used in chlor-alkali production with mercury cell.

Vinyl-Chloride-Monomer (VCM) is used for the production of mercury dichloride (HgCl2)

as catalyst. Acetaldehyde production requires mercury sulphate (HgSO4) catalyst. Mercury

is used in thermometers, electrical switches and relays. Other consumers of mercury

include light sources with mercury, batteries with mercury, paints, pharmaceuticals for

human and veterinary uses, biocides and pesticides, cosmetics and related products, dental

mercury-amalgam fillings, manometers and gauges, laboratory chemicals and equipment,

mercury metal use in religious rituals and folklore medicine.

1.3.3. Environmental fate

1.3.3.1. Atmosphere

Mercury released from different sources enters the air in the form of vapors and

precipitation in considerable quantities and chemical species such as elemental mercury

and dimethyl mercury. According to Schroeder and Munthe, 199834

, ―mercury occurs in

ambient air as vapor.90-95% of vapor occurs as monoatomic gas (Hg0)‖. Small quantities

of mercury occur as particulate matter (Lindqvist et al., 199135

). Small amounts of mercury

occur as methyl mercury. This is between 1.5% of 5% of total mercury in precipitation.

According to Downs et al., 199836

, Lindqvist et al., 199135

, Glass and Sorensen, 199937

,

Grigal, 200238

), ―dimethyl mercury has also been found in air but it is assumed to be very

7

short-lived‖. Half-life of mercury is only a few hours thus; it oxidizes quickly (Niki et al.,

198339

, Lin and Pehkonen, 199940

).

According to Lamborg et al., 200241

, ―the global average level of mercury in the

atmosphere at present is 1.6 ng/ m3‖.The total mercury levels range between 1-50 ng/L

(Lindqvist et al., 199135

, Hall, 199542

, Downs et al., 199836

). However, reported volume

weight ranges from to 5-15 ng/L in unpolluted North Temperate areas (Grigal, 200238

).

Hg+2

following oxidation of elemental mercury is found in precipitation as a major form

(Munthe et al., 199143

Hall, 199542

,Lin and Pehkonen, 199940

). Reduction in Long term

mercury levels has been found through various studies in the atmosphere of Europe and

North-America during the last 20-30 years (Iverfeldt et al., 199544

Slemr and Schell,

199845

Kock et al., 200546

Steffen et al., 200547

Temme et al., 200748

,Wängberg et al.

200749

).

1.3.3.2. Soil

According to Skyllberg et al., 200650

, ―the main form of mercury found in soil is

Hg+2

‖.Complexing of Hg+2

with soil organic phases is the dominant process by which

mercury is fixed in soil. The most toxic form of mercury i.e. methyl mercury occurs is very

small proportion (at 0.01- 2% of the total mercury) (Lindqvist et al., 199135

Davis et al.,

199751

, Grigal, 200352

).The dimethyl mercury compared to methyl mercury occurs in very

low concentration. The dimethyl mercury is less than 1/1000 times of methyl mercury

(Davis et al., 199751

). Because of strong complexing of Hg with soil organic matter, it

retention time is long. The assimilated mercury thus potentially contribute to other media

for hundreds to thousands years (UNEP, 20021, Hissler and Probst, 2006

53).

Notwithstanding the fact that a significant range of mercury contents have been

reported from soils, most agricultural soils and the vegetation have very low values of

mercury. According to Archer and Hodgson, 198754

, ―an average range was 0.02 to 0.40

µg/g, the contents of mercury in excess are to be considered contaminated‖(Kabata-

Pendias, 200155

).

According to Schlüter, 200056

, Tack et al., 200557

, Rodrigues et al., 200658

, ―urban

soils contain quite variable but generally higher levels of mercury compared to

rural/agricultural soils. However, soils within the influence of natural or anthropogenic

emission sources are likely to contain very high levels of mercury‖.

8

1.3.3.3. Vegetation

Mercury plays no role in the metabolism of vascular plants. The roots of plants

retard mercuric mercury transport up the plant. The concentration of mercury in plants is

usually lesser than in water and soil (Grigal, 200238

, 200352

, Millhollen et al., 200659

). The

atmospheric route is the main source of mercury for plants (Grigal, 200352

, Ericksen et al.,

200360

, Rea et al., 200161

, Millhollen et al., 200659

). Mercury is taken from air as dry

deposition as well as in gaseous Hg0 form (and gaseous Hg

+2-compounds) (Grigal, 2002

38).

Again the plant transport system does not transmit mercury to other parts. At best the

transportation is to a very narrow range (Lindqvist et al., 199135

). According to Grigal,

200238

, 200352

, ―the relative proportions of methyl mercury to total mercury in plant

foliage, is generally comparable to that in precipitation. This would very strongly suggest

atmospheric derivation‖.

1.3.3.4. Aquatic systems, sediments and methylation

The aquatic environment contains mercury in different physical and chemical

forms. The chemical species that matter are differential complexes of the mercuric ion

formed with various ligands both organic and inorganic, methyl mercury, dimethyl

mercury and elemental mercury.

According to Ullrich et al., 200162

, ―speciation chemistry of the Hg+2

ion in oxidic

waters is dominated manually by organic complexes. In freshwater (oxygenated water)

more than 90% of Hg+2

is complexed by dissolved organic matter‖. Sulphides are the key

control in anoxic waters on the speciation chemistry of Hg+2

and methyl mercury (Jackson,

199863

).

According to Ullrich et al., 200162

, ―between 10 and 30% of dissolved mercury in

oceans and lake water is elemental mercury‖. During summer season, the surface waters

are mostly supersaturated with Hg0 in the context of water atmosphere equilibrium

(Gårdfeldt et al., 200164

, Anderson et al., 200765

).

According to Lindqvist et al., 199135

, ―methyl mercury containing up to 10% total

mercury in lake waters of Sweden have been reported‖. However, dimethyl mercury was

not found in detectable amounts (Ullrich et al., 200162

). Methyl mercury is usually between

10% to 40% of total mercury in ocean waters (Leermarkers et al., 200166

, Kotnik et al.,

200767

, Horvat et al., 200368

, Mason and Sullivan, 199969

, Mason et al., 199870

).

9

Formulation of methyl mercury in water and sediments usually takes place through

methylation process by biotic processes.

According to Kotnik et al., 200767

; Horvat et al., 200368

, ―dimethyl mercury at

<0.5% of total mercury in the Mediterranean Sea is found at depths below 20 to 40 m‖.

Sediment dimethyl mercury is known to form by methyl mercury in the presence of a

sulfide phase (Quevauviller et al., 199271

; Baldi et al., 199572

; Weber et al., 199873

; Stein et

al., 199674

).

The mercury level in uncontaminated freshwaters may generally in accounts <5

ng/L. Median values of 3.1 to 6.2 ng/L of mercury were reported in 25 Swedish lakes

(Lindqvist et al., 199135

). Higher concentrations 10 or 20 ng/L could be recovered in humic

lakes or rivers which are rich in particulate mercury (Ullrich et al., 200162

). The

concentration of mercury may reach up to μg/L range in contaminated water (Ullrich et al.,

200162

). The marine concentrations of mercury are much lower and range from 0.1 to 1

ng/L (Leermarkers et al., 200166

, Kotnik et al., 200767

, Horvat et al., 200368

, Mason and

Sullivan, 199969 ,

Mason et al., 199870

).

In aquatic systems methylation of mercury takes place. Due to this reason, water

dwelling life forms and fish eating birds and animals have usually higher levels of mercury

compared to terrestrial animals. No wonder the concentration of ethyl mercury increase

with trophic level and age. According to Dehn et al., 200675

, ―arctic zooplanktons contain

between 1 to 10 g/kg wet weight while top predators like beluga whale (toothed whale,

Delphinapterus leucas), polar bears (Ursus maritimus) and ringed seals (Phoca hispida)

may contain >10,000 g/kg in their livers‖. Livers and kidney of marine mammals contain

for more methyl mercury than other body parts. In muscle tissue, the main form of mercury

is methyl mercury. However due to a process of demethylation, the livers of many marine

mammals and seabirds show a decrease in methyl mercury with increase in total

concentration of mercury (Gaskin et al., 197976

, Falconer et al., 198377

, Chen et al., 200278

, Endo et al., 200479

, Thompson and Furness, 198980

, Wagemann et al., 199881

, 200082

).

The aforementioned statistics and data bring up clearly the fact the mercury has

significantly been entered in the environment through human industrial activities. It is not

only the environmental issue but directly and seriously related to the biological systems in

and around us. As the problem has been diagnosed and the data collected, now is the right

10

time to take serious steps towards reduction in production and release of mercury in

environment so that it no longer is a threat for earth’s eco system. The Minamata

Convention is one such effort where the global consensus is observed for the reduction and

finally elimination of mercury from industrial processes.

The Minamata Convention on Mercury is a global treaty to protect human health

and the environment from the adverse effects of mercury. It was agreed at the fifth session

of the Intergovernmental Negotiating Committee in Geneva, Switzerland on 19 January

2013.The Diplomatic Conference of Plenipotentiaries on the Minamata Convention on

Mercury and its preceding open-ended intergovernmental Preparatory Meeting were held

from 7-11 October 2013 in Kumamoto and Minamata, Japan. The Minamata Convention

on Mercury was officially opened for signature on 10 October, and in its first two days was

signed by 91 countries and the European Union. Currently, 100 countries signed and one

country ratified this Convention.

The major highlights of the Minamata Convention on Mercury include a ban on

new mercury mines, the phase-out of existing ones, control measures on air emissions, and

the international regulation of the informal sector for artisanal and small-scale gold mining.

The Convention draws attention to a global and ubiquitous metal that, while

naturally occurring, has broad uses in everyday objects and is released to the atmosphere,

soil and water from a variety of sources. Controlling the anthropogenic releases of mercury

throughout its lifecycle has been a key factor in shaping the obligations under the

Convention.

Under the provisions of the Minamata Convention, Governments have agreed on a

range of mercury-containing products whose production, import and export will be banned

by 2020. These items have non-mercury alternatives that will be further phased in as these

are phased out. They include:

Batteries, except for 'button cell' batteries used in implantable medical devices

Switches and relays

Some compact fluorescent lamps

11

Mercury in cold cathode fluorescent lamps and external electrode fluorescent

lamps

Soaps and cosmetics (mercury is used in skin-whitening products)

Some mercury-containing medical items such as thermometers and blood pressure

devices.

Mercury from small-scale gold-mining and from coal-fired power stations

represent the biggest source of mercury pollution worldwide. Miners inhale mercury

during smelting, and mercury run-off into rivers and streams contaminates fish, the food

chain and people downstream.

Under the Minamata Convention, Governments have agreed that countries will

draw up strategies to reduce the amount of mercury used by small-scale miners and that

national plans will be drawn up within three years of the treaty entering into force to reduce

- and if possible eliminate - mercury. The Convention will also control mercury emission

and releases from large-scale industrial plants such as coal-fired power stations, industrial

boilers, waste incinerators and cement clinkers facilities. Besides the Minamata

Convention, there is another entity focusing the mercury issue, the UNEP global mercury

partnership.

1.4. OBJECTIVES OF THE STUDY

Mercury is proven toxic and persistent in the environment. It directly affects human

beings and ecosystem. The control of mercury use and its release needs a clear picture of

mercury route at national and global level. To cure and prevent the mercury toxicity to

environment/humans, there must be a baseline information on the use, reuse and

processing of mercury at national level. Such data would help policy makers prepare

guidelines for stakeholders and to predict any alarming situations on mercury toxicity.

Prior to this study, there was hardly any information on mercury and its products in

Pakistan. The people are unaware of identification of potential mercury sources, the

exposure risk, environmentally safe methods of disposal and reuse of mercury and its

products. The workers of the industries/users are being exposed carelessly to mercury and

mercury products. Assessment and quantification of mercury in Pakistan would play a

critical role in saving human and wildlife from toxic mercury exposure.

12

Different mercury and mercury products are being used in Pakistan. Unfortunately,

there are no or insufficient regulations over the usage and safe disposal of mercury related

products. Mercury using industries in other countries have made some developments in the

reuse of mercury wastes though they are still in the initial stages. The current practices of

the disposal of mercury products within Pakistan have been studied with respect to their

environmental and economic aspects. The following steps have been taken:

Evaluation of current status of mercury and mercury products.

Selection of areas susceptible to mercury contamination.

Collection and analysis of wastewater, solid and hair samples for detection of

mercury.

Preparation of mercury base line data about the current situation.

Assessment of risk to general public based on the collected data.

Establishing a relationship between data collected/generated and point / area source

locations.

Awareness on the health impacts of mercury exposed people.

Developing of mercury waste management plans for priority sectors

This study will help to estimate as to which source is contributing to what extent

towards the mercury releases to the environment. With the help of facts and figures

obtained in this research, the necessary documents are being prepared which will serve as

future guidelines for control of mercury pollution.

This research is aimed to provide baseline study and awareness of environmentally

safe reuse/disposal options of mercury products. The adoptions of these reuse options may

provide the users some financial recovery thus mitigating impacts on the products cost as

well. The communities suffering from unsafe disposal of mercury products will be direct

beneficiaries of the outcome of this research. The overall objectives of this study are given

below;

i. To develop the baseline data of mercury and its products in Pakistan.

ii. To identify the sources of mercury exposure to the different sectors of society.

iii. study the impacts of mercury and mercury products on workers.

iv. quantify the mercury exposure sources.

v. To develop mercury waste management plans to reduce the risk of mercury

exposure.

13

CHAPTER 2

REVIEW OF LITERATURE

Mercury is a naturally occurring element found in air, water and soil, though its

ultimate source is the crust of the Earth. Its distribution in the environment is due to both

natural processes as well as anthropogenic activities. Mercury occurs in various inorganic

and organic forms and is obstinate in the environment. The main three forms of the

mercury include: a) elemental mercury identified by chemical symbol Hg0; b) ionic or

inorganic mercury having chemical symbol Hg (II)or Hg2+

. Hg2+

occurs in nature as Hg (II)

mercuric compounds or complexes in solution; and c) The organic mercury or methyl

mercury with the chemical symbol of Me-Hg. Its occurrence in environment is of

particular concern.

2.1 SOURCES AND RELEASES OF MERCURY

The most significant mercury releases to the environment are through emissions to

air but mercury is also released from industrial, health and other sources directly to water

and land. A fact that is basic to the understanding of mercury’s pathways in society and the

environment is that mercury is an element and, although it may change between different

forms in its cycle, it cannot be broken down or degraded into harmless substances.

Food chains both aquatic and terrestrial, which are harvested from mercury

contaminated areas, bio-accumulate methyl mercury. Although substitutes are available,

mercurial sphygmomanometer and fever thermometers are widely marketed throughout

the world. Cost effective and safe devices are now replacing mercurial devices and

products.

UNEP Mercury Products Partnership, a mechanism for delivery of immediate

actions, has set the goal of reducing demand for mercurial sphygmomanometer and fever

thermometers devices by at least 70 per cent by 2017.

Most of the world’s 600,000 tonnes of mercury reserves are found mainly in China,

Kyrgyzstan, Mexico, Peru, Russia, Slovenia, Spain and Ukraine (USGS, 201283

). Out of

these countries, only one namely Kyrgyzstan is still exporting mercury from primary ore.

14

In 2005, UNEP estimated global annual mercury demand between 3,000 and

3,900 tonnes (UNEP, 200684

). Demand for mercury has fallen significantly over the last 50

years, from 9,000 tonnes a year in the 1960s to 7,000 in the 1980s and 4,000 tonnes a

decade later (UNEP, 200684

). Mercury under the programme of UNEP is being phased out

due to the availability of substitutes and the realization of its toxicity.

Considering the present trends, the overall use of mercury will decline. However,

reduction in mercury use is problematic in the production of Vinyl Chloride Monomer

(VCM), small scale gold mining and in artisanal applications which together account for

45% of global demand.

Anthropogenic mercury emissions into the air accounted for 1960 tons in the year

2010.According to UNEP (201385

), the total emission of mercury on global scale has

remained more or less stable between 1990 and 2010.The geographical distribution has

varied significantly. Due to economic development and population increase, the regions of

Southern and Eastern Asia now account for almost 50% of anthropogenic mercury vapour

emissions into the air. The regions of South America and Sub- Saharan Africa now account

for 30 % of global anthropogenic atmospheric mercury emissions. The mercury emissions

in these regions are still increasing .On the other hand due to concerted efforts, legislation

and control measures, the mercury emissions in North America and Europe have touched a

low level of 8 % (UNEP, 201385

).

Restriction on the use of mercury will, over time result in reduction of mercury

containing devices and products requiring disposal and storage in environmentally

acceptable ways. In 2012, UNEP helped Argentina and Uruguay to develop a regulatory

framework and to find environmentally sound solutions for the storage and disposal of

excess mercury. Both countries developed National Action Plans for the environmentally

sound management of mercury and mercury wastes.

The Global Mercury Assessment: Sources, Emissions, Releases and Environmental

Transport (UNEP, 201385

) states that total global atmospheric emissions of mercury from

human activity in 2010 were estimated to be approximately 1960 (1010 – 4070)

tonnes/year.

Fitzgerald et al., 199886

, Jackson 199787

and Lamborg et al., 200288

tried to

15

estimate and differentiate between natural and anthropogenic mercury emissions in

order to emphasize the significance of human contributions. According to Coolbaugh et al.,

200289

, ―natural mercury sources are responsible for less than 50 percent of the total

mercury releases‖.

According to Lindquist et al., 198490

and Bergan et al., 199991

, ―on the global level

the anthropogenic emissions and deposition rates of mercury are 1.5 to 3 times higher than

those of pre-industrial period. The deposition rates of mercury in environment increased by

2 to 10 fold during the last 200 years in and around industrial areas‖.

According to Mason et al., 199492

, ―the worldwide natural emissions of mercury

are about 1650 metric tons/ year‖. Lamborg et al., 200288

expected 1400 metric tons/ year.

Bergan and Rohde, 200193

expected global natural mercury emissions up to 2400 metric

tons out of which about 1300 metric tons per year comes from land and oceans contribute

up to 1100 metric tons.

According to Lacerda, 199794

, ―the worldwide annual mercury releases into

environment of 460 metric tons from gold extraction in the late 1980’s/early 1990’s which

constituted about 10 percent of the total global anthropogenic releases‖.

According to Pilgrim, 199895

, ―the atmospheric mercury concentrations were

measured at 360 – 4470 ng/m3

over three landfill sites compared to ambient mercury

concentration of 1.5 – 2.0 ng/m3

across Ontario, Canada‖. Mercury also evaporates from

landfill sites. Environment Canada reported mercury concentration in landfill gas of about

10 ng/m3

(Canadian submission, sub 42 gov). Meanwhile, Lindbergh et al., 200196

indicated that mercury emissions from landfills may be higher than earlier assessment.

Maag et al., 199697

reported that around 3.5-4 metric tons of mercury a year was

transported to Denmark during 1992-1993 for recycling. According to Groupe de travail de

1, AGHTM, 199998

, ―2.8 metric tons a year recycled mercury was present in France.

However, major wastes from chlor-alkali production, electrical contacts and laboratories,

among others were not included in the evaluation‖.

According to Pirrone et al., 200199

, ―the amount of mercury in coal varies

considerably depending on the type and the origin of the coal. For example, mercury

contents may vary by an order of magnitude even within the same coal field. Available data

16

indicate that the amount of mercury in coals may vary between 0.01 - 8.0 ppm‖.

According to Bragg et al., 1998100

, ―mercury contents in 7000 samples of US coal at an

average of 0.17 mg/kg where 80% were below 0.25 mg/kg and the main single value was

1.8 mg/kg‖.

According to Pacyna and Pacyna, 2000101

, the removal/retention of vapour mercury

by spray dryers for coal combustors and incinerators is in Scandinavia and the USA. In

general, removal of mercury varied between 35 to 85% in different spray dry systems. The

maximum removal efficiencies were achieved in spray dry systems fitted with downstream

fabric filters‖.

According to US EPA, 1997102

, ―mercury contents in crude oil are nearly between

0.023 - 30 mg/kg. Mercury concentrations in oil depend on the local geology. The use of

certain types of drilling mud is another input of mercury to oil extraction‖. Pirrone et al.,

200199

reported that mercury is present in crude oil on average up to 10 ppb but in some

cases as it may reach high as 30,000 ppb.

Wilhelm and Bigham, 2002103

noted that 0.2 % of crude oil was processed with

high mercury concentration samples from a small field in California, USA. Shah et al.,

1970104

, Filby and Shah, 1975105

and Bloom, 2000106

excluded the samples from this field.

The mean value decreased up to 1000 times for three datasets with unusual high mean

values.

According to COWI, 2002107

and US EPA, 1997102

, ―the mercury contents in

natural gas depend on the geology of the hydrocarbon fields. Mercury emissions may occur

during extraction, refining, gas cleaning steps and use‖.

According to Pirrone et al., 200199

, ―the mercury contents in pipeline quality gas

are mostly below 10 μg/m3 level in Europe. However, the unrefined natural gas is likely to

have higher mercury contents‖.

COWI, 2002107

determined that a mercury emission in environment is dependent

on the level of mercury in fuel and amount of fuel burnt. Friedli, H.R. et al., 2001108

found

that the tree and mainly their needles and leaves absorb the atmospheric mercury and this

mercury is again released when wood and other biomass is burnt in the atmosphere.

17

According to US EPA, 1997102

and NJ MTF, 2002109

, ―the average content of

mercury from wood burned is about 0.002 ppm in the USA. All of the mercury emitted

from the wood burned is released into the air‖.

US EPA, 1997102

recommended an average atmospheric emission factor of 0.0026

g mercury per metric ton of wood burned .The same factor is in USA for wood combusted

in boilers.

In USA, Friedli et al., 2001108

found the mercury contents in garbage and

vegetation from seven different locations ranged between 0.01 – 0.07 mg Hg/kg dry

weight.

In Denmark Skårup et al., 2003110

estimated mercury content of burned straw and

wood between 0.007 - 0.03 mg/kg dry weight.

According to Kindbom and Munthe, 1998111

, ―in Sweden mercury content in fuel

wood on dry basis was between 0.01 - 0.02 mg/kg dry weight and 0.03 - 0.07 mg/kg dry

weight in willow wood. In bark, mercury content was 0.04 mg/kg dry weight whereas the

mercury content was 0.3 - 0.5 mg/kg dry weight in fir needles‖.

Feng et al., 2004112

reported that broad local ambient mercury pollution from zinc

production with original technology took place in the Hezhang area in the Guizhou

province in China. They calculated mercury contents in ores and coals used and in smelting

residues and coal ashes. Nriagu and Pacyna, 1988113

reported 25 g Hg/metric ton of zinc

production. They further verified that mercury produced in zinc smelting residues is

readily leachable by water.

According to US EPA, 1997102

, ―the releases of mercury occur mainly during the

drying/roasting of the feed stock and during the smelting. Converters and refining furnaces

may also emit mercury residues from the material during the copper extraction process‖.

The levels of mercury in the ores vary and can be high compared to other natural

raw materials in some cases (COWI, 2002107

).

According to Maag, 2004114

, ―gold extraction processes from the placers and other

ores is an important source of mercury emissions. Gold extraction from ores is one of the

main sources of mercury releases among metal extraction activities in the Arctic countries.

Mercury releases to both land and the atmosphere from this activity may be significant‖.

18

According to US EPA, 2003a115

, ―5474 kg of mercury were emitted to air, 0.4

kg to water, 1,886 kg to site land while 594 kg were released off-site from a total of 25 gold

mines in the western USA‖. Jasinski, 1994116

reported that 114 metric tons of mercury was

produced from gold mining operations in 1990 as byproduct. One silver mine in Nevada

remained source of 6.4 kg of mercury in air and 15911 kg in land during the year 2001(US

EPA 2003 a115

).

According to Lassen et al., 2004117

, ―the main sources of iron ores contain

0.02-0.085 mg/kg Hg in the Russian Federation while the release of mercury is 0.06 mg/kg

during pig iron manufacturing in the Russian Federation‖.

According to Berndt, 2003118

, ―the amount of mercury lies between 0.001 to 0.016

mg/kg in the ore concentrate and varied from 0.001 to 0.040 mg/kg in the tailings‖.

Pacyna and Pacyna, 2000101

estimated the release factor 0.04g per metric ton

production of pig iron in Russian Federation, inclusive of all raw materials used. About

99% of the mercury from this source was released in to the air.

According to Cembureau, 1999119

, ―a small proportion of mercury is retained by

the clinkers. The balance escapes the kiln along with dust and exhaust gas. Mercury

condenses between 120-150° C on particles in the kiln system‖. Kiln emissions may be

reduced by fabric filters (FFs) and ESPs. However, the efficiency of these devices in the

removal of mercury is not clear (Pirrone et al., 200199

).

The average content of mercury in 418 samples was 0.07 mg/kg reported from

Germany in 1991. The mercury concentration was between <0.02 mg/kg (detection limit)

to 0.3 mg/kg (VDZ, 2000120

). According to Skårup et al., 2003110

, ―the average content of

mercury in cement in Denmark in 2001 was between 0.02 to 0.05 mg/kg‖.

It is estimated that total annual mercury emissions were 1.6 metric tons from Kraft

and soda recovery furnaces and lime kilns of 153 units in USA in 1994(US EPA, 1997a121

).

The main source of emissions of mercury is the recovery furnace.

From chlor-alkali plants in France out of total Hg released, 3 to 14% is emitted to

air, 16 to 90% is discharged along solid wastes or semi-solid wastes like sludge. A total of

10 to 70% of the losses are internal while less than 2% mercury is released through water

discharge, land, and products from chlor-alkali plants (OSPAR, 2002122

).

19

According to Lassen et al., 2004117

, ―amounts of mercury in the soil were large at

the mercury cell facilities (which have been shut down) in Russia in the 1980's and 1990's.

The sources of this mercury were handling losses, leaks and on site storage of mercury

waste‖.

Chlor-alkali plant sites were studied by Southworth et al., 2004123

and Kinsey et al.,

2004124

.According to these investigators these plants pose significant challenges during

the cleanup process. This process may result in mercury contamination of groundwater,

surface water, soils, sediments and debris.

According to Qi et al., 2000125

, ―mercury releases, including mercury in wastes,

from chlor-alkali manufacturing units of China were from 500-1400 g of mercury/ton of

sodium hydroxide production before 1977 but dropped to 160-180 g of mercury/ton of

sodium hydroxide (caustic soda) production in 1997. However, these decreased values

were still higher than some other countries‖.

According to US EPA, 1997102

, ―phenyl mercuric compounds have been used in

the past as a catalyst to manufacture poly urethane. This process lead to mercury releases.

At present, phenyl mercuric compounds are no longer produced in the United States‖.

Mercury releases occur during filling of the metal in thermometers. Sealed mercury

thermometers pose no health risks (US EPA, 1997a121

). However, breakage of the

thermometers may lead to mercury ambient air levels that may pose risk to small children

(Carpi and Chen, 2001126

).

The mercury containing thermometers may be recycled and the mercury

recovered. In other cases mercury may be collected separately and recycled (Barr,

2001127

).

The estimates released by the Unilever (2003128

) show that not more than 10

kg/metric ton mercury was released from their thermometer factory in India.

Based on a telephone survey in 1990, the breakage rate of thermometers was

estimated 5% (US EPA, 1992129

).According to Barr, (2001127

), ―limited data show this rate

20

to be as high as 50% in the USA. Out of these broken thermometers, 10% mercury is

released into the air while 20% mercury is washed and released to waste water. The

balance 70% mercury is divided amongst municipal solid waste, infectious waste and is

recycled‖.

According to Skårup et al., 2003110

, ―in Denmark about 1/3 of mercury from broken

domestic medical thermometers ends up in waste water due to clean up of the spills and the

balance is dispersed between municipal solid waste and hazardous waste. It is estimated

that 90% of mercury in thermometers used by industry/laboratories is disposed of with

hazardous waste for recycling whereas 5% is disposed of with municipal waste and waste

water respectively. In Denmark, mercury from thermometers used in the hospital sector is

reported generally to be disposed of as chemical waste‖.

The reported lifetime of fluorescent light sources ranges from 8-10 years under

Danish conditions (Skårup et al., 2003108

).

According to Hansen and Hansen, 2003130

, ―20-30% consumed button cells and

30-60% large alkali batteries were collected separately in Denmark in 2001‖.

Barr, 2001131

estimated that form the mercury used in paints approximately 5 % is

discharged with wastewater, whereas 3% goes with municipal solid waste and remaining

92% is emitted to the atmosphere.

According to Maag et al., 1996132

and Skårup et al., 2003110

, ―mercury amalgam

filled teeth after removal are disposed as general waste or separately collected as hazardous

waste and may be sent for recycling. In Denmark as in other countries of European Union,

a large number of extracted teeth are sent to dental schools for use in practical dentist

teaching‖.

Mercury constantly loses in very minimal amount during teeth fillings. Such

mercury productions have been considered slightly paltry by some workers. Skare and

Engquist, 1994133

estimated mercury discharge from tooth filling amalgam based on

excretion rates which were 60 μg/ (day*person) with feces and urine. However, this

21

estimate lack the food intake contribution (Sörme and Lagerkvist, 2002134

; Sörme et al.,

2003135

).

According to Lassen et al., 2004117

, ―laboratories are required to defuse the

mercury containing wastes in the Russian Federation. Overall, the waste is transported to

landfills but small laboratories may defuse the reagent wastes before discharging to the

sewerage system‖.

Reportedly mercury concentrations in medical waste was 50 times more compared

to the general municipal waste, whereas general medical incinerators accounts for 60 times

more mercury as compare to the pathological waste incinerators (US EPA, 2004136

).

In 1995, 28% of the total waste incinerator emissions were recorded in Canada

from 218 biomedical plants. This contributed approximately 580 kg of mercury in the air

(Environment Canada, 2000137

). Similarly, from USA, atmospheric mercury emissions

was recorded upto14.6 metric tons through pathological waste incineration weighing up to

204,000 metric tons and general medical waste of total 1,410,000 metric tons in 1996 (US

EPA, 1997102

). This accounts to an average atmospheric emission to the tune of 8.9

g/metric ton of waste.

According to US EPA, 2004136

, ―average for the general medical waste was

calculated in 2004 to be a little higher i.e. 8.2 g mercury per metric ton of medical waste‖.

In Denmark, dry sludge in 1999 was contaminated with 1.2 g Hg/metric ton of

sludge. Approximately 41% of this sludge was applied to forest or used for agricultural

purposes while 28% was incinerated and the balance was stored, treated or land filled

(Skårup et al., 2003110

, based on Danish EPA, 2001).

In big cities like Moscow and St. Petersburg, the content of mercury in sludge on

dry basis is from 1 to 2 g Hg/metric ton. In smaller cities of Russian Federation, the

mercury content in sludge on dry basis varies from 0.1 to 1 g Hg/metric ton (Lassen et al.,

2004117

).

22

According to Lindberg et al., 2001138

, ―both dimethyl and monomethyl mercury

are produced in landfills‖. Methyl mercury is produced from elemental mercury due to

anthropogenic as well as natural biological processes (UNEP, 20021).

Mercury released to the atmosphere from waste is higher during day time compared

to night (Shunlin Tang et al., 2004139

).

According to Lindberg, 2004140

, ―the mercury fluxes from landfills face operations

are significant but generally below 10% of the total release of mercury from landfills. In

the state of Florida, USA, estimated 10 to 50 kg mercury is released to the air per year from

landfills‖.

Most of the mercury from crematoria is emitted into atmosphere (NJ MTF, 2002109

)

while a small amount is retained by bricks and ash (Reindl, 2003141

). According to

Hylander and Meili, 2005142

, ―mercury releases to the atmosphere from crematoria of 0.28

metric tons per year in Sweden‖.

According to Axenfeld et al., 1991143

, Pirrone et al., 200199

, ―in Europe

approximately 60 percent of the anthropogenic releases were in gaseous elemental form,

30 percent as gaseous divalent mercury and only 10 percent as elemental mercury on

particles‖.

According to Mason and Fitzgerald, 1996144

, 1997145

, ―the mercury cycle in oceans

and other water bodies. Elemental mercury, dimethyl mercury and to some extent, methyl

mercury are common components of the dissolved mercury pool in deep ocean waters‖.

Mercury supplied by OECD countries is being widely used in limited gold mining

operations in the Amazon Basin as well as other parts of the World (Maxson and

Vonkeman, 1996146

) as quoted by (Scoullos et al., 2000147

) .This is happening

notwithstanding the fact that deal and usage of mercury is banned in Brazil (Maxson and

Vonkeman, 1996146

) as cited by (Scoullos et al., 2000147

). Another specific case include the

export of a complete old chlor-alkali production plant containing mercury from Denmark

to Pakistan. However the involvement of the Danish Minister of the Environment

23

restricted the factory from being assembled in Pakistan and the facilities were returned

for disposal.

Mercury was being smuggled into Brazil from Colombia and Venezuela (Maxson

and Vonkeman, 1996146

) as cited by (Scoullos et al., 2000147

).Since the price of mercury is

low, therefore there is no incentive to use mercury saving technologies in small scale

artisanal gold mining.

According to Lindley, 1997148

, ―conversion costs of a standard West European

chlor-alkali plant is about $US 500 per metric ton of chlorine capacity‖. According to

Harris, 2001149

―estimated conversion costs of chlor-alkali plants is between $US 400 to

700 per metric ton of chlorine capacity. However, there are operating cost savings between

$30 to 50 per metric ton of chlorine capacity‖.

2.2 USES OF MERCURY AND MERCURY COMPOUNDS

Mercury is being used in many products and processes all over the world including

in small-scale gold mining; manometers and thermometers; electrical switches; fluorescent

lamps; dental amalgams, batteries and VCM (vinyl-chloride-monomer) production and

some pharmaceuticals.

Artisanal Small Scale Gold (ASGM) mining sector is one of the largest user of

mercury which is used to separate gold from the ore. Ten to fifteen million gold miners

mainly in Africa, Asia and South America are exposed to mercury vapors. An estimated

three million of them are women and children (UNEP, 2012150

). Mercury use in ASGM

was estimated by Mercury Watch at 1,400 tonnes in 2011, and rising gold prices were

likely to increase that use (UNEP, 2012150

). The practice threatens the health of the

workers and their families as well as downstream people who consume

mercury-contaminated fish or drink the water. This type of gold extraction, using mercury

should be replaced by low mercury or mercury free methods but socio-economic

conditions often retard the adoption of better practices (UNEP, 2012150

). The Global

Mercury Partnership promotes the establishment of national action plans and reduction

targets, encourages collaboration and the sharing of best practices to reduce mercury use,

and helps take-up innovative market-based approaches.

24

Second largest user of mercury is the VCM industry. Polyvinyl chloride (PVC) is

used as catalyst in the production of plastics. China is the major consumer of VCM and

used about 800 metric tons in 2012. In China, the mercury catalyst is recycled by

enterprises that hold permits for hazardous waste management. The amounts that may be

emitted or released are not known (UNEP, 2013151

).

Once a globally-binding treaty is in place, there is hope that global mercury

demand will decline sharply since industries that use mercury in products and processes or

release it to the environment will be required to meet the obligations set out in the

instrument.

Despite serious efforts to phase out, mercury is still being used in devices and

articles of common use. Similarly, thermostats, relays, fluorescent light, batteries,

cosmetics, specially skin lightening creams, dental fillings and host of other articles

contains mercury.

Mercury is widely used in compact fluorescent lamps (CFLs). The demand for

these lamps is increasing in the quest for energy efficiency. According to the EU Directive

2002/95/EC, mercury content in CFLs not exceeding 5 mg per lamp is allowed. These

lamps reduce electricity consumption and help reduce mercury emissions by 10% in

countries that generate electricity largely from coal (EU, 2010152

). It may be mentioned

here that coal combustion releases mercury into atmosphere.

Intentional uses of mercury take place in many products in the Europe. The three

main intentional uses of mercury products accounts for 18 percent of the total mercury

emissions to air in European region in mid-1990’s (Munthe and Kindbom, 1997153

).

According to Lawrence, 2000154

, ―the amount of mercury byproducts used on

worldwide basis might be 400 metric tons. Most countries do not reveal their mercury

production, due to which there is a high degree of uncertainty on the current world

production‖.

Worldwide 1344 metric tons of mercury was employed in chlor-alkali industry in

1996 (UNEP, 20021).

25

Rendering to Skårup et al., 2003110

, ―mercury is used in ABS systems of 4-wheel

drive vehicles. However in US, the new cars do not have mercury in ABS systems‖.

Forty-nine metric tons or 13% of the total intentional use of mercury is US was in

the production electronics including switches and wiring devices (Sznopek and Goonan,

2000155

). According to Barr, 2004156

, ―the annual use of mercury in switch/relay products

which include thermostats represented 42% of product use in the US, i.e. a total of 103

short tons‖.

The linear fluorescent light tubes with mercury constitute 95 % while the remaining

5 % are either, neon lamps, mercury vapour, compact tubes or metal halide and

high-pressure sodium (NESCAUM, 1998157

,NJ MTF, 2002109

). The amount of mercury

used per lamp has now been reduced by a factor 10.But these lamps are more expensive.

Alternative lamps without mercury are under development (COWI, 2002107

).

The reduction in mercury content of 4 feet lamp is 48 mg in 1985 and in 1999 it is12

mg in USA (NJ MTF, 2002109

).

According to UNEP, 20021, ―a number of mercury compounds have been used in

biocides, paints, paper industry, paints and for preserving seed grains and other agricultural

applications. These uses have been discontinued or banned in many countries. The use of

mercury for seed dressing is common. Use of such wheat seed was the cause of mercury

poisoning in Iraq some decades ago‖.

According to Lassen et al., 2004117

, ―Russian Federation had used 14 compounds of

organomercuric pesticides. The production of such compounds has been discontinued but

such compounds have been used from stocks to the tune of 20-40 tons‖.

To control pine apple disease in Australia around 120g/L of mercury is used in

fungicide as methoxy-ethyl mercuric chloride in sugarcane earth (UNEP, 20021).

According to Wankhade, 2003158

, ―eighty five metric tons of organic mercurial

pesticides were used in India in 1999-2000 from stockpiles. These pesticides are now

banned in India‖.

26

In USA, the use of mercury biocides in latex paint was banned in 1991. Air is the

main receiving medium for mercury vapor from latex paints (US EPA 1992129

, Agos et al,

1990159

, NJ MTF 2002109

).

According to Husar and Husar 2001160

, ―mercury used in interior latex paint

amounted roughly to 45 ppm while in exterior latex paint it amounted to 1050 ppm‖.

The recommended rate of mercury in paint is 460 mg Hg/L in Australia (Alphen,

1998161

). Alphen further identified mercury level 300ppm in some of the paints through

limited survey of South Australian paints. In Costa Rica, the limit for mercury and lead in

paints is maximum 50 ppm (US EPA, 2002162

).

Mercury compounds find application as a preservative in a number of

pharmaceutical preparations like eye drops, vaccines and of some herbal medicines

(COWI, 2002107

). For instance, thimerosal/thiomersal (ethyl thiosalicylate) is known to

prevent pathogen growth in vaccines for decades. But such uses have decreased recently

(UNEP, 20021). Mercury emissions from such compounds may occur through

manufacture, usage and disposal of these products (UNEP, 20021 and COWI, 2002

107).

Mercury compounds are still in practice as preservative in some vaccines in

Denmark. The influenza vaccines contain only 50 μg thimerosal per dose .With this

minimal amount per dose, the use of thimerosal (mercury compound), and total influenza

vaccine utilization is less than 20g/ year in Denmark having population of 5 million.

According to UNEP, 20021 and COWI, 2002

107, ―mercury compounds are widely

used in skin lightening creams and soaps. Some eye cosmetics also contain mercury

compounds. The production and use of mercury compounds as cosmetic preventatives or

in skin lightening creams have decreased radically in the developed world. However, the

case of developing world is different. Production and disposal of such compounds release

mercury‖.

Skin whitening soaps contain approximately 3% of mercury iodide (HgI2) while in

creams the concentration of ammoniated mercury may reach upto 10% (OECD, 1994163

).

27

According to Mahe et al., 1993164

, ―the skin lightening cosmetics are widely used

in African countries. 25% of 210 surveyed women in Bamako, Mali reported using skin

bleaching cosmetics). Out of these, 11% used mercury containing compounds whereas

16% used agents of unknown composition‖.

According to Adebajo, 2002165

, ―77% of 440 interviewed male and female traders

used skin lightening cosmetics. Hydroquinolone based products were commonly used

products while cortico steroids and mercury based products were also widely used in

Lagos, Nigeria‖.

Mercury compounds were the active ingredients in 31% cosmetics used amongst

536 women in Lome, Togo. Fourteen brands of toilet soap from Kisumu, Kenya were

analysed by Harada et al., 2001166

. They found that European made soaps contained

0.47-1.7 % of mercury iodide while in the local brands only traces of mercury were

observed. According to Glahder et al., 1999167

, the three brands of soap analysed from

Tanzania contain mercury. The soaps could have proportion of 2% mercury iodide. The

observed mercury content was 0.69%.

Mercury bearing skin lightening soaps were banned in European Union in the year

2000(Danish EPA, 2000168

). The Danish EPA analysed 7 types of mercury containing

soaps from the markets in Denmark which contained 1-3 % mercury iodide.

According to Maxson, 2004169

, ―Ireland imported 17 metric tons of mercury in

1999 for use in skin lightening soaps which were exported out to Europe‖. Under Annex 5

of European Union regulations implementing Rotterdam Convention the production of

cosmetics containing mercury was banned in 2003.

In the USA, use of mercury as laboratory chemical decreased from 32 metric tons

in 1990 to 20 metric tons in 1996 (Sznopek and Goonan, 200029

). Approximately one third

of the total mercury was utilized in laboratory instruments. In Denmark the use of mercury

in laboratory chemicals has declined from 510 kg per year in 1982-1983 (Hansen, 1985170

)

to 20-40 kg per year in 200 (Skårup et al., 2003110

).According to AGHTM, 2000171

, ―the

decrease in mercury use in laboratories is due to its replacing in Kjeldahl and Chemical

28

Oxygen Demand (COD) methods. About 900 g mercury was used as mercury sulphate

for COD analysis‖.

In New Jersey, USA, dental filling resulted in Emission of mercury. Reportedly,

each corpse contains average 2.9 g/ corpse mercury where the concentrations may vary

from 0.8 and 5.6 grams (NJ MTF, 2002109

). This mercury comes from dental fillings in

New Jersey, USA. According to Reindl, 2003172

, ―the balance in each corpse comes from

body tissues like blood, hair, etc. which is due to largely fish consumption and other

exposures in the range of 1 x 10-5

- 0.1 g mercury‖.

2.3 MERCURY EXPOSURE

Although it was not clear in start but prolonged exposure if mercury resulted in

medical conditions in human beings and animals so much that it was noticeable by the

1970s. The mercury exposure can lead to various toxic effects in human beings like CNS

damage, renal complication etc. In animals the exposure resulted in growth rate,

reproduction rate etc.

Mercury once released from anthropogenic or natural sources because of its

propensity to travel through air and water can impact soil, sediments and organisms over

large areas.

Mercury bio-accumulates up the food chains. Mercury through metabolism of

microbes/phytoplanktons in aquatic environment changes to highly toxic methyl mercury.

Methyl mercury accounts for 90% of the mercury in fish. In aquatic ecosystem, it reaches

the highest level in predator fish such as swordfish and shark that may be consumed by

humans. It is known to effect reproductive systems of birds and predatory mammals

According to Dufault et al., 2009173

, the Institute for Agriculture and Trade Policy

in USA recently found that high fructose corn syrup (used in sodas, ketchup and bread)

could also contain elevated mercury levels. Zhang et al., (2010174

) suggested that in areas

of intensive mercury mining and smelting as well as areas with big coal fired power plants,

rice crops could be contaminated.

Mercury can seriously harm human health, and is a particular threat to the

development of fetuses and young children. It affects humans in several ways. As vapour it

29

is rapidly absorbed into the blood stream when inhaled. It damages the central nervous

system, thyroid, kidneys, lungs, immune system, eyes, gums and skin.

Neurological and behavioral disorders may be signs of mercury contamination,

with symptoms including tremors, insomnia, memory loss, neuromuscular effects,

headaches, and cognitive and motor dysfunction. According to Smith et al., 1970175

, ―the

workers exposed to elemental mercury vapour showing a clear increase in symptoms of

dysfunction of the central nervous system levels at concentration greater than 0.1 mg/ m3‖.

According to Bidstrup et al., 1951176

, obvious mercury poisoning symptoms in urine

appear at concentrations higher than 300 g in a 24 hr sample. Langwarth et al., 1992

177conducted that ―several studies showing evidence of neurotoxicity at approximately 2 –

4 fold lower concentration. Self-reported memory disturbance, sleep disorder, anger,

fatigue and /or hand tremors were increased in workers chronically exposed to an estimated

air concentration of 0.025 mg/ m3

".

Mercury effects central nervous system, eye sight, cardiovascular system and

causes tremors (McKelvey and Oken, 2012178

). Heart function normalities were reported

by Jalili and Abbasi, 1961179

in patients in Iraq who consumed ethyl mercury coated grains

and were hospitalized for severe poisoning. In 1995, Salonen et al.,180

studied 1,833 fishing

men focusing their dietary constituent primarily fish in relation to the concentration of

mercury in hairs and urine in relation to Acute Myocardial Infarction (AMI) and death

from coronary heart disease or cardiovascular disease. Concentrations of mercury in the

studied group ranged from 1.1 to 95.3 g per day (average 7.6g/day). Reported from

seven years study men in the highest tertile with hair mercury content 2µg/g had a twofold

higher risk (1.2 – 3.1) of AMI than men in the two lowest tertiles. According to Rissanen et

al., 2000181

, ―a protective effect of omega 3 fatty acids shows with respect to acute

coronary disease. However, it was found that the less evident in those high mercury content

in fish could reduce the protective effect of Omega-3 in individuals having >2g/g Hg in

hair‖.

According to Boucher et al., 2012182

, the Inuit population of Quebec has among the

highest levels of exposure to mercury of any population in the world. It was recently

concluded that children with higher levels of contamination are more likely to be

30

diagnosed with attention deficit hyperactivity disorder. In young generations, it can

affects neurological damage resulting in symptoms such as mental retardation, seizures,

vision and hearing loss, delayed development, language disorders and memory loss.

The study of people exposed to high level of mercury vapour or those constantly

exposed to high levels showed negative impacts on personality, motor functions, sensory

and cognitive abilities (US EPA, 1997102

, Aronow et al., 1990183

).

The ―elemental mercury can oxidize in body tissues to divalent mercury. Kidneys

concentrate this mercury more than other organs. The concentration of this divalent

mercury in occupationally unexposed groups varies normally from 0.1 – 0.3 µg/g‖ (

Drasch et al., 1996184

; Barregard et al., 1999185

; Hac et al., 2000186

; Falnoga et al., 2000187)

According to Kazantzis et al., 1962188

; Borjesson et al., 1995189

and Barregard et

al., 1999185

, ―mercury concentration in kidney of a person with occupational exposure may

be as high as 35 µg/g‖.

High mercury concentrations in hair are also known for abnormal visual fields

(Lebel et al., 1998190

). The dosage linked decline in visual and motor functions are known

to be effected by with hair mercury concentrations. Mercury intoxication is not clinically

significant below 50 g/g (Lebel et al., 1998190

).

According to Tamashiro et al., 1986191

, ―evaluated causes of death among residents

of a small area of Minamata City are due to the highest occurrence of Minamata disease

and used age specific rates for the entire city as a standard. Between 1970 and 1981, the

number of deaths in women resided in Minamata area due to nephritic diseases was higher

than expected‖.

According to US ATSDR, 1999192

; Pelclova et al., 2002193

, ―the exposure to

inorganic, elemental, and organic mercury can occur due to the use of skin lightening

creams containing mercury, mercury containing traditional medicines, ritualistic uses of

mercury and certain pharmaceuticals. Ethyl mercury thiosalicylate commonly called

thiomersal is used as a preservative medicine for some types of vaccines and

31

immunoglobulins‖. According to Ernst and Coon 2001194

; Koh and Woo, 2000195

and

Garvey et al., 2001196

, ―significant exposures may occur by the use of mercury containing

traditional Chinese or Asian medicines‖.

According to Feng et al., 1998197

, ―total mercury and methyl mercury

concentrations in scalp hair of 243 male persons in three areas of the Tokushima

Prefecture, Japan as well as in 64 males of the Chinese city of Harbin and 55 males in the

Indonesian city of Medan. All subjects were randomly chosen males aged 40-49 years.

They found the highest concentrations in subjects living in a seaside area reported to be

without local direct anthropogenic contamination. Total mercury concentrations here

ranged from 1.7-24 g/g hair (mean 6.2 g/g, 78 subjects) thus close to and exceeding the

adverse effect benchmark level of about 10 g/g maternal hair derived from the Faroe

Islands studies. The mean concentration for all three investigated areas in Japan was only

slightly lower i.e 4.6 g/g hair (243 subjects)‖.

According to Feng et al., 1998197

quoted Suzuki (1991198

), ―mercury hair

concentration levels found in residents of three villages in Papua New Guinea which were

not influenced by local direct anthropogenic contamination. The highest concentrations

were found in the seaside village Dorogi with means 4.1 and 4.4 µg/g hair for males and

females respectively. However, concentrations were slightly lower in a riverside village

6 kilometers from the coast and lowest in a village 25 kilometers from the coast‖.

According to Akagi and Naganuma, 2000199

, ―separate measurements for methyl

mercury and total mercury to distinguish between exposures through an aquatic diet and

direct exposures of elemental mercury from gold extraction activities. They found methyl

mercury concentrations exceeding the adverse effects level for adults i.e. 50 g/g in hair.

They surveyed 3.2 percent of the 559 inhabitants with the highest individual level being

132 g/g. These values are considerably higher than the adverse effect benchmark level of

10 g/g maternal hair derived from the Faroe Islands studies‖.

According to Vasconcellos et al., 1998200

, ―total mercury concentrations in scalp

hair in 13 out of 17 tribes of Indians inhabiting the Xingu Park in the Brazilian Amazon.

Methyl mercury concentrations in hair were also measured in six investigated groups.

Geometrical means for total mercury concentrations varied among the tribes in the range of

32

3.2-21 g/g hair but most group means were between 10 and 20 g/g. In the tribes,

methyl mercury was also measured and found in the hair samples. In the same study, three

groups of inhabitants were also investigated in the Brazilian State of Amapá‖.

According to Franchi et al., 1994201

, ―there was found a correlation between the

prevalence of micronuclei in peripheral lymphocytes and blood mercury concentrations in

fishermen who had been eating mercury contaminated seafood‖.

Usually the concentrations of mercury are below the detection level in many food

stuff less than 20 ng Hg/g fresh weight (US EPA, 1997102

). The main source of methyl

mercury is fish and marine mammals. The highest concentrations of mercury are found in

king mackeral, shark, pike, walleye, swordfish, marlin, barracuda, scabbard toothed

whales and seals.

Von Rein and Hylander, 2000202

reported that an important constituent of diet in

Sweden due to long coastline, many lakes and rivers. According to Louekari et al., 1994203

,

―the accumulation of mercury in fish present during several decades in Finland. In the late

1960's about 10-15 percent of the lakes and coastal waters were affected by high mercury

concentrations generally caused by direct aqueous releases from pulp and paper industry

and related mercury based chlor-alkali production in Finland. Average concentrations of

mercury in northern pike measured 1.52 mg/kg wet weight in these freshwaters and

brackish coastal waters at that time‖.

On the other hand, Hg0 vapors are rapidly absorbed by lungs to the extent of 80%

and distributed in the body and cross placental and blood brain barriers (ATSDR, 19995).

Mercury levels in urine of miners who frequently burn gold mercury amalgams in

open pans were detected 20 µg/L in urine. Similarly in gold shop workers in Amazonian

village the mercury concentrations in urine was reported 1,168 µg/L. Higher concentration

of mercury was observed in the worker who worked in confined environment.

33

CHAPTER 3

MATERIALS AND METHODS

This study focuses on identification and quantification of mercury releases in

Pakistan. The mercury is released into the environment through the use of mercury and

mercury containing products as well as through use of certain high volume materials with

mercury trace concentrations. The calculation of mercury releases into our environment

has been made on the basis of guidelines, methods, sources and factors contained in the

United Nations Environment Programme (UNEP)’s Toolkit for identification and

quantification of mercury releases (UNEP, 2005204

)

The Toolkit comprised of a standardized procedure to develop reliable and

comparable source inventories which are given below;

1. Apply screening matrix for identification of main source categories present in the

Pakistan and classify this main source categories into further sub-categories and

gather supplementary qualitative evidence to identify existing activities and

sources of mercury releases in the country; and if feasible, the relative importance

of each

2. Collect detailed quantitative information on the identified sources, and quantify

releases with source specific data or default mercury input and output distribution

factors from the Toolkit

3. Apply nationwide to establish full inventory and report results using guidance

given in the standard format.

3.1. IDENTIFICATION AND QUANTIFICATION

METHODOLOGY

A pragmatic and viable methodology was formulated to identify and quantify

mercury emission sources in Pakistan to make an assessment of total volume of mercury

available in the country. This exercise included the following steps;

34

1. Identification of mercury and mercury products usages and emissions by

federal and provincial Environment Protection Agencies.

2. Selection of the areas prone to mercury contamination in the Pakistan.

3. Collection of wastewater and solid waste samples from the country.

4. Collection of human hair samples from chlor-alkali, dental and control group

sectors

5. Analysis of the samples in the laboratories of the Institute of Chemistry,

University of the Punjab, Lahore and University of Aberdeen, Scotland, UK.

6. Collection of data related to mercury and mercury products from markets/

industries of Pakistan.

7. Preparation of baseline data of mercury and mercury products related to the

current mercury situations in Pakistan.

To accomplish the objectives of mercury data, UNEP’s Toolkit (UNEP, 2005204

)

was used for preparing the inventory throughout the country. Mercury issue is a new

subject for Pakistan. Before this study, nobody had any experience in preparing an

inventory of mercury releases in the country. The field exercise revealed that the

knowledge on the inventory process and concepts and techniques regarding data gathering

and analysis is very limited in the country.

Emission factor is a parameter that essentially plays role in the scheming emission

of mercury into the environment. If emission factors are not assigned values, it is

complicated to effectively calculate the mercury releases. In this regard, the UNEP’s

Toolkit clearly identifies emission factor values according to specific source

categories/sub-categories. Although the UNEP’s Toolkit is a very useful document for the

development of a mercury release inventory report, even though it mostly seems to be

designed for use in developed countries rather than developing countries. This may create

some confusion for developing countries with limited experience (UNEP, 2005204

).

Determining release sources for Pakistan mainly depended on the UNEP’s Toolkit.

However, in a few cases, it poses some difficulty and complexity. Based on available

knowledge and information, the following sources were focused;

35

1. Chlor-alkali plants.

2. Health sector (hospitals, health care units, and clinics) for both mercury contained

in products (thermometers and amalgam fillings) and mercury released from waste

incineration.

3. Landfill (municipal waste dumping).

Besides undertaking field survey for primary data acquisition, the desk study was also

carried out on other sources of possible mercury releases including;

4. Production of secondary ferrous and non-ferrous.

5. Energy sources.

6. Waste burning (industrial and medical waste).

7. Production of lime, etc.

3.1.1. Identification of mercury releases

In order to identify mercury releases, a team was set up for the identification of

mercury releases in the country. The sampling points were also identified by the team .The

team comprised of representatives of provincial Environmental Protection Agencies. The

author coordinated and visited all four provinces regarding the collection of 181 solid,

waste water and hair samples for the analysis of mercury. The identification codes were

allotted for the samples by using fixed marker on paper tape. All the samples were

immediately labeled in the field .The detailed labeling was performed in the laboratory.

3.1.2. Quantification of mercury releases

In order to quantify mercury use and releases data, a country wide team was set up

for the quantification of mercury and mercury compounds, its uses, releases and import.

The team comprised of representatives of federal and provincial Environmental Protection

Agencies, Customs Department and Institute of Chemistry, Punjab University, Lahore.

The author coordinated and visited all four provinces regarding the collection of data from

markets about the mercury and its compounds.

The data was collected from Custom Department, relevant line ministries

especially Ministry of Industries and Production, Ministry of Petroleum and Natural

Resources, Ministry of Science and Technology, Ministry of Health, Federal and

36

Provincial Environment Protection Agencies and different chemical stores.

From January 2008 to September 2008, the data was collected from all major

industrial areas of the country. The data was stored in the Ministry. Approximately 90 %

responses were received from all the sectors as described in the Toolkit (UNEP,

2005204

).Sector wise data was mentioned in the results. The collected data was fed in

UNEP’s Toolkit for the quantification of mercury releases in the country.

3.2. COLLECTION OF SAMPLES

The data gathered by the quantification team was analyzed to figure out the

mercury usage and release hotspots. After the quantification of mercury releases in the

country, the team members with the help of UNEP’s Chemicals Expert prioritized the

samples from all the four provinces of the country. The samples were based on mercury

releases as well as on hotspots like chlor-alkali industries. Hotspots represent 57 % of the

mercury releases in the country. All the 181 identified and prioritized samples of soil,

water and hair were collected from four provinces by the author with the help of provincial

Environmental Protection Agencies.

3.2.1. Waste water and soil samples

The wastewater and soil samples were obtained from selected mercury affected

sites in all the four provinces of Pakistan to assess the mercury pollution level and water

contamination. For this purpose, 109 samples were collected and analyzed for mercury at

the laboratories of the Institute of Chemistry, University of the Punjab, Lahore, Pakistan.

Cold Vapour Atomic Absorption Spectrometry method was used for mercury analysis.

3.2.2. Hair samples

The study was designed to collect hair samples from the workers of hotspots as well

as prioritized sectors like chlor-alkali industries (One industry which is using mercury cell

technology and other industry which has phased our mercury cell technology), health

sector (dental amalgam) and control group. The people were selected of different age

groups with different working experience. The workplace was the only discriminator for

the exposure of mercury. Since, the workers were usually locals of the neighboring areas,

and the food they consumed was mostly imported from other regions of the country

(having no or little industrial exposure). Hence, the chances of Hg contamination through

37

food were almost negligible.

It is recognized that the mercury in human hair is mainly methyl mercury (MeHg) i.e.

roughly 80% (Margaret et al; 2004205

) .The standards used during this study were hair

certified reference materials (NIES No 13 and IAEA 085) and 72 hair samples that were

obtained from the workers of chlor-alkali sector (Ittehad Chemicals Limited, Kala Shah

Kaku, Sheikhupura and Sitara Chemicals Industries Limited, Faisalabad), dental amalgam

sector (Punjab Dental College and Hospital, Lahore) and control group sector (students,

gardeners etc). Dried washed human hairs, blank and dried certified reference materials

(NIES No 13 and IAEA 085) were used. Washed samples were digested by

autoclave-assisted digestion (closed vials) in 5.0 ml concentrated nitric acid for 90 min at

100 ºC in water bath. This was necessary to break down the Hg – C bond in methyl mercury

(Me-Hg) to form inorganic mercury.

3.3. PREPARATION OF SAMPLES

3.3.1. Waste water sampling

a) Flowing streams/ waste drain channels

Sample liquid of one liter was withdrawn from 3 meter depth. The mixture was

homogenized in polyethylene container and 120 ml of mixed sample was taken sample

bottle containing 20 drops of 5% HNO3.

b) Stagnant liquid reservoirs

One liter liquid samples were taken from four points at least 10 meter apart along

the vertices of a hypothetical rectangle, mixed in polyethylene containers and immediately

transferred in 120 ml sample bottles of polyethylene, already containing 20 drops of 5%

HNO3.The remaining liquid was discarded into the same reservoir.

3.3.2. Sampling of soil matrices

a) Soil samples

For sampling of soil, typically an area of 100 m² was sampled. The sampling areas

were open space land / different types of soil were sampled such as agricultural fields,

forests and from vicinity of potential hot spots. Samples were taken with a clean spoon.

Each soil sample consisted of at least five individual pick-ups, each of them approximately

50 g. All 50 g samples were placed into a bowl in the field, small twigs and other organic

material was removed; the sample was mixed and placed into a zip-lock bag. Total

38

samples size was approximately 200 g. These samples were taken to analytical

laboratory and stored in brown bags until analysis. Before analysis the samples were

air-dried and sieved through a 300 mesh sieve.

b) Sludge

In case of sludge underneath a water channel, a plastic cup attached to a long stick

was used to collect samples weighing 200 gm each. These samples were preserved in

double zipper bags or 120ml flasks through funnel. 20 drops of 5% HNO3 were added to

the sample bottles.

3.3.3. Hair sample preparation

Two steps were performed in the preparation of hair samples;

a) Collection of hair samples

b) Washing of hair samples

c) Closed vials digestion procedure

a) Collection of Hair Samples

72 human hair samples from four different areas with expected mercury exposure

were selected, the areas were;

i. The industry where mercury cell technology is being used

ii. The industry where mercury cell technology has been phased out

iii. Dental college and hospital

iv. General public.

A small bundle of hair from the center of head were tied with thread loosely and cut 1cm

above the root to avoid scalp tissue contamination. The collected hair were stored in

polythene zipper bags. The bags were coded with sticky paper labels for further processing.

b) Procedure for washing of hair samples

Processing was carried out at room temperature. Hair sample were weighed

separately into a 150ml ultra-clean conical flask and 100 ml of detergent solution (1% alkyl

benzene sulfonate in deionized water) was further added in the samples. The flasks

containing samples were whirled for one hour and the final soapy solution was discarded.

The samples follow addition of 100ml of deionized water and shaken, this step was

repeated four times until samples were rinsed thoroughly, during washing the hair samples

39

were shaken vigorously. Hair Samples in the flasks were oven dried at 50 ºC for 12

hours. Followed by the drying the hair samples were optimized with atmospheric humidity

by placing flasks in open for 5 hours (Egeland et al; 2009206

).

c) Closed vials digestion procedure

Total mercury was determined by closed vials digestion procedure. Roughly 10 mg

of hair sample was weighed in two separate 20 ml glass vials. 5ml of concentrated nitric

acid (HNO3) was added into each of the glass vials. The vial was left open under a fume

hood for 20 minutes, then, it was sealed and autoclaved in water bath for 90 minutes at 100

ºC. The glass vial was allowed to cool and the digested solution was weighed. 1ml of each

digested sample was weighed and transferred into 25 ml measuring volumetric flask.

Afterwards, the volume was made up to make a total volume of 25 ml with deionized water

(dilution to 1: 25 v/v). The mercury (total) was measured by CV-AFS.

3.4. TECHNIQUES USED FOR DETERMINING OF

MERCURY

Two sets of instrumentation/ techniques were used for the determination of mercury:

Cold Vapour Atomic Absorption Spectrometry (CV-AAS)

Cold Vapour Atomic Fluorescence Spectrometry (CV-AFS)

The CV-AAS method was employed for soil and waste-water samples analysis

whereas the CV-AFS was used for human hair samples analysis.

3.4.1 Method of Cold Vapour Atomic Absorption Spectroscopy

(CV-AAS)

Mercury was analyzed on Perkin Elmer Analyst 100 atomic absorption

spectrometer fitted with a 100mm quartz tube. The HNO3 digested sample solution was

treated with a reducing agent (20% SnCl2) to convert the ionic mercury into mercury atoms

in the form of fine vapours. Nitrogen gas was purged through the solution at a constant rate

of 1 L/min and then the atomic vapour of mercury was swept into the 100mm glass cell.

The cell consists of a quartz window, transparent to radiation at 253.7nm of the mercury

line that was used for detection. A mercury hollow cathode lamp was used as source. A

series of standards ranging from 0.1-0.9 µg of mercury/Litre and in another range from 1

40

to 10 µg Hg/L were analyzed to establish the 10-point calibration curve. In a similar

way, different samples were analyzed and concentration of Hg was determined.

3.4.1.1. Chemical reagents

i) Mercuric sulphate (Hg2SO4) Fluka

ii) Stannous chloride (SnCl2) Fluka

iii) Sulphuric acid 98%(H2SO4) [Hg <0.0000005%] Fluka

iv) Conductivity water

v) Hg Standard stock solutions (1000 µg/L), Hg Calibration Standards (1-10

µg/L), (0.1-0.9µg/L)

3.4.1.2. Glassware

i) Pyrex™ Measuring flasks (1000 ml,100 ml)

ii) Glass Pipettes (10 ml, 1 ml) (HBG Germany)

iii) Glass Beakers (100 ml,250 ml) (HBG Germany)

iv) Funnel (HBG Germany)

v) China Crucible

3.4.2 Cold Vapour Atomic Fluorescence Spectrometry (CV-AFS)

Cold Vapour Atomic Fluorescence Spectrometry (CV-AFS) is the commonly used

method to analyze very low concentration of mercury (Hg) due to its greater sensitivity,

selectivity and comparatively low cost. CV AFS model [Millennium Merlin- satellite spur

(PSA 10.125), PSA instrumentation, England] was used to determine the concentration of

total mercury (Hg) in hair certified reference materials (CRM IAEA 085, NIES-13) and

human hair samples. The first requirement of the method is conversion of all organic

mercury forms utilizing various digestion and oxidation processes (seven procedures) to

inorganic mercury.

The graphic representation diagram of a continuous – flow vapour generator and

AFS detector is shown in Figure 2. The CV AFS consists of two main parts, the mercury

vapour generator and the AFS detector.

41

Fig 2: Schematic diagram of continuous flow vapour generator and AFS detector.

(Modified from PS Analytical 10.125 Millennium Excalibur, User Manual .Issue No

2.2)

3.4.2.1. Chemical reagents

i. Stannous chloride (SnCl2) 3.0% Fluka

ii. Nitric acid (HNO3) 5.0 % Fluka

iii. Hydrochloric acid (HCl) 10% Fluka

iv. Deionized water

3.4.2.2. Glassware

i. Measuring flasks (1000 ml, 100 ml) HBG Germany

ii. Glass Pipettes (10 ml, 1 ml) HBG Germany

iii. Glass Beakers (100 ml, 250 ml) HBG Germany

iv. Funnel HBG Germany

v. China Crucible

3.4.2.3. General operation procedure

The bore size of the pump tubing and the rotational speed of the pump head

3 %

SnCl2

PC

(recorder)

AFS detector

Hgº

Waste

Hgº(vapour)

Sn2+

+ Hg2+

→ Sn4+

+ Hgº 5 % HNO3 (blank)

or digested

sample

5 %

HNO3

42

determine the flow rate of each stream. In addition, the sample and blank/ acid flow rates

are approximately twice that of the reductant agent (SnCl2). This design helps to control the

chemical reaction and stabilizes the flow patterns thus minimizing the inherent noise

within the system.

3.5. ANALYTICAL PERFORMANCE CHARACTERISTICS

The analytical performance characteristics were evaluated for total mercury as

follows:

3.5.1 Quality control

The quality control system consists of analyzing the blank at start of analysis for

auto zeroing the machine. The second step consists of analysis of CRM NIES No 13 and

CRM IAEA 085 in the beginning of the measurement and after 10 to 15 sample

measurements for slope correction of AFS. The mean total mercury (T-Hg) concentration

obtained from hair certified reference materials (NIES No 13 & IAEA 085) as shown in

table 1 and table 2 was 4.43 µg/g (n =12), which was well within the certified value of 4.42

± 0.2 µg/g for CRM NIES 13 and 22.9 µg/g (n =12), and well within the certified value of

23.2 ± 0.8 µg/g for CRM IAEA 085. The relative standard deviation (RSD %) were 3.3 %

for CRM NIES 13 and 2.4 % for CRM IAEA 085 which are lower than 5%.

Table 1: Determination of T-Hg in CRM NIES -13& CRM IAEA 085

Certified

reference

materials

Average measured value

(µg/g) *x ± SD

% RSD Certified value

(µg/g)

Average

Recovery

(% R)

NEIS 13 4.43 ±0.13 3.3 4.42±0.2 100.2

IAEA 085 22.94 ±0.55 2.4 23.2 ±0.8 98.9

*Results are given as average ± standard deviation (n=12)

3.5.2. Limit of detection (L.O.D)

The instrumental detection limit (L.O.D) was evaluated by running the blank

solution ten times. The detection was then calculated by multiplying the standard deviation

(SD) of ten blank solution run by 3. The result was 0.011 ng/g of the measured solution.

43

The limit of detection (L.O.D) was found well below the level expected for hair sample

(0.03 µg/g).

3.5.3 Calibration data

It is well known that CV-AFS has a very long range of linearity. In this study,

linearity was evaluated over the concentration range of interest for total mercury. The type

of calibration data obtained for mercury is shown in Table 2. Calibration was conducted for

every 10-20 hair sample measurements.

Table 2: Calibration data for mercury

Analyte Concentration rang

(µg/kg)

Equation of Fit* Linear correlation

coefficient (R2)

Hg 0 - 50 Y = 0.0025x + 0.0005 0.9997

*A minimum of five standards was used for calibration line

44

CHAPTER 4

RESULTS AND DISCUSSION

Several products of mercury or derived compounds have been in practice in

commercial and domestic sectors in Pakistan for long time, with the product lifecycle

ultimately ending up as waste, adding up to the environment. The detail of these mercury

products in Pakistan is given in Appendix-1. The chlor-alkali production activities, dental

amalgamation, lime production and certain other manufacturing, handling and ignition

activities are other major causes of mercury release into the atmosphere

Regarding the management of mercury release into the environment, proper

management of products and equipments having mercury or its derivatives, there is no

specific guideline, exact inventory or any legislation in Pakistan.

This study was focused on the preliminary field survey on mercury uses and

releases during the period of January to August, 2008 throughout Pakistan. The specific

aim was the establishment of true inventory of mercury and its products in the environment

of Pakistan.

The major target areas were the followings;

a- Soil and water samples surrounding the chlor-alkali industries.

b- Municipal solid waste and sewerage samples.

c- Hospital waste incinerators.

d- Minerals – Coal and Lime.

e- Human hair samples – from the industries/occupations having mercury

exposure.

45

4.1 RESULTS OF WASTE WATER AND SOLID

SAMPLES FROM THE COUNTRY

To identify the mercury contamination level in the country, 109 samples of

different solid and liquid wastes of chlor-alkali industries, waste water treatment plants,

sugar & paper mills, tanneries, municipal & industrial drains, residues of hospital waste

incinerators, match factories, etc were collected .The results of these samples are given in

the following tables;

In Sindh Province, Hg in solid waste range from 0.02 ppb to 8.84 ppb and its

average is 2.93 ppb. However, Hg in wastewater range from 0.05 ppb to 9.26 ppb and its

average is 2.48 ppb.

In Punjab Province, Hg in solid waste range from 0.40 ppb to 2.70 ppb and its

average is 1.01 ppb. However, Hg in wastewater range from 0.40 ppb to 4.10 ppb and its

average is 2.09 ppb.

In Baluchistan Province, Hg in solid waste range from 1.81 ppb to 7.16 ppb and its

average is 4.15ppb. Hg is also found in raw material like lime stone and coal with

concentration of 2.96 ppb and 5.26 ppb. However, Hg in wastewater is 0.03 ppb.

In KPK Province, Hg in solid waste range from 4.00 ppb to 6.40 ppb and its

average is 5.36 ppb. However, Hg in wastewater range from 1.00 ppb to 6.80 ppb and its

average is 2.75 ppb.

