URANIUM AND RADON:

A PUBLIC HEALTH PERSPECTIVE

Jean-Claude Dessau, mdMSSS

22

UraniumUranium

Heavy metal, radioactive, occurs naturally anywhere on earth

3 natural radio-isotopes : 238U (99,28 %), 235U (0,71 %), 234U (0,0054 %)

Estimated World production: 44 000 Tons/Year

CanadaCurrently the largest producer of uranium in the world (9000 tons of U3O8 in 2008, representing 20% of world production) before Australia and KazakhstanCanada has nearly 10% of global reserve

SaskatchewanThe Canadian company Cameco (subsidiary of Areva), which operates mines that are among the largest in the world. In 2011, the province will have ten operating sitesAthabasca Basin : Uranium content 12%

Nova Scotia and British ColumbiaMoratorium: real potential unknown

QuébecIntense exploration activity and development (no exploitation)

33

Approvals required before opening a uranium mine

Prospecting Licence (MRNF - Ministère des ressources naturelles et de la faune)Environmental Certificate of Authorization for advanced exploration work (excavation and stripping)(MDDEP - Ministère du développement durable, (CNSC-Canadian Nuclear Safety Commission)Obtaining a mining lease (MRNF)Filing a restoration plan and financial guarantees (Investors)Consultation of the Public Health Department (Direction de santé publique-DSP)Assessment and approvals at each stage of the project (CNSC - MDDEP)Mandatory public hearings (BAPE or its equivalent in Federal Territory)

Laws applying to uranium mining projects

Mining Law, Forest Law (MRNF), Law on Environmental Quality, Order 019 on the mining industry (MDDEP) Metal Mining Effluent Regulations (REMM), Health, safety and Security Law (LSST) and Nuclear safety and Control Law (CNSC)

Regulatory Process

44

Uranium in Quebec Uranium in Quebec

Dozens of mining companies to work

Over 200,000 active mining claims covering over 120,000 km2 (7% of Québec)

13% of exploration expenditures ($ 43M invested in over 220 projects)

Pegmatite and uranium vein concentration generally less than 1%

  Ex: Project Matoush (0.34 to 0.89%)

55

Climