ISCI 3rd International Conference 28th July 2011, University of York

ISCI 3rd International Conference28th July 2011, University of York

Challenges in the analysis of children’s health risks caused by indoor air pollution in developing countries

using and processing data on children’s well-being

Yoko Shimada, 　　 Setsunan University, JapanYuzuru Matsuoka, Kyoto University, Japan

Presentation plan

1. Background

2. Objectives of research

3. Concept of estimation

4. Results of the analysis

5. Summary and outlook for the future

Direct health impacts

Developing countries

Household energy use: mainly relies on combustion of solid fuels

Emission of air pollutants(CO, SO2, NO2, PM etc.)

People are exposed to indoor air pollution

Background (1)WHO “Fuel for Life: Household Energy and Health” p.29

Biomass (wood, animal dung, crop wastes), charcoal, coal

Exposure affects mainly women while cooking, and infants and young children who are usually with their mothers near the cooking area.

UNDP/WHO 2009 report“The Energy Access Situation in Developing Countries, A review Focusing on the Least Developed Countries and Sub-Saharan Africa”

・　 56% of people in developing countries still rely on solid fuels for cooking.　　 3 billion people （ almost half the world’s population)

・ 2 million deaths annually are associated with the indoor burning of solid fuels in unventilated kitchens

　　 44% of these deaths are children. 　　 among adult deaths; 60 % are women

Key Health effects of indoor air pollution・ Childhood Acute Lower Respiratory Infections (ALRI)・ Chronic Obstructive Pulmonary Disease (COPD)・ Lung Cancer

Background (2)

Background (3)

Suggested improvement measures:

・ Improved stoves・ Improved ventilation・ Kitchen design and placement of the stove・ Using clean fuels (kerosene, gas) , or electricity

Recognize and assess the exposure of people to this kind of pollution

Objectives of research

To develop a model to quantitatively analyze indoor air exposure concentration for individual cohorts categorized according to sex, age, occupation status and other factors

To assess the impact of exposure in detail by linking people’s use of time which reflect differences in individual daily life activities

The selected indoor air pollutant:

PM2.5・ Small particles < 2.5 μm in aerodynamic diameter ・ Penetrate deep into the lungs and appear to have the greatest 　 potential to damage health

WHO Air Quality Guideline was set in 2005 Annual mean 10 μg/m3

24 hour mean 25 μg/m3

Concept of estimation

Estimation of Indoor PM2.5 Exposure

aa m m

m

E C T

Daily IndoorPM2.5 exposure concentration (μg/m3) for cohort a:aE

m : Microenvironment

mC : PM2.5 concentration in microenvironment m

a mamT : Time proportion of cohort staying in microenvironment

Cohort classification・ Cohort classification must represent a variety of individuals.

・ Cohorts of children are important to estimate indoor PM2.5 exposure, because PM2.5 exposure affects mainly women, and young children who are with their mothers during cooking and other household activities.

MaleFemale

01 ～ 4

5 ～ 1415 ～ 2425 ～ 3435 ～ 64

65+

WorkingNot working

Gender Age Working status

× × 22 types of cohort

Type of cohort

gender age working condition1 Male 0 -2 Male 1-4 -3 Male 5-14 -4 Male 15-24 Working5 Male 15-24 Not working6 Male 25-34 Working7 Male 25-34 Not working8 Male 35-64 Working9 Male 35-64 Not working10 Male 65+ Working11 Male 65+ Not working12 Female 0 -13 Female 1-4 -14 Female 5-14 -15 Female 15-24 Working16 Female 15-24 Not working17 Female 25-34 Working18 Female 25-34 Not working19 Female 35-64 Working20 Female 35-64 Not working21 Female 65+ Working22 Female 65+ Not working

Typecombination

a


aa m m

m

E C T





“Microenvironment “

A space that has a uniform concentration of pollutants and in which people are present temporarily Interior space of the residence as being made up of a finite number of microenvironments defined by Duan (1982)

Microenvironment indoors at home

m

Microenvironment Purpose Location PM 2.5 source inside residence

Corresponding time spent indoors athome

A Cooking,Eeating

Kitchen,Dining room

Use of cookingburner or hearth

Cooking time + time spent eating indoors at home

B To heat roomsIndoors at homeexcluding kitchenand dining room

Use of fireplace,portable heater etc.

Time spent indoors at home, excludingsleeping time (when outdoor airtemperature is 10 °C or lower)

C To light uprooms

Indoors at homeexcludingbed room

Use of oil orkerosene lamp

Time spent indoors at home during thenight- time excluding sleeping time


aa m m

m

E C T





md

mmm VF

eSC

m

Emission Factor (μg/KJ)

Air Exchange Rate (1/hour)

Removal Rate from indoor air (1/hour)

Volume of Microenvironment (m3)

Fuel Consumption (KJ/hour)

PM2.5 concentration in microenvironment mC

Fuel Consumption for each type of fuel

← International Energy Agency: 　“ World Energy Outlook 2002” “Energy Balances of Non-OECD countries 1960-2005

PM2.5 Emission Factor for each type of fuelEmission

factor (µg/KJ) Source

Firewood 180 Li et al., 2007Charcoal 300 Andreae et al., 2001Crop residue 274 Li et al., 2007Animal dung 429 Reddy et al., 2002

52.4 Ge et al., 2004119 Zhang et al., 2000

0 Fan et al., 2001110 Fan et al., 20012.37 Zhang et al., 20003.07 Zhang et al., 2000

Kerosene (heating)Kerosene (illumination)LPGNatural gas

Type of fuel

Biomas

CoalKerosene (cooking / heating water)

Air exchange rate

← Zhang et al., 1999, Davidson et al. 1986

Removal rate of PM2.5 from indoor← Ozkaynak et al., 1996

Volume of each microenvironment

Household survey data or Census for each country

This is calculated using the data on floor areas, which assumes the height of each microenvironment to be 2 meters.


aa m m

m

E C T





Time Use Survey Data

A (Cooking & Eating)

Corresponding time proportion of each cohort staying in 3 microenvironment

B (Heating)

C (Lighting)

Time allocation of daily activities classified by gender, age, working status

amT

during the day-timeduring the night-time

Time spent indoors not at homeTime spent outdoors

Time allocation for 24 hours

Timespentindoors athome

Sleeping timeCooking timeEating time indoorsOtheractivities

Time Use Survey Data

In almost all countries, the respondents in the time use survey were 15 years of age or over.

Time proportion of each cohort of children (boys and girls aged 0, 1 to 4, and 5 – 14) is set using survey data related to children’s labor, education and daily life

Children’s time use activity categories

Boys/girlsaged 0

Boys/girlsaged 1 - 4

Boys/girlsaged 5 - 14

Sleeping Sleeping ○ ○ ○Satying in kitchen ○ ○ ○Eating ○ ○ ○Other activities at home ○ ○ ○At school ○ ○At home ○ ○Other than at home ○ ○Indoors at home ○ ○Indoors not at home ○ ○Outdoors ○ ○Economic activities: outdoors ○Economic activities: indoorsother than at home ○

At home ○

Cohorts

Eating andother indooractivities

Studying

Playing

Working

Children's time use activity categories

Setting of children’s time spent at home for each activity ・ Staying in kitchen Assumed by referring to the time spent cooking by unemployed

females aged 25 – 34; the mothers with children in each country. ↑　 For children aged 0 and 1 to 4, the daily life activity time for

children in each country is thought to take place in the kitchen, with the children being carried by their mother, and as a result they are thought to be exposed to fuel combustion during cooking.

・ Working time for 0 and 1 - 4 years of age :assumed to be zero for 5 - 14 years of age: set using the data from UNICEF: ” The state of the world’s children 2009”　　 ILO: “Global child labor trends 2000 to 2004” (2006) UCW★ (Understanding Children’s Work): “Child labor survey database”

★ A joint program of the ILO, UNICEF and World Bank

・ Time spent at school set using the data from UNICEF: ” The state of the world’s children 2009” UCW: “Child labor survey database”

・ Sleeping time set using the data from Benesse Co., Ltd. : “Basic Survey on Young Children's Daily Lives and Parents' Childrearing in Five East Asian Cities: Tokyo, Seoul, Beijing, Shanghai, and Taipei.” ・ Time spent in other activities we were unable to obtain data.

Sleeping SleepingSatying in kitchenEatingOther activities at homeAt school / NurseryAt homeOther than at homeIndoors at homeIndoors not at homeOutdoorsEconomic activities: outdoorsEconomic activities: indoorsother than at homeAt home

Playing

Working

Children's time use activity categories

Eating andother indooractivities

Studying

Corresponding time proportion of each cohort of children staying in the 3 microenvironments: A, B and C.

Classification of time proportion of each cohort of children staying in each microenvironment

during the day-timeduring the night-time

Time spentindoors athome

Time spent indoors not at homeTime spent outdoors

Time allocation for 24 hoursSleeping timeCooking timeEating time indoorsOtheractivities

Results of the analysis

Mi croenvi ronmentA (cooki ng +

eati ng)Mi croenvi ronment

B (heati ng)Mi croenvi ronment

C (Li ghti ng) Overal l

Japan 0. 9 1. 7 0. 0 2. 6South Korea 3. 0 29. 3 0. 0 32. 3Chi na 427. 5 444. 2 1. 5 873. 2Tai wan 6. 7 15. 4 0. 0 22. 1Nepal 285. 2 128. 8 1. 4 415. 3Paki stan 178. 2 130. 8 0. 9 310. 0Bhutan 156. 7 115. 5 1. 1 273. 3Indi a 205. 7 8. 5 5. 5 219. 7Bangl adesh 127. 2 0. 0 0. 6 127. 8Indonesi a 171. 9 0. 0 16. 2 188. 1Mal aysi a 39. 9 0. 0 0. 6 40. 6Phi l i ppi nes 107. 8 0. 0 0. 0 107. 8Thai l and 58. 2 0. 3 0. 0 58. 5Cambodi a 155. 0 0. 0 0. 4 155. 4Laos 266. 3 151. 9 0. 9 419. 1

Cohort average dai l y i ndoor PM 2. 5 exposed concentrati on (μ g/ m3)

0 200 400 600 800 1000 1200 1400 1600 1800

Male age 0Male age 1 - 4

Male age 5 - 14Employed male age 15 - 24

Unemployed male age 15 - 24Employed male age 25 - 34


Unemployed male age 35 - 64Employed male age 65 or older

Unemployed male age 65 or olderFemale age 0

Female age 1 - 4Female age 5 - 14

Employed female age 15 - 24Unemployed female age 15 - 24


Employed female age 35 - 64Unemployed female age 35 - 64Employed female age 65 or older

Unemployed female age 65 or older

Average daily exposure concentration μ g/ m（ 3)

Microenvironment A(cooking / eating)Microenvironment B(heating)Microenvironment C(lighting)

Estimated Average Daily Indoor PM 2.5 Exposure Concentration by Cohort in China

0 100 200 300 400 500 600











Unemployed female age 65 or

Average daily exposure concentration μ g/ m（ 3)

Microenvironment A(cooking / eating)Microenvironment B(heating)Microenvironment C(lighting)

Estimated Average Daily Indoor PM 2.5 Exposure Concentration by Cohort in India

Indoor time use of each cohort in China

0 6 12 18 24












hour

Sleeping timeCooking timeThe others

Cooking time of the cohort of unemployed females aged 35 - 64 is the longest

0 6 12 18 24












hour

Sleeping timeCooking timeThe others

Cooking time of the cohort of unemployed females aged 35 - 64 is the longest

Indoor time use of each cohort in India

Summary

Our study enabled detailed assessment of the impact of exposure to PM2.5, because differences in individual daily life activities were reflected in the use of time and linked to an assessment of exposure to indoor air-polluting substances.

However, it will also be important to develop exposure models that take into account the great difference between urban and rural lifestyles in developing countries, as well as the great differences between countries in terms of housing conditions, dietary practices and religious and cultural lifestyles.

For assessment of children’s indoor exposure, it will be necessary to collect more data on children’s time use, child care, education and their mother’s daily activities, which are linked to model parameters.

Yoko Shimada

[email protected]

Thank you

Documents

ISCI 3rd International Conference 28th July 2011, University of York