Table 3: Results of samples from Sindh (Karachi etc)

Sr. No. Sampling Point Sample Type Hg (ppb)

1. Korangi dumping waste "D", Karachi Solid waste 3.48

2. Korangi dumping waste "A", Karachi Solid waste 8.84

3. Korangi dumping waste "B", Karachi Solid waste 0.02

4. Korangi dumping waste "C", Karachi Solid waste 1.49

46

5. Malir river wet land sludge, Karachi Solid waste 0.00

6. Municipal sludge ,Karachi Solid waste 0.00

7. Permanent Sludge Lagoon(PSL)

Sludge, Karachi

Solid waste 0.85

8. Civil hospital, korangi, Karachi Waste water 0.00

9. Haji Naimat Ullah Tannery,Karachi Waste water 0.00

10. Hasan square drain ,Karachi Waste water 0.05

11. Inlet of treatment plant effluent, Karachi Waste water 2.41

12. Korangi waste drain (Left),Karachi Waste water 0.00

13. Korangi waste drain (Right),Karachi Waste water 0.00

14. Leachate of solid waste, Karachi Waste water 2.73

15. Malir river wet land water, Karachi Waste water 2.06

16. Modern Tannery, Karachi Waste water 0.32

17. Municipal effluent, Karachi Waste water 0.00

18. Shaheen Tannery, Karachi Waste water 0.00

19. Subhanullah Tannery, Karachi Waste water 0.00

20. Zubair Afzal Tannery, Karachi Waste water 9.26

21. Faran Sugar Mill ,Badin Waste water 0.59

22. Digri Sugar Mill ,Digri Waste water 0000

23. Mehran Sugar Mill, Talhar Waste water 00 00

24. Serri Sugar Mill,Tando Mohammad

Khan

Waste water 0 000

25. Tando Muhammad Khan Sugar Mill

,Tando Mohammad Khan

Waste water 00 00

47

Table 4: Results of samples from Punjab (Lahore, Sheikhupura,

Faisalabad etc)

Sr.No. Sampling Point

Sample Type

Hg

(ppb)

1. Mehmood Booti Dumping Site 1, Lahore Solid waste 1.20

2. Mehmood Booti Dumping Site 2, Lahore Solid waste 0.60

3. Residual waste of incinerated hospital

waste, Children Hospital ,Lahore Solid waste 1.52

4. Ittehad chemicals Outlet 4, Kala Shah

Kaku, Sheikhupura Solid waste 2.70

5. Ittehad chemicals Solid Waste 1, Kala Shah

Kaku, Sheikhupura Solid waste 0.77

6. Ittehad chemicals Solid Waste 2, Kala Shah

Kaku, Sheikhupura Solid waste 0.40

7. Ittehad chemicals Solid Waste 3, Kala Shah

Kaku, Sheikhupura Solid waste 0000

8. Sitara chemicals Solid Waste 1, Faisalabad Solid waste 0.40

9. Sitara chemicals Solid Waste 2, Faisalabad Solid waste 0.50

10. Sitara chemicals Solid Waste 3, Faisalabad Solid waste 1.20

11. ARC sock near Kahna, Hudiarah drain,

Lahore Waste water 0 000

12. Badian road, Hudiarah drain , Lahore Waste water 1.59

13. Main Ferozepur road, Hudiarah drain,

Lahore Waste water 00 00

14. Near Shafi Reso Chem, Hudiarah drain,

Lahore Waste water 0000

15. Azadi chowk, Ravi road,River Ravi, Lahore Waste water 0000

16. Near Taj company, Ravi road, River Ravi,

Lahore Waste water 1.26

17. Shahdra village bridge, Ravi road,River

Ravi,Lahore Waste water 0000

18. Town ship municipal waste drain, Lahore Waste water 0.60

19. Mehmood Booti Drain, Lahore Waste water 3.90

48

20. Dharam pura canal , Lahore Waste water 0000

21. Kot Lakhpat industrial Estate drain, Lahore Waste water 0000

22. Leachate Mehmood Booti Dumping Site

Bund Road 1,Lahore Waste water 4.10

23. Leachate Mehmood Booti Dumping Site

Bund Road 2, Lahore Waste water 3.70

24. Leachate Mehmood Booti Dumping Site

Bund Road 3, Lahore Waste water 2.80

25. Supra Tannery, Lahore Waste water 0000

26. Ittehad chemicals Outlet 1,Kala Shah Kaku,

Sheikhupura Waste water 2.30

27. Ittehad chemicals Outlet 2, Kala Shah

Kaku, Sheikhupura Waste water 0.40

28. Ittehad chemicals Outlet 3, Kala Shah

Kaku, Sheikhupura Waste water 3.10

29. Sheikhupura Municipal Drain, Sheikhupura Waste water 2.10

30. Drain near Sitara chemicals, Faisalabad Waste water 2.40

31. Sitara chemicals effluent1, Faisalabad Waste water 1.10

32. Sitara chemicals effluent 2, Faisalabad Waste water 1.30

33. Sitara chemicals effluent 3, Faisalabad Waste water 0.89

34. Sitara chemicals effluent 4, Faisalabad Waste water 1.34

35. Sitara chemicals effluent 5, Faisalabad Waste water 2.70

36. Nimir chemicals effluent

1,Sheikhpura-Faisalabad Road Waste water 0000

37. Nimir chemicals effluent 2,

Sheikhpura-Faisalabad Road Waste water 0000

38. Nimir chemicals effluent 3,

Sheikhpura-Faisalabad Road Waste water 0000

39. Municipal sewerage, Okara Waste water 0000

40. Yousaf Sugar mill, Shahpur Waste water 0000

49

Table 5: Results of samples from Baluchistan (Quetta etc)

Sr.No. Sampling Point Sample type Hg (ppb)

1. Lime as product , Quetta Solid 0000

2. Lime fuel source (coal) , Quetta Solid 5.26

3. Lime stone as raw material , Quetta Solid 2.96

4. Informal dumping site solid waste "1",Quetta Solid Waste 3.48

5. Informal dumping site solid waste "2", Quetta Solid Waste 7.16

6.

Residue of hospital waste incinerator, Bolan

Medical College & Hospital, Quetta Solid Waste 1.81

7. Quetta city municipal waste sludge, Quetta Waste water 0000

8. Quetta city municipal waste water, Quetta Waste water 0.03

50

Table 6: Results of samples from N.W.F.P (Peshawar etc)

Sr.No. Sampling Point Sample Type Hg

(ppb)

1. Ferrous Waste Product, Peshawar Solid <0.50

2. Ferrous Waste Un-reacted, Peshawar Solid <0.50

3. Hayatabad Dumping solid waste site 1 (Labor

colony),Peshawar Solid Waste 6.40

4. Hayatabad Dumping solid waste site 2,Peshawar Solid Waste 5.70

5. Sludge, industrial estate , Hyatabad, Peshawar Solid Waste 0000

6. Buddhni Nala, Bacha Khan Chowk, Peshawar Waste Water 6.80

7. Hayatabad treatment plant ,Peshawar Waste Water 3.50

8. Treatment Plant Gulbahar, Peshawar Waste Water 3.10

9. Waste water , Afghan Match , Hyatabad, Peshawar Waste Water 2.70

10. Waste water , Khyber Match, Peshawar Waste Water 2.10

11. Waste water ,Ashraf Match, Peshawar Waste Water 0000

12. Waste water ,Ganda Nala, Peshawar Waste Water 5.40

13. Waste water ,Hasan Pharma, Hayatabad , Peshawar Waste Water 3.40

14. Waste water ,Hayatabad Labour colony, Peshawar Waste Water 0000

15. Waste water ,Khyber Teaching Hospital, Peshawar Waste Water 2.40

16. Waste water ,Midway Hotel, Peshawar Waste Water 0000

17. Waste water ,Mohsin Match, Hayatabad , Peshawar Waste Water 2.40

18. Waste water ,Neelam Paper, Peshawar Waste Water 2.60

19. Waste water ,PCSIR Environmental Lab, Peshawar Waste Water <0.80

20. Waste water ,Rapid Car Wash, Peshawar Waste Water 0000

21. Waste water ,Royal PVC raw material ,Hayatabad ,

Peshawar

Waste Water 1.30

22. Waste water ,Sardar Begum Dental College, Ghandara

University , Peshawar

Waste Water 0000

23. Waste water ,Sarhad Board, Hayatabad, Peshawar Waste Water 1.50

24. Waste water ,Sufi Foods, Peshawar Waste Water 0000

51

25. Waste water, industrial estate, Hyatabad, Peshawar Waste Water 3.10

26. Waste water ,Taj Ghee, Hattar, Haripur Waste Water 0000

27. Waste water ,Volta Battery, Hattar, Haripur Waste Water 3.70

28. Waste water , Chinoti Gul Ghee ,Hattar, Haripur Waste Water 0000

29. Waste water ,Hattar Rending,Hattar,Haripur Waste Water 2.10

30. Waste water ,Khyber Lamps, Hattar, Haripur Waste Water 3.60

31. Waste water ,Lateef Ghee, Hattar,Haripur Waste Water 1.50

32. Waste water ,Permanent Paper, Hattar,Haripur Waste Water 3.60

33. Waste water ,Chashma sugar mill, D.I. Khan Waste Water 0000

34. Waste water ,Fouji Corn Complex, Swabi Waste Water 3.40

35. Waste water ,Musarat Shaukat Hospital Complex, Dir Waste Water 0000

36. Waste water ,Pakistan Tobacco Company ,Akora

Khatak

Waste Water 1.90

52

4.1.1 DISCUSSION

The results indicate that all the sectors of society and industry have exposure to

mercury at least to some extent as revealed by the data in above tables. It has become more

of concern because this study touches the narrowly selected windows of samples which

are, but meager representative of real image.

The results also indicate that the maximum mercury concentration is limited to the

solid waste disposal sites in all areas of provinces of Pakistan. The sources contributing to

the higher mercury concentration in municipal solid waste is apparently due to the waste

batteries cells, fluorescent lamps, some switching devices. No doubt, this figure of the

finding is disturbing but on the other hand, the solid waste can be managed more easily and

it spreads much less as compared to liquid waste. The proper disposal or removal of

mercury from the solid waste could be reliable mitigation measure for the toxicity of

mercury. The need is to identify sources adding the maximum mercury in the solid waste,

be it some industry or occupation.

4.2 RESULTS OF MERCURY FROM HUMAN HAIR

SAMPLES

To identify the mercury exposure of the workers in mercury related occupations, 72

human hair samples were obtained from chlor-alkali sector (Ittehad Chemicals Limited,

Kala Shah Kaku, Sheikhupura & Sitara Chemicals Industries Limited, Faisalabad), dental

amalgam sector (Punjab Dental College and Hospital, Lahore) and control group sector

(students, gardeners etc).

The concentrations of total mercury (T-Hg) in hair samples are summarized in

tables 7, 8,9,10 and Figures 3, 3a & 3b.

53

Table 7: Total mercury concentration in human hair samples of

workers in Ittehad Chemicals Limited, Kala Shah Kaku

Sample ID

Total mercury concentration µg/g

(mean ± SD), n = 12

Dry hair sample % RSD

1 ICL PK 275 ± 3.6 1.30

2 ICL PK 143 ± 1.7 1.20

3 ICL PK 1057 ± 17.4 1.65

4 ICL PK 1124 ± 32.26 2.87

5 ICL PK 199 ± 2.46 1.24

6ICL PK 125 ± 2.0 1.40

7 ICL PK 3261 ± 39 1.20

8 ICL PK 9341 ± 76 0.81

9 ICL PK 143 ± 2.0 1.30

10 ICL PK 272 ± 3.0 0.99

11 ICL PK 470 ± 7.0 1.39

12 ICL PK 10.6 ± 0.3 2.80

13 ICL PK 14.7 ± 0.3 1.93

14 ICL PK 517 ± 4.0 0.87

15 ICL PK 725 ± 7.0 0.99

16 ICL PK 87.7 ± 1.6 1.89

17 ICL PK 34.5 ± 1.4 6.48

18 ICL PK 12.2 ± 0.8 6.52

19 ICL PK 10.5 ± 0.5 5.10

20 ICL PK 177 ± 3.0 1.59

21 ICL PK 768 ± 7.0 0.91

22 ICL PK 45.1 ± 0.3 0.74

54

Table 8: Total mercury concentration in human hair samples of

workers in Sitara Chemicals Industries Limited, Faisalabad

Sample ID

Total mercury concentration µg/g

(mean ± SD), n = 12

Dry hair sample % RSD

23 SCL PK 3.32 ± 0.18 5.45

24 SCL PK 2.00 ± 0.08 4.04

25 SCL PK 3.86 ± 0.14 3.75

26 SCL PK 2.57 ± 0.13 5.04

27 SCL PK 20.2 ± 0.4 1.95

28 SCL PK 2.89 ± 0.17 6.13

29 SCL PK 2.36 ± 0.09 4.17

30 SCL PK 2.01 ± 0.12 6.26

31 SCL PK 1.69 ± 0.11 6.56

32 SCL PK 1.71 ± 0.06 4.03

55

Table 9: Total mercury concentration in human hair samples of

technicians/doctors in Punjab Dental College and Hospital,

Lahore

Sample ID

Total mercury concentration µg/g

(mean ± SD), n = 12

Dry hair sample % RSD

33 DCD PK 1.93 ± 0.12 6.56

34 DCD PK 2.47 ± 0.09 3.71

35 DCD PK 2.20 ± 0.13 7.25

36 DCDPK 1.94 ± 0.09 5.05

37 DCD PK 4.68 ± 0.45 9.60

38 DCD PK 3.70 ± 0.22 6.08

39 DCDPK 3.19 ± 0.18 5.75

40 DCD PK 3.00 ± 0.21 7.27

41 DCD PK 3.89 ± 0.22 5.86

42 DCDPK 3.07 ± 0.32 10.50

43 DCD PK 2.31 ± 0.09 5.18

44 DCD PK 1.44 ± 0.11 7.75

45 DCDPK 3.36 ± 0.11 3.52

46 DCD PK 2.20 ± 0.15 7.01

47 DCD PK 4.86 ± 0.36 7.46

48 DCD PK 0.45 ± 0.02 6.20

49 DCD PK 3.60 ± 0.18 5.23

50 DCDPK 2.10 ± 0.12 6.09

51 DCD PK 1.29 ± 0.07 7.40

52 DCD PK 2.15 ± 0.17 8.04

53 DCD PK 1.63 ± 0.05 3.63

72* DCD PK 1.41 ± 0.10 7.62

*(The sample number is inconsistent because one of the sample of the same category was collected at a later time when the serial number had advanced)

56

Table 10: Total mercury concentration in human hair samples of

students and staff of Punjab University, Lahore

Sample ID

Total mercury concentration µg/g

(mean ± SD), n = 12

Dry hair sample % RSD

54 CGS PK 1.29 ± 0.07 5.85

55 GCS PK 0.71 ± 0.05 8.35

56 CGSPK 0.37 ± 0.03 10.4

57 CGS PK 0.41 ± 0.05 13.1

58 CGS PK 0.23 ± 0.01 8.26

59 CGSPK 0.13 ± 0.01 8.99

60 CGS PK 1.25 ± 0.10 8.35

61 CGS PK 0.15 ± 0.01 7.93

62 CGS PK 0.12 ± 0.01 9.30

63 CGS PK < 0.03

64 CGS PK < 0.03

65 CGS PK < 0.03

66 CGS PK 0.52 ± 0.05 10.89

67 CGS PK 0.87 ± 0.05 6.01

68 CGS PK < 0.03

69 CGS PK 1.91 ± 0.10 5.51

70 CGS PK 4.73 ± 0.11 2.34

71 CGS PK 0.89 ± 0.05 5.75

57

Fig 3 Concentration of T-Hg (µg/g) in human hair samples ranked for their

concentration.

Fig.3a: Concentration of T-Hg (µg/g) in human hair samples (n=72). The line indicates

the WHO value of 2 µg/g.

0

100

200

300

400

500

600

700

800

900

1000

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64 67 70

sample

mg

Hg

/ K

g h

air

0.1

1

10

100

1000

10000

1 7 13 19 25 31 37 43 49 55 61 67Sample

ug

Hg

/g

0.1

1

10

100

1000

10000

C C C C C C C C CCA1

CA1

CA1

CA1

CA1

CA1

CA1

CA1

CA1

CA1

CA1

CA1

CA2

CA2

CA2

CA2 D D D D D D D D D D D

mg H

g/k

g h

air

control group chlor alkali factory (Lahore)chlor-alkali

factory 2dental hospital group

58

Fig. 3b: Concentration of T-Hg (µg/g) in human hair samples (n=72). CA1 is Ittehad

Chemicals, Sheikupura; CA2 is Sitara Chemicals, Faisalabad. Dental represents the

samples from workers in dental surgery facilities.

Tables 7,8,9,10 and Fig. 3 show the results for total mercury (T-Hg) in 72 hair samples

obtained from four (4) groups as follows;

Group No (1): The highly suspected group of 22 people was selected from the

workers of Ittehad Chemicals Limited, Kala Shah Kaku, Sheikupura as the said

industry still uses mercury cell technology. The human hair samples 1ICL PK to 22

ICL PK were collected from this group.

Group No (2): The moderately exposed suspects were selected from Sitara

Chemical Industries Limited, Faisalabad – which has abandoned the mercury cell

technology. The human hair samples 23 SCL PK to 32 SCL PK were collected

from this group.

Group No (3): Another moderately exposed suspect group was chosen from the

workers of Punjab Dental College and Hospital; Lahore .The human hair samples

33 DCD PK to 53 DCD PK and No 72 DCD PK were collected from this group.

Group No (4): The control group human hair samples 54 CGS PK to 71 CGS PK

were collected from students and staff of Punjab University, Lahore.

0.01

0.1

1

10

100

1000

10000

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5

mg

Hg

/ K

g h

air

Control CA1 CA 2 Dental

59

All the human hair samples above were collected from the Lahore, Sheikhupura and

Faisalabad area as shown in Fig 4.

Fig. 4: Location of study area in Punjab Province, Pakistan

Group No.1 hair samples showed particularly high concentration of total mercury

(n=22, mean 818 µg/g, median 177 µg/g of a range between 3.32 µg/g and 9341 µg/g) as

shown in table 5. These values of T-Hg obtained exceed the normal value (2.0 µg/g)

recommended by the WHO (1990207

) by orders of magnitude. The high total mercury

concentration could be as a result of the fact that the workers come in contact with mercury

cells and mercury leakage in their work place for more than eight (8) hours on a day’s work

during maintenance of these cells. It is pertinent to mention here that the information was

also obtained from all 72 people of four groups by filling up anonymous questionnaire

which is shown in Appendix 2 .The duly filled-in anonymous questionnaire is also shown

in Appendix 3.

The results of T-Hg concentration achieved in group No. 2 are lower than those in

group No. 1 [n=10, mean 4.36, median 2.30 and a range between 1.69 µg/g – 20.2 µg/g]. It

can be seen that the results for group No.2 mean and median exceed the normal value (2.0

µg/g) recommended by the WHO (1990207

) as well. While, this limited dataset is inclined

60

by the one large value, it should be noted that the lowest concentration is just lower the

2.0 µg/g and no value is below 1.0 µg/g.

For group No 3, the total mercury concentration obtained for the workers in the

dental hospital (n=22) showed a mean value of 2.59 and a median of 2.26 µg/g and a range

between 0.45 µg/g to 4.86 µg Hg per gram which shows that most of the hair samples in

this group exceeded the normal value (2.0 µg/g) recommended by the WHO (1990207

).

These results may be recognized to the exposure to the amalgam.

The total mercury (T-Hg) results for group No.4, the control group (n=18) are

between below detection limit (<0.03 µg/g) and 4.73 µg/g. The mean value is 0.76 µg/g

and median 0.39 µg/g, both are extensively lower (p<0.05) than those of the dental hospital

and the workers from the chlor-alkai factories. In addition, most of the hair samples in this

group show lower concentration of total mercury (T-Hg) than the normal value (2.0 µg/g)

recommended by the WHO (1990207

).

It can be seen that in human hair sample groups 1, 2 and 3, most of the hair samples

(T-Hg concentration) exceed the normal value (2.0 µg/g) recommended by the WHO

(1990207

). This can be related to prolonged exposure of workers to the mercury vapour.

Apparently, the longer is the duration of exposure, the higher is the value of total mercury

(T-Hg) found in their hair samples. For example, in group No.1, the workers come into

contact with mercury and mercury vapour at the work place (Ittehad Chemicals Limited

employing chlor-alkali process using mercury cell technology) thus resulting in high

concentration of T-Hg in their hair samples.

In group No.2, (the workers of the factories who have completely phased out

Mercury cell technology) the high concentration of T-Hg in hair samples could be due to

exposure to the contaminated areas. The Group No. 3 although, having been in close

vicinity to mercury usage, has even lower levels of mercury, owing to better occupational

practices and proper knowledge. However, in group No.4, lower concentration of total

mercury in hair samples were recorded as a result of limited exposure to mercury involving

students and staff at Punjab University, Lahore.

61

4.2.1. Comparison with other studies

In comparison of this study with other data obtained from similar studies as shown

in table 9, the average total mercury concentration in human hair samples for Pakistani

chlor-alkali factory workers are extremely high, especially from the one location. Several

hair samples had values above 1000 µg/g, which are the highest values ever reported. The

hair from workers of a different chlor- alkali factory site had much lower mercury values,

although still at elevated levels. Pakistani health workers had high levels of mercury

compared to the general public (2.62 ± 0.16 µg/g) and Pakistani general people (0.97 ±

0.04 µg/g.

62

Table 11: Comparison of T-Hg concentrations from this study with

other different studies of different exposed populations

worldwide

Location n

Mean ±

SD

(µg/g)

Range

(µg/g) Comments

References

Tucurui, Para,

Brazil

125 35.0 0.9-240 Fishermen Leino and

Lodenius

(1995208

)

Palawan

Philippines

130 3.7 0.1 – 18.5 Hg mining impacted area Williams et

al. (2000209

)

Kuwait 100 4.181 - Fishermen Al-Majed

and Preston

(2000210

)

Diwalwal,

Philippines

316 4.14 0.03-37.76 Gold amalgamation area Drasch et al.

(2001211

)

Rio Branco,

Brazil

2318 2.418 ±

0.850

- Urban population De Oliveira

Santos et al

(2002212

)

Jacareacanga,

Para, Brazil

205 8.6 0.3-83.2 Brazilian Amazon

riverine community

Crompton et

al. (2002213

)

Ten cities in

Japan

8665 1.82

(GM*)

0.02 –

29.37

Yasutake et

al. (2004214

)

Cambodia 94 3.1 (GM)

7.3 (GM)

0.54-190

A source other than fish

may be responsible for

high Hg in some

Cambodians

Tetsuro, A.

et al

.(2005215

)

Madeira River

B., Amazon ,

Brazil

713 15.22 ±

9.60

5.99-150

Riverside population Bastos et al.

(2006216

)

Wujiazhan 108 3.44 The river was polluted Zhang and

63

town,

northeast

China

(AM**)

0.648

(GM*)

0.16-199 with Me-Hg by industrial

wastewater discharge

Wang

(2006217

)

DSX,

Wanshan

49 5.5 ± 2.7 1.5-16 Mercury mining area Ping Li

(2009218

)

XCX,

Wanshan

36 3.3 ± 1.4 1.6-9.4 Mercury mining area Ping Li

(2009218

)

Chlor-Alkali /

Pakistan

(SCL)

10 Mean

4.36

Median

2.30

1.69 – 20.2 Pakistani Chlor-Alkali

factory(Faisalabad)

Chlor-Alkali /

Pakistan

(ICL)

22 Mean

818

Median

177

3.3 - 9341 Pakistani Chlor-Alkali

factory (Lahore)

Pakistani

Health

worker/

Pakistan

22 Mean

2.59

Median

2.26

0.45- 4.86 Dental Hospital (

Pakistan /Lahore)

Punjab

University

(Lahore

/Pakistan)

18 Mean

0.76*

Median

0.39*

<0.03-4.73 Pakistani Control group

(student/staff

population)

*< 0.03 µg/g is the l.o.d and for the statistics, value was set to half the l.o.d. (0.015 µg/g)

* Geometric mean. ** Average mean

64

4.3. DATA FROM THE MARKETS OF LAHORE,

KARACHI, QUETTA, KASUR, RAWALPINDI AND

RESEARCH INSTITUTES

The data of mercury and mercury compounds were also collected by the field

survey of different chemical stores, medical stores, scientific stores, research institutes and

waste water treatment plants from many cities of the country. The data showed that there is

no policy and guidelines for the use of mercury at commercial and research level. The

detail of these data is given in the following tables;

Table 12: Cheap Chemicals Store, Lahore

Table 13: Akbari Chemicals Store, Lahore

Sr.No. Mercury Compounds Qty

1 Commercial Mercury 99.9% 100 kg

Sr.No. Mercury Compounds Qty

1 Mercury (Hg) (commercial) 10 kg

2 Mercuric Chloride (HgCl2) 10 kg

3 Mercuric Iodide (HgI) (red) 15 kg

4 Mercuric Nitrate (HgNO3) 5 kg

5 Mercuric Oxide (HgO) Yellow & Red 15 kg

6 Mercuric Sulphate (HgSO4) 10 kg

7 Mercuric Sulphide (HgS) (red) 800 gm

8 Mercurous Acetate (C4 H6 Hg2 O2) 10 kg

9 Mercurochrome(

2,7-Dibromo-4-hyroxymercurifluoresceine

disodium salt) containing 24-27% Hg

20 kg

65

Table 14: Merck (Pvt.) Ltd, Lahore

Table 15: Nawab Chemical Store, Karachi

Sr.No. Mercury Compounds Qty

1 Commercial Mercury 99.9% 100 kg

Table 16: Dawawala Chemical Corporation, Karachi

Sr.No. Mercury Compounds Qty

1 Mercuric Chloride (HgCl2) 15 kg

Table 17: Mohammad Jamil Sons, Karachi

Table 18: Rahat Chemicals, Quetta

Sr.No. Mercury Compounds Qty

1 Mercuric Chloride (HgCl2) 500 gm

2 Mercuric Sulphate (HgSO4) 3 kg

3 Mercuric Nitrate (HgNO3) 1 kg

Sr.No. Mercury Compounds Qty

1 Mercuric Chloride (HgCl2) 1kg

2 Mercuric Sulphate (HgSO4) 2.5 kg

3 Mercuric Bromide (HgBr) 1 kg

4 Mercuric Nitrate (HgNO3) 750 gm

Sr.No. Mercury Compounds Qty

1 Commercial Mercury 99.9% 60 kg

66

Table 19: Alam Instruments & Chemicals, Quetta

Sr.No. Mercury Compounds Qty

1 Mercuric Chloride (HgCl2) 2 kg

2 Mercuric Sulphate (HgSO4) 5 kg

Table 20: Kasur Tannery Waste Management Agency (KTWMA),

Kasur

Sr.No. Mercury Compounds Qty

1 Mercuric Sulphate (HgSO4) 1.5 kg

Table 21: Shalimar Scientific Store, Rawalpindi

Sr.No. Mercury & Mercury Containing

Products Qty

1 Analytical Grade Pure Mercury 20 kg

2 Normal Grade Pure Mercury 20 kg

3 Thermometer 110 oC 100 Nos

4 Barometer 5 Nos

Table 22: Scientific Home, Rawalpindi

Sr.No. Mercury & Mercury Containing

Products

Qty

1 Analytical Grade Pure Mercury 13 kg

2 Normal Grade Pure Mercury 18 kg

3 Mercuric Bromide (HgBr) 4 kg

4 Mercuric Sulphate (HgSO4) 2 kg

5 Mercuric Chloride (HgCl2) 3 kg

67

Table 23: Nobel Scientific Traders, Rawalpindi

Sr.No. Mercury & Mercury Containing

Products Qty

1 Analytical Grade Pure Mercury 7 kg

2 Normal Grade Pure Mercury 10 kg

3 Mercuric Sulphate (HgSO4) 1 kg

4 Mercuric Chloride (HgCl2) 2 kg

5 Thermometer 110 oC 60 Nos

6 Barometer 4 Nos

Table 24: Medi Plus Chemist, Rawalpindi

Table 25: Shaheen Chemist, Rawalpindi

Sr.No. Mercury & Mercury Containing

Products

Qty

(Nos)

1 Master Thermometer 100

2 Safety Thermometer 35

3 B.P Apparatus 7

Table 26: Khattak Chemist, Rawalpindi

Sr.No. Mercury & Mercury Containing

Products

Qty

(Nos)

1 Master Thermometer 72

2 Safety Thermometer 12

3 B.P Apparatus 4

Sr.No. Mercury & Mercury Containing

Products

Qty

(Nos)

1 Master Thermometer 500

2 Safety Thermometer 300

3 B.P Apparatus 15

68

Table 27: City Surgical, Rawalpindi

Table 28: The Mall Chemist, Rawalpindi

Table 29: W. Watson Chemist, Rawalpindi

Sr.No. Mercury & Mercury Containing

Products

Qty

(Nos)

1 Master Thermometer 200

2 Safety Thermometer 800

3 B.P Apparatus 4

Table 30: Institute of Chemistry, University of the Punjab, Lahore

Sr.No. Mercury compounds Qty

1 Mercury Metal 24.5 g

2 Mercury Chloride 600 gm

3 Mercury Cyanide 165 gm

4 Mercury Iodide 1.7 kg

5 Mercury Iodide (red) 750 gm

6 Mercury Oxide (Yellow) 300 gm

Sr.No. Mercury & Mercury Containing

Products

Qty

(Nos)

1 Master Thermometer 40

2 B.P Apparatus 5

Sr.No. Mercury & Mercury Containing

Products

Qty

(Nos)

1 Master Thermometer 100

2 Safety Thermometer 30

3 B.P Apparatus 5

69

Table 31: Pakistan Council for Scientific and Industrial Research

(PCSIR), Lahore

Sr.No. Mercury Compounds Qty

1 Mercuric Sulphate (HgSO4) 2 kg

The data collected from the markets shows (in the above tables) that mercury is

being used as metallic mercury and in many products and compounds like thermometers,

BP apparatus, analytical grade pure mercury, commercial mercury, mercuric sulphate,

mercury chloride, mercury cyanide, mercury iodide, mercury oxide, mercuric bromide,

mercuric nitrate, mercuric sulphide, mercurous acetate , mercurochrome etc.

During the survey, it has also been observed that commercial mercury is being sold

by the herbal merchant stores in many parts of the country. Further, the record of this

commercial mercury is not available with custom department. So, it is assumed that

commercial mercury is being imported illegally from neighboring countries.

4.4. QUANTIFICATION OF MERCURY RELEASES

Information and data were collected during the survey and desk study. The estimated

amount of mercury use and release in Pakistan were discussed by each category set under

UNEP’s Toolkit as the following description;

4.4.1. Extraction and use of fuels and other energy sources

This category refers to coal combustion in large power plants, mineral oils

(extraction, refining and use), natural gas (extraction, refining and use), other fossil fuels

(extraction and use), biomass fired power, heat production and geothermal power

production. However, the focus of this study was on local production of coal, mineral oils

and natural gas for the quantification of release of mercury in the country. The production

of coal in Pakistan was 2091310 metric tons during July, 07 to June, 08.The province wise

detail is given in table 25.However, the mineral oil production and use of gasoline, diesel

and other distillate were 1610762 metric tons and 5676182 metric tons respectively during

2008.

70

Table 32: Local production of coal in Pakistan (July 07 to 30 June,

2008)

Sr.No. Name of Province Quantity (in metric tons)

1 Balochistan 222845

2 Punjab 553453

3 Sindh 1072053

4 N.W.F.P 23570

5 FATA 219389

Total 2091310

Table 33: Toolkit calculation for mercury releases from coal sector

Category name

Extraction and use of fuels/energy sources

Output factors Output

Type of Transfer % Total Kg

air output distribution factor 1 1045

water output distribution

factor 0 0

land output distribution factor 0 0

Sub category name Coal combustion in

large power plants

Product output distribution

factor 0 0

waste output distribution

factor 0 0

disposal output distribution

factor 0 0

Total 1045

Output scenario Emis. Red. Devices:

None Mass balance 0

Exist Yes

Input factor by

default 0.05-0.5 g Hg/t

Input factor x 1000

Activity rate 2091310 T/year

Hg input 0.5 g Hg/t

Hg input

calculation 1045 Kg/year

71

Table 34: Toolkit calculation for mercury releases from extraction of

crude oil

No File 1

Output factors Output Kg

No source 21 Type of transfer % Total

No Category 51 air output distribution factor 1 0.0161

Category

name

Extraction and use of

fuels/energy sources water output distribution factor

0 0,0000

Sub category

no 513 land output distribution factor 0 0,0000

Sub category

name

Mineral oils - extraction,

refining and use Product output distribution factor

0 0,0000

Phase 1 Extraction waste output distribution factor 0 0,0000

Phase 2 0 disposal output distribution factor 0 0,0000

Phase 3 0 Total 0.0161

Output

scenario 0 Mass balance 0

Exist Yes

Input factor by

default 0.01 mg Hg/t

Input factor x 1000000

Activity rate 1610762 T/year

Hg input 0.01 mg Hg/t

Hg input

calculation 0.01610762 Kg/year

72

Table 35: Toolkit calculation for mercury releases from use of

gasoline, diesel and other distillates

No File 2

Output factors Output Kg

No source 27 Type of transfer % Total

No Category 51 air output

distribution factor 1 567

Category name Extraction and use of

fuels/energy sources

water output

distribution factor 0 0,0000

Sub category no 513 land output

distribution factor 0 0,0000

Sub category name

Mineral oils -

extraction, refining

and use

Product output

distribution factor 0 0,0000

Phase 1

Use of gasoline,

diesel and other

distillates

waste output

distribution factor 0 0,0000

Phase 2 Uses (other than

combustion)

disposal output

distribution factor 0 0,0000

Phase 3 0 Total 567

Output scenario 0 Mass balance 0

Exist Yes

Input factor by default 1 – 100 mg Hg/t

Input factor x 1000000

Activity rate 5676182 T/Year

Hg input 100 mg Hg/t

Hg input calculation 567 Kg/year

4.4.1 Natural gas - extraction, refining and use

The fossil fuel used for Pakistani household cooking is predominantly natural gas.

Natural Gas (CNG) for vehicles and cooking by using Liquefied Petroleum Gas (LPG) are

being used in Pakistan. The consumption of natural gas in Pakistan was estimated at 29.54

billion cubic meters during 2008.

73

Table 36: Toolkit calculation for mercury releases from natural gas

4.4.2. Primary metal production-small scale gold mining

This category refers to primary mercury ores, gold and silver extraction with

mercury amalgamation processes, zinc, copper, lead, aluminum extraction and initial

processing, gold extraction and initial processing by methods other than mercury

amalgamation, other non-ferrous metals and primary ferrous metal production.

Pakistan is an agricultural country. There are very large numbers of minerals

occurrences but only a few proven (measured reserves) metallic minerals deposits.

No File 3

Output factors output

No source 33 Type of transfer % Total Kg

No Category 51 air output

distribution factor 1 11.8160

Category name Extraction and use of fuels/energy

sources

water output

distribution factor 0 0,0000

Sub category

no 514

land output

distribution factor 0 0,0000

Sub category

name

Natural gas - extraction, refining

and use

Product output

distribution factor 0 0,0000

Phase 1 /Use of pipeline gas (consumer

quality)

waste output

distribution factor 0 0,0000

Phase 2 0 disposal output

distribution factor 0 0,0000

Phase 3 0 Total 11.8160

Output

scenario 0 Mass balance 0

Exist Yes

Input factor by

default 0.03 - 0.4 µg Hg/Nm

3 gas

Input factor x 1, 000, 000,000

Activity rate 29, 540, 000,000 m3/Year

Hg input 0.4 µg Hg/Nm3 gas

Hg input

calculation 11.816 Kg/year

74

Chromite occurs in Khyber Pakhtoonkhawa and Baluchistan. Its production varies from

20,000 tons to 60,000 tons per year. So far, there is no primary mercury production in

Pakistan context .There are no production activities of other minerals and materials with

mercury impurities in Pakistan, except the production of lime and bricks. In this

perspective, some people use mercury amalgamation process for the extraction of placer

gold in some places along Indus River upstream of Tarbela Lake. There is no data available

for this sector.

4.4.3. Production of other minerals and materials with mercury

impurities

This category refers to production of cement, production of pulp and paper, and

production of lime and aggregates with light weight. All these products exist in Pakistan.

The cement production was estimated at 25 million tons during 2007-08.

75

Table 37: Toolkit calculation for mercury releases from cement

production

No File 15

Output factors Output (Kg)

No source 54 Type of transfer % Total

No Category 53 air output

distribution factor 1 2500

Category

name

Production of other minerals

and materials with mercury

impurities

water output

distribution factor 0 0

Sub category

no 531

land output

distribution factor 0 0

Sub category

name Cement production

Product output

distribution factor 0 0

Phase 1 cement production waste output

distribution factor 0 0,00

Phase 2 0 disposal output

distribution factor 0 0

Phase 3 0 Total 2500

Output

scenario 0 Mass balance 0

Exist Yes

Input factor

by default 0.02 -0.1 g Hg/t cement

Input factor x 1000

Activity rate 25 000 000 T/Year

Hg input 0.1 g Hg/t cement

Hg input

calculation 2500 Kg/year

4.4.4 Intentional use of mercury in industrial processes

This category refers to the use of mercury technology in chlor-alkali production,

Vinyl Chloride Monomer (VCM) and acetaldehyde production with mercury catalyst,

production of chemicals and polymers with mercury.

Although Pakistan has approximately 2 billion tons of copper ore (0.4 % to 0.65%

76

Cu) in Balochistan, yet, only one deposit i.e. Sandak copper deposit is being mined

which produces only 15000 tons of copper blister with small amounts of gold, silver and

molybdenum. Small quantities of Dilband lateritic iron ore (approximately 100,000 tons of

ore) were being mined. There is no other metallic deposit being mined. Lead –Zinc ore

deposit of Gunga, Balochistan may be mined in near future.

Mercury cell technology in chlor-alkali production is the major intentional use of

mercury in industrial processes in Pakistan. Total capacity of chlor-alkali industries in

Pakistan is 322,000 M. Tons out of which 16.4% is based on mercury cell technology. In

Pakistan the status of mercury use in chlor-alkali industry is as below;

Table 38: Chlor-alkali industry in Pakistan

Sr.No. Name of Industry Capacity

(tons) Basis Status

1

Sitara Chemical

Indutries

Limited,Faisalabad

180,000

100% Production is

based on Membrane

Cell

0

2

Ittehad Chemicals

Limited, Kala

Shah Kaku,

Sheikhupura

132,000

60% Production is

based on Membrane

Cell

52800 Tons

capacity on

mercury cell

3 Nimir Chemicals,

Sheikhupura 10,000

100% Production is

based on Membrane

Cell

0

77

Table 39: Toolkit calculation for mercury releases from chlor-alkali

sector

No File 4

Output factors output

No source 60 Type of transfer % Total Kg

No Category 54 air output distribution

factor 0 0,0000

Category name

Intentional use of

mercury in industrial

processes

water output

distribution factor 0 0,0000

Sub category no 541 land output

distribution factor 0 0,0000

Sub category

name

Chlor-alkali

production with

mercury-technology

Product output

distribution factor 0 0,0000

Phase 1

Chlor-alkali

production with

mercury-technology

waste output

distribution factor 1 21 120

Phase 2 0 disposal output

distribution factor 0 0,0000

Phase 3 0 Total 21,120

Output scenario

Hg unaccounted for

presented under

"Sector specific

treatment/disposal"

Mass balance 0

Exist Yes

Input factor by

default 25-400 g Hg/t

Input factor x 1000

Activity rate 52800 T/Year

Hg input 400 g Hg/t

Hg Output

Calculation 21120 Kg/year

78

4.4.5 Consumer products with intentional use of mercury

The category refers to consumer products containing mercury including

thermometers with mercury, light sources with mercury, electrical switches and relays with

mercury, batteries with mercury, paints containing mercury, biocides and pesticides

containing mercury, cosmetics, pharmaceuticals for human and veterinary uses, and

related products with mercury.

So far, no inventory exists about the mercury being used in the above described

products except thermometers, light sources and batteries in Pakistan. Moreover, there is

no record of thermometers, light sources and batteries having been used and how many

thermometers, light sources and batteries have been distributed or disposed of within the

country. Based on history, it was understood that such mercury thermometers had been

used as medical thermometers, ambient air temperature thermometers in both industrial

equipment and chemical laboratories. Light sources had been used in compact fluorescent

lamps and batteries are being used to power electrical devices, i.e. radios, clocks, cameras

and toys throughout the country.

Besides information on thermometers, light sources and batteries containing

mercury, there is no information related to the quantity of other consumer products i.e.

electrical and electronic switches, paints, biocides and pesticides, cosmetics,

pharmaceuticals for human and veterinary purposes and related products imported into

Pakistan or having been disposed of neither on a yearly basis nor over a specific period of

time. So, the calculation of the releases of mercury from these types of products is not

available. However, the custom import data of thermometers, fluorescent tubes (double

end) and fluorescent lamps, alkaline, other than button cell shapes, mercury oxide (all

sizes) also called mercury-zinc cells were 310,365 Nos,5,613,181 Nos, 360,866 Nos,

1573 tons and 0.462 tons respectively during 2008.

79

Table 40: Toolkit calculation for mercury releases from

thermometer with mercury

No File 5 Output factors output

No source 66 Type of transfer % Total Kg

No Category 55 air output distribution

factor 0.2 93. 095

Category name

Consumer

products with

intentional use of

mercury

water output

distribution factor 0.4 186.219

Sub category no 551 land output

distribution factor 0.4 186.219

Sub category name Thermometers

with mercury

Product output

distribution factor 0 0

Phase 1 Production waste output

distribution factor 0 0.00

Phase 2 Medical

thermometers

disposal output

distribution factor 0 0

Phase 3 0 Total 465

Output scenario 0 Mass balance 0

Exist Yes

Input factor by default 0.5-1.5 g Hg/t

Input factor x 1000

Activity rate 310,365 items /

year

Hg input 1.5 g

Hg/item

Hg input calculation 465 Kg/year

80

Table 41: Toolkit calculation for mercury releases from fluorescent

tubes (double end)

No File 6

Output factors Output

No source 80 Type of transfer % Total Kg

No Category 55 air output distribution

factor 0.2 11.22636

Category name

Consumer products with

intentional use of

mercury

water output distribution

factor 0.4 22.45272

Sub category no 553 land output distribution

factor 0.4 22.45272

Sub category

name

Light sources with

mercury

Product output

distribution factor 0 0

Phase 1 Use & disposal waste output distribution

factor 0 0,00

Phase 2 Fluorescent tubes

(double end)

disposal output

distribution factor 0 0

Phase 3 0 Total 56

Output scenario

No separate collection.

Waste handling

controlled

Mass balance 0

Exist Yes

Input factor by

default 10 - 40 mg Hg/item

Input factor x 1000000

Activity rate 5613180 items / year

Hg input 10 mg Hg/item

Hg input

calculation 56.1318 Kg/year

81

Table 42: Toolkit calculation for mercury releases from metal halide

lamps

No File 7

Output factors Output Kg

No source 85 Type of transfer % Total

No Category 55 air output distribution factor 0.2 1.80433

Category name

Consumer products

with intentional use of

mercury

water output distribution

factor 0.4 3.60866

Sub category no 553 land output distribution

factor 0.4 3.60866

Sub category

name

Light sources with

mercury

Product output distribution

factor 0 0

Phase 1 Use &disposal waste output distribution

factor 0 0.00

Phase 2 Metal halide lamps disposal output distribution

factor 0 0

Phase 3 0 Total 9

Output scenario 0 Mass balance 0

Exist Yes

Input factor by

default 25 mg Hg/item

Input factor x 1000000

Activity rate 360866 items / year

Hg input 25 mg Hg/item

Hg input

calculation 9.02165 Kg/year

82

Table 43: Toolkit calculation for mercury releases from alkaline,

other than button cell shapes

No File 8

Output factors output

No source 96 Type of transfer % Total Kg

No Category 55 air output

distribution factor 0.2 78.65

Category name

Consumer products

with intentional use

of mercury

water output

distribution factor 0.4 157.3

Sub category no 554 land output

distribution factor 0.4 157,3

Sub category

name

Batteries with

mercury

Product output

distribution factor 0 0

Phase 1 Use & disposal waste output

distribution factor 0 0,00

Phase 2 Alkaline, other than

button cell shapes

disposal output

distribution factor 0 0

Phase 3 0 Total 96 393

Output scenario 0 Mass balance 0

Exist Yes

Input factor by

default 0.25

Kg Hg/t

batteries

Input factor x 1

Activity rate 1573 T/Year

Hg input 0.25 Kg Hg/t

batteries

Hg input

calculation 393.25 Kg/year

83

Table 44: Toolkit calculation for mercury releases from mercury

oxide (all sizes) also called mercury-zinc cells

No File 9

Output factors Output Kg

No source 92 Type of transfer % Total

No Category 55 air output

distribution factor 0.2 29.568

Category

name

Consumer products with

intentional use of mercury

water output

distribution factor 0.4 59.136

Sub category

no 554

land output

distribution factor 0.4 59.36

Sub category

name Batteries with mercury

Product output

distribution factor 0 0

Phase 1 Use & disposal waste output

distribution factor 0 0,00

Phase 2

Mercury oxide (all sizes);

also called mercury-zinc

cells

disposal output

distribution factor 0 0

Phase 3 0 Total 147

Output

scenario

No separate collection.

Waste handling controlled Mass balance 0

Exist Yes

Input factor

by default 320 Kg Hg/t batteries

Input factor x 1

Activity rate 0.462 T/Year

Hg input 320 Kg Hg/t batteries

Hg input

calculation 147.84 Kg/year

84

4.4.6 Other intentional products/process uses

This category is referring to various products including amalgam fillings,

manometers and gauges, laboratory chemicals and equipment, and others. In Pakistan

context, mercury metal use in religious rituals does not exist. Beside this, for mercury use

in manometers and gauges, laboratory chemicals and equipment, we have no information

and data, either on the origin and quantity imported, or where supplied. Nevertheless, it is

known that such products have been used in health care (manometers and gauges) and

laboratories. However, the custom import data of elemental mercury for dental amalgam

was 5779 Kg during 2008.

4.4.6.1 Source description

Mercury may be released to water, air and wastes during the utilization and disposal

of amalgam fillings mainly at the time of insertion of fillings and the teeth removal

containing fillings. The release of mercury may also be happen after the death of a person

with fillings, e.g. dental amalgams.

In Pakistan the year when the dental clinics using mercury amalgams started

operating remains unknown. Most of the dental clinics are operated by private sector and

only a few by public sector. Most dental clinics have from one to four chairs in operation

and other few dental clinics may have up to 10 chairs.

There are several types of tooth filling materials in use in Pakistan including

amalgam, composite, glass ionomer cement, poly carboxylate cement, and ceramic.

Pakistani people who go to dental clinics prefer to use composite for filling their tooth

rather than amalgam.

According to dentists report, it is known that amalgam is usually supplied in two

forms either (1) mercury as pure form with a powder mix of the other metals, which mixed

in the clinic after weighing; or (2) as small capsules possessing mercury metal and the

metal powder in the right proportions and only required to be mixed in the clinic, before

filling the cavity in the tooth.

85

Table 45: Toolkit calculation for mercury releases from other

intentional product/process use

No File 10

Output factors Output Kg

No source 147 Type of transfer % Total

No Category 56 air output distribution

factor 0.2 1155.8

Category name

Other intentional

product/process

use

water output

distribution factor 0.4 2311.6

Sub category

no 565

land output

distribution factor 0.4 2311.6

Sub category

name

Miscellaneous

product uses,

mercury metal

uses, and other

sources

Product output

distribution factor 0 0

Phase 1 Others waste output

distribution factor 0 0.00

Phase 2 0 disposal output

distribution factor 0 0

Phase 3 0 Total 5779

Output

scenario 0 Mass balance 0

Exist Yes

Input factor by

default 0 0

Input factor x 1

Activity rate 5779 T/year

Hg input 1 Kg Hg/T

Hg input

calculation 5779 Kg/year

86

4.4.7 Production of recycled metals (secondary metal production)

This group indicates the mercury release from the production of recycled metals

regarded as secondary metal production. There are three types of sub-categories considered

in this sector including (1) production of recycled mercury, (2) production of recycled

ferrous metal (iron and steel) and (3) production of other recycled metals. In Pakistan, the

secondary metal production is carried out only for scraped iron, aluminum, copper and

lead.

4.4.8 Waste incineration

This category refers to any waste that is fed to incinerators regardless of installation

of air pollution control system. As indicated in the UNEP’s Toolkit, there are five types of

waste incineration sub-categories addressed including, incineration of municipal, wastes,

incineration of medical waste, incineration of hazardous waste, incineration of sewage

sludge and burning (informal incineration) of waste. In this regards and based on Pakistan

context, the waste incineration in Pakistan can be addressed only to one type i.e. medical

waste incineration. In Pakistan the total quantity of medical waste incinerated is 4118 tons

per year. The detail is given below;

About 1000 tons medical waste is incinerated per year in Karachi (Sindh EPA).

Total quantity of medical waste incinerated in Quetta city is 730 tons per year (EPA

Balochistan). Total quantity of incineration of medical waste per year in Peshawar city is

1314 tons per year (EPA, NWFP). Total quantity of medical waste incinerated per year in

Punjab (EPD, Punjab) is given below;

87

Table 46: Quantity of medical waste incinerated per year

Sr.No. Name of hospital Mass of waste

incinerated/year

1 Shahlimar Hospital, Lahore 480 Tons

2 Sheikh Zaid Hospital, Lahore 225 Tons

3 Shaukat Khanam Memorial

Hospital, Lahore 60 Tons

4 National Hospital, Faisalabad 7.50 Tons

5 Sanate Rafeel, Faisalabad 7.50 Tons

6 Allied Hospital, Faisalabad 120 Tons

7 Holy Family Hospital,

Rawalpindi 94.50 Tons

8 Attock Refinery Hospital,

Rawalpindi 75 Tons

9 Fatima Medical Hospital

Khanewal Road, Multan 4.5 Tons

Total 1074 Tons

88

Table 47: Toolkit calculation for mercury releases from medical

waste incineration

No File 11

Output factors Output Kg

No source 159 Type of transfer % Total

No Category 58 air output

distribution factor 1 164.72

Category

name Waste incineration

water output

distribution factor 0 0

Sub category

no 583

land output

distribution factor 0 0

Sub category

name

Incineration of medical

waste

Product output

distribution factor 0 0

Phase 1 0 waste output

distribution factor 0 0

Phase 2 0 disposal output

distribution factor 0 0

Phase 3 0 Total 164.72

Output

scenario

No emission reduction

devices Mass balance 0

Exist Yes

Input factor

by default 8-40

g Hg/t waste

incinerated

Input factor x 1000

Activity rate 4118 T/Year

Hg input 40 g Hg/t waste

incinerated

Hg input

calculation 164.72 Kg/year

89

4.4.9 Waste deposition/land filling and waste water treatment

This category refers to any waste that is sent for disposal to landfills or backyards.

As indicated in the UNEP’s Toolkit, there are five types of waste deposition and waste

water treatment sub-categories addressed including, controlled landfills/deposit, diffuse

deposition under some control, informal local disposal of industrial production waste,

informal dumping of general waste, and waste water treatment. In this regards and based

on Pakistan context, the waste disposal in Pakistan can be discussed in three types: (1)

controlled landfills; (2) informal waste disposal and (3) waste water treatment .The detail

of these three types in Pakistan is given below;

4.4.9.1. Controlled landfills sites

There are two controlled landfills sites in Karachi. Each one has an area of about

500 acres. One site is located at Jam Chakro, Sirjani, North Karachi and the other site at

Gondal Pass, Hub River road, Karachi. There is one controlled landfill site of 14 acre at

Kasur Tannery Waste Management Agency (KTWMA), Kasur. Total quantity of wastes in

controlled land filling in the country was 1,900,000 tons per year.

90

Table 48: Toolkit calculation for mercury releases from controlled

landfills/deposits

No File 12

Output factors Output Kg

No source 165 Type of transfer % Total

No Category 59 air output distribution

factor 0 0

Category name

Waste

deposition/landfilling

and waste water

treatment

water output

distribution factor 0.1 190

Sub category

no 591

land output

distribution factor 0.9 1710

Sub category

name

Controlled

landfills/deposits

Product output

distribution factor 0 0

Phase 1 0 waste output

distribution factor 0 0.00

Phase 2 0 disposal output

distribution factor 0 0

Phase 3 0 Total 1900

Output

scenario (a Mass balance 0

Exist Yes

Input factor by

default 1-10 g Hg/t waste

Input factor x 1000

Activity rate 1900000 T/Year

Hg input 1 g Hg/t waste

Hg input

calculation 1900 Kg/year

91

4.4.9.2. Informal waste disposal

The solid waste is dumped at various locations in the cities. This waste is burnt by

respective people/sanitary workers. The quantity of informal waste disposal was 255 000

tons per year in the country.

Table 49: Toolkit calculation for mercury releases from informal

dumping of general waste

No File 14

Output factors output

No source 168 Type of transfer % Total Kg

No Category 59

air output

distribution

factor

0.0005 1.275

Category name

Waste deposition/land

filling and waste water

treatment

water output

distribution

factor

0.4995 1273.725

Sub category no 594

land output

distribution

factor

0.5 1275

Sub category

name

Informal dumping of

general waste

Product output

distribution

factor

0 0

Phase 1 0

waste output

distribution

factor

0 0.00

Phase 2 0

disposal output

distribution

factor

0 0

Phase 3 0 Total 2550

Output scenario 0 Mass balance 0

Exist Yes

Input factor by

default 1-10 g Hg/t waste

Input factor x 1000

Activity rate 255,

000 T/Year

Hg input 10 g Hg/t waste

Hg input

calculation 2550 Kg/year

92

4.4.9.3. Waste water treatment

The total quantity of waste water treatment is 93,776,721 m3 per year. However, the

average concentration evaluated from mercury analysis was 2 mg/ m3 of water.

Table 50: Toolkit calculation for mercury releases from waste water

treatment

No File 13 Output factors output

No source 169 Type of transfer % Total Kg

No Category 59 air output

distribution factor 0 0

Category name

Waste

deposition/landfilling and

waste water treatment

water output

distribution

factor

1 187.553448

Sub category no 595 land output

distribution factor 0 0

Sub category

name

Waste water

system/treatment

Product output

distribution factor 0 0

Phase 1 0 waste output

distribution factor 0 0

Phase 2 0 disposal output

distribution factor 0 0

Phase 3 0 Total 187.553

Output scenario No treatment; direct

release from sewage pipe Mass balance 0

Exist Yes

Input factor by

default 0.5-10

mg Hg/m3

waste water

Input factor x 1000000

Activity rate 93776724 m3/year

Hg input 2 mg Hg/m

3

waste water

Hg input

calculation 187.553448 Kg/year

93

4.4.10 Crematoria and cemeteries

This category refers to crematoria and cemeteries. The practice of burning dead

bodies is not practiced in Pakistan.

4.4.11 Identification of potential hot-spots

The potential hot-spots of mercury release identified by the UNEP’s Toolkit refer

to post or abandoned sites of chemical production, pulp and paper manufacturing,

chlor-alkali production, etc. which are classified as follows:

Sites of closed/abandoned chlor-alkali production.

Other sites of production of former chemical where mercury compounds were

produced (pesticides, biocides, pigments etc.), or mercury/compounds as catalysts

were used (VCM/PVC etc.).

Sites of closed pulp and paper manufacturing (with internal chlor-alkali production

or former use of mercury-based slimicides).

Sites of closed production for manufacturing of switches, batteries, thermometers,

other products.

Deposits of tailings/residue from mercury mining.

Deposits of tailings/residue from other non-ferrous extraction of metal.

Deposits of tailings/residue from small and large scale mining of gold.

Dredging of sediments.

Sites of relevant accidents.

Sites of discarded district heating controls (and other fluid controls) where mercury

pressure valves are used.

In Pakistan, there are two abandoned chlor alkali plants with mercury cell

technology and can be considered as potential hot-spots of mercury release.

94

4.5. OVERVIEW OF THE MERCURY INVENTORY

RESULTS

Pakistan has a different and complex situation regarding the collection of exact data

about the use and release of mercury compared to developed countries and some

developing countries. However, the data of Pakistan is based on estimation due to

non-availability of proper inventory of mercury and mercury containing products.

Table 51: Summary of mercury release from all categories

No Category and

Sub-category Activity rate Input factor Amount (Kg Hg/y)

Min Max Min Max

1 Extraction and use of fuel/energy sources

1.1 Coal combustion in

large power plants 2091310 T/y

0.05 g

Hg/T

0.5 g

Hg/T

104.5655

Kg/year

1045.655

Kg/year

1.2-a

Mineral oils -

extraction, refining

and use

1610762 T/y

0.01

mg

Hg/T

0.01

mg

Hg/T

0.01610762

Kg/year

0.016107

62

Kg/year

1.2-b

Use of gasoline,

diesel and

distillates

567182.5 T/y 1 mg

Hg/T

100

mg

Hg/T

5.676182

Kg/year

567.6182

Kg/year

1.2-c

Natural gas -

extraction, refining

and use

29540000000

m3/year

0.03 μ

gHg/N

m3 gas

0.4 μg

Hg/Nm3 gas

0.8862

kg/year

11.816

kg/year

2 Production of other minerals and materials with mercury impurities

2.1 Cement production 25000000 T/y 0.02

g Hg/T

0.1

g Hg/T 500Kg/year

2500Kg/

year

3 Intentional use of mercury in industrial processes

3.1

Chlor-alkali

production with

mercury-Technolo

gy

52800 T/y 25

g Hg/T

400

g Hg/T 1320 Kg/year

21120

Kg/year

4 Consumer products with intentional use of mercury

4.1 Thermometers with

mercury

310.365

items/y

0.5

items/y

1.5

items/y

155.1825

Kg/year

465.5475

Kg/year

4.2-a

Light sources with

mercury(fluorescen

t tube)

5613180

items/year

10 mg

Hg/item

10 mg

Hg/ite

m

56.1318

Kg/year

56.1318

Kg/year

4.2-b Light sources with

mercury(metal

360866

items/year

25 mg

Hg/item

25 mg

Hg/ite

9.02165

Kg/year

9.02165

Kg/year

95

No Category and

Sub-category Activity rate Input factor Amount (Kg Hg/y)

Min Max Min Max

halide lamps) m

4.3-a

Batteries with

mercury (alkaline,

other than button

cell shapes)

1573 T/year 0.25 kg

Hg/T

0.25 kg

Hg/T

393.25

Kg/year

393.25

Kg/year

4.3-b

Batteries with

mercury {mercury

oxide (all sizes)}

also called

mercury-zinc cell}

0.462 t/year 320

kg/T

320

kg/T

147.84

Kg/year

147.84

Kg/year

5 Other intentional products/process uses

5.1

Misc. Product uses,

mercury metal

uses, and other

sources

5779 T/year 1 kg

Hg/T

1 kg

Hg/T

5779

Kg/year

5779

Kg/year

6 Waste incineration

6.1 Incineration of

medical waste 4118 T/year

8 g

Hg/T

40 g

Hg/T

32.944

Kg/year

164.72

Kg/year

7 Waste deposition/land filling and waste water treatment

7.1 Informal dumping

of general waste 255000 T/year 1 g Hg/T

10 g

Hg/T

255

Kg/year

2550

Kg/year

7.2 Control

landfills/deposits

1900000

T/year 1 g Hg/T 1 g Hg/t

1900

Kg/year

1900

Kg/year

7.3 Waste water

treatment

93776724

m3/year

2 mg

Hg/m3

2 mg

Hg/m3

187.5534

48

Kg/year

187.553448

Kg/year

TOTAL 10846

Kg/year

36898.77

Kg/year

96

Table 52: Type of mercury release per category

Sub

category no Sub category name air water land product waste

511 Coal combustion in large power plants x

513 Mineral oils - extraction, refining and use x

514 Natural gas - extraction, refining and use x

531 Cement production x

541 Chlor-alkali production with mercury-technology x

551 Thermometers with mercury x x x

553 Light sources with mercury x x x

554 Batteries with mercury x x x

565 Miscellaneous product uses, mercury metal uses,

and other sources x x x

583 Incineration of medical waste x

591 Controlled landfills/deposits x x

594 Informal dumping of general waste x x x

595 Waste water system/treatment x

Fig. 5: Mercury input in environment

0 5,000 10,000 15,000 20,000 25,000

Chlor-alkali production with…

Informal dumping of general…

Controlled landfills/deposits (a

Mineral oils - extraction,…

Batteries with mercury

Incineration of medical waste

Light sources with mercury

Light sources with mercury

Hg input calculation

Hg input calculation

97

Fig.6: Total mercury releases in air (Kg per year)

Fig.7: Mercury releases in water (Kg per year)

0 500 1000 1500 2000 2500 3000

Chlor-alkali production with mercury-…

Natural gas - extraction, refining and use

Mineral oils - extraction, refining and use

Cement production (a

Light sources with mercury

Batteries with mercury

Thermometers with mercury

Controlled landfills/deposits (a

air

air

0 500 1000 1500 2000 2500

Chlor-alkali production with mercury-…

Natural gas - extraction, refining and use

Mineral oils - extraction, refining and use

Cement production (a

Light sources with mercury

Batteries with mercury

Thermometers with mercury

Controlled landfills/deposits (a

water

water

98

Fig.8: Mercury releases in land (Kg per year)

Figure 5 shows that mercury input to environment from chlor-alkali production is

more than 20,000 Kg. The informal dumping of general waste is more than 5000 Kg.

However, the other categories like controlled landfills, mineral oils, batteries with mercury

ranges from 0 to 5000 Kg.

Figure 6 shows that mercury releases from cement production to air is 2500 Kg.

The mercury releases to air from controlled landfills /deposits is more than 1000 Kg. The

others categories like thermometer with mercury, batteries with mercury, natural gas

ranges from 0 to 1000 Kg.

Figures 7 shows that mercury releases from informal dumping of general waste and

controlled landfills/deposits to water ranges from 1000 to 2500 Kg. The other categories

like thermometer with mercury, light sources with mercury releases mercury to water

ranges from 0 to 500 Kg.

Figure 8 shows that mercury releases in land from informal dumping of general

waste and controlled landfills ranges from 1500 to 2500 Kg. The other categories like

thermometer with mercury, light sources with mercury releases mercury to water ranges

from 500 to 1000 Kg.

0 500 1000 1500 2000 2500

Chlor-alkali production with mercury-…

Natural gas - extraction, refining and use

Mineral oils - extraction, refining and use

Cement production (a

Light sources with mercury

Batteries with mercury

Thermometers with mercury

Controlled landfills/deposits (a

land

land

99

Table 50 shows that mercury releases to air from coal combustion in large power

plants, mineral oils - extraction, refining and use, natural gas - extraction, refining and use,

cement production, thermometers with mercury, light sources with mercury, batteries with

mercury, miscellaneous product uses, mercury metal uses, and other sources, incineration

of medical waste and informal dumping of general waste.

Mercury releases to water from thermometers with mercury, light sources with

mercury, batteries with mercury, miscellaneous product uses, mercury metal uses, and

other sources, controlled landfills/deposits, waste water system/treatment and informal

dumping of general waste.

Mercury releases to land from thermometers with mercury, light sources with

mercury, batteries with mercury, miscellaneous product uses, mercury metal uses and other

sources, controlled landfills/deposits and informal dumping of general waste. Mercury

releases from chlor-alkali production with mercury-technology as waste.

Fig 9: Regional mercury consumption (2005)

Specific (per capita) regional mercury consumption* (2005)

0.00 0.20 0.40 0.60 0.80 1.00 1.20

East & Southeast Asia

South Asia

European Union (25 countries)

CIS & other European countries

Middle Eastern States

North Africa

Sub-Saharan Africa

North America

Central America & the Caribbean

South America

Australia, New Zealand & Oceania

Grams of mercury per capita*Gross mercury consumption, i.e., before recycling, etc.

100

Comparison of Inventory results with world Hg consumption

Average per capita Hg use per year in South Asia: 0.12g

Population of Pakistan: 173000000 habitats

Estimated Hg use in Pakistan per year: 20,760 Kg

Average value between Min and Max inputs: 23870 kg

4.6. OVERALL CONCLUSION

It was observed that most of the waste water and solid samples collected from all

the four provinces of the country, show mercury contamination although the results are

lower than the NEQS limits but only marginally. It also reflects that all the sectors of

society and industry have exposure to mercury. This study was focused only on limited

industries as well as industrial and sewerage effluents and solid waste sites.

The maximum mercury concentration was found at the solid waste disposal sites in

all areas of provinces of Pakistan. These high results are due to the dumping of mercury

and its compounds in municipal and industrial waste without prior segregation. However,

this value of mercury is dangerous for humans as well as a disaster for aquatic life. The

proper disposal or removal of mercury from the solid waste could be reliable mitigation

measure for the toxicity of mercury.

It is for the first time in the history of Pakistan that a preliminary study on the

vulnerable issue of the use and release of mercury in the country has been carried out for its

use as a key document for nationally sound management of mercury release. To achieve

the goal of reporting in this area, the responsible stakeholders of concerned ministries, their

line agencies and local authorities conducted survey on mercury use and release sources in

all the four provinces of Pakistan.

While carrying out the survey at the concerned ministries, provincial departments,

local authorities etc. and various sites, many problems were faced regarding critical gaps in

making and keeping statistical records, such as lack of reliable data and information from

various generating/releasing sources. In this regard, most data/information was obtained by

101

estimations made by local line institutions and as a result, some difficulty in calculating

actual levels of the release of mercury into the environment. Despite these challenges, the

survey activities have sensitized the stakeholders on mercury issues and related harmful

effects to human health and the ecosystem. Nevertheless, a concerted effort was made in

obtaining and calculating the release of quantity of mercury into the environment and it is

concluded that the total quantity of mercury in Pakistan is:

Maximum emission and transfer: 36898 Kg per year

Minimum emission and transfer: 10842 Kg per year

This study is the first step which would prove a milestone towards conducting a

full-fledged survey covering all the sectors in due course of time. To develop such kind of

full inventory, it will be required to assemble all information data from many sectors/fields

which are specified in categories that are addressed in the Toolkit of UNEP, which reflects

Pakistan’s context.

This mercury inventory will assist the decision makers of the country in the sound

management of mercury leading to the provision of benefits for not only the existing

generation but also the future generations.

102

CHAPTER 5

CONCLUSIONS AND RECOMMENDATIONS

5.1. CONCLUSIONS

It was observed that most of the waste water and solid waste of municipal and

industrial waste samples collected from all the four provinces of the country, show

mercury contamination. Although, the results are lower than the NEQS limits but only

marginally. It also reflects that all the sectors of society and industry have exposure to

mercury. This study was focused only on limited industries as well as industrial, sewerage

effluents, municipal and industrial waste sites.

The maximum mercury concentration was found at the solid waste disposal sites in

all areas of provinces of Pakistan. These high results are due to the dumping of mercury

and its compounds in municipal and industrial waste without prior segregation. However,

this value of mercury is dangerous for humans as well as a disaster for aquatic life. The

proper disposal of mercury and removal of mercury bearing products from the solid waste

streams could be reliable mitigation measure for the toxicity of mercury.

In human hair samples of the group exposed to mercury, the value of mercury

exceeds normal values (2.0 µg/g) recommended by the WHO (1990).This can be related to

prolonged exposure of workers to the mercury vapour. Apparently, the longer is the

duration of exposure, the higher is the value of total mercury (T-Hg) found in their hair

samples. For example, the workers of chlor-alkali sector come into contact with mercury

and mercury vapour at the work place (Ittehad Chemicals Limited, Kala Shah Kaku

employing chlor-alkali process using mercury cell technology) thus resulting in high

concentration of T-Hg in their hair samples.

The workers of the chlor-alkali factory (Sittara Chemicals Industries Limited,

Faisalabad) who have completely phased out Mercury cell technology, the high

concentration of T-Hg in hair samples could be due to exposure to the contaminated areas.

High value of mercury could be due to exposure in earlier period when Sittara Chemicals

103

were using mercury cell. Although, the personnel in dental amalgam sector (Punjab

Dental College and Hospital, Lahore) have been exposed to mercury usage, yet mercury

level is within WHO limits, owing to better occupational practices and proper knowledge.

However, in the control group, lower concentration of total mercury in hair samples was

recorded as a result of limited exposure to mercury involving students and staff at Punjab

University, Lahore.

It is for the first time in the history of Pakistan that a preliminary study on the

vulnerable issue of the use and release of mercury in the country has been carried out for its

use as a key data for nationally sound management of mercury release. To achieve the goal

of reporting in this area, the responsible stakeholders of concerned ministries, their line

agencies and local authorities conducted survey on mercury use and release sources in all

the four provinces of Pakistan.

While carrying out the survey at the concerned ministries, provincial departments,

local authorities etc. and various sites, many problems were faced regarding critical gaps in

making and keeping statistical records, such as lack of reliable data and information from

various generating/releasing sources. In this regard, most data/information was obtained by

estimations made by local line institutions and as a result, some difficulty in calculating

actual levels of the release of mercury into the environment. Despite these challenges, the

survey activities have sensitized the stakeholders on mercury issues and related harmful

effects to human health and the ecosystem. Nevertheless, concerted efforts were made in

obtaining and calculating the release of the quantity of mercury into the environment and

concluded that the total quantity of mercury in Pakistan is;

Maximum emission and transfer: 36898 Kg per year

Minimum emission and transfer: 10842 Kg per year

This study is the first step which may prove a milestone towards conducting a

full-fledged survey covering all the sectors in due course of time. For such a full inventory,

it will be necessary to collect all information from various sectors/fields as specified in

categories and sub-categories addressing in the UNEP’s Toolkit, which reflects Pakistan’s

context.

104

This mercury inventory will assist the decision makers of the country for the

sound management of mercury leading to the provision of benefits for not only the existing

generation but also the future generations.

5.2. RECOMMENDATIONS

The overall aim of this study was to identify and quantify mercury releases in

Pakistan. On the basis of results and discussion of this study, it is possible to make some

recommendations for mercury waste management in Pakistan. This mercury waste

management will improve the quality of life of people and conserve aquatic resources by

reducing mercury releases to environment through ensuring provision for mercury

alternatives at all levels at an affordable cost and in an equitable, efficient and sustainable

manner. The main recommendations are;

1. Conduct more studies to identify and quantify mercury from all sources.

2. Coordinate with advanced research laboratories to study the health impacts of

mercury

3. Conduct a detailed study for the remediation of mercury exposed people.

4. Conduct a study for the determination of mercury during coal combustion.

5. Conduct a study on the environmental impacts of mercury products during final

disposal

6. Replace mercury products with mercury alternatives in future.

7. Conduct a study for most economical and environmental friendly mercury

alternatives.

8. Conduct a study for the recovery/recycling of mercury from mercury waste and

mercury products.

9. Conduct a study on the determination of methyl mercury in rivers and sea.

10. Conduct a study on the determination of methyl mercury in all types of fish.

11. Conduct a study on the health impacts of methyl mercury on human beings.

12. Ensure protection and safety of all people working/using mercury for different

purposes.

13. Encourage community participation and empowerment in planning, implementation,

monitoring and operation for safe disposal of mercury.

105

14. Promote cost effective and appropriate technological options for proper handling

of mercury.

15. Increase public awareness about mercury releases, their toxicity and proper disposal

through media and formal education.

16. Promote public-private partnership for enhancing access to Environmentally Sound

Management system for mercury disposal.

17. Application of Basel Convention technical guidelines on mercury use sectors like

chlor-alkali industry, health sector (especially dental amalgams) and light sources

sector.

18. Upgrade and revise the current legislation in the context of mercury pollution.

19. Encourage NGOs and individual researchers to identify mercury hazards and

entertain their suggestions.

20. Mercury containing devices must be kept out of the municipal waste stream during

the incineration and land filling.

21. Mercury containing batteries should be handled with care.

22. Waste reduction and proper waste management of products containing mercury

should be considered in households, business, industry and mercury spills.

23. In order to regulate mercury at consumer level, all purchasers of mercury containing

products should be registered and proper mercury/chemical regulation unit should be

established in all provincial EPA’s.

24. Replacement of mercury products with mercury alternatives must begin at the

production level in industrial processes and also for making of products for direct use

by consumers.

25. Disposal of dry mercury cells of all types having high concentration of mercury

should be high priority. In addition, pressure measuring devices, new and old (come

with scrap e.g. ship breaking) should be carefully managed.

26. Mercury poisoning should be included in environmental awareness campaigns. It

should be a part of pollution plus poisoning campaigns.

The recommendations for mercury waste management in chlor-alkali industry,

health and light products sectors at national level are given in Appendix-4.

106

CHAPTER 6

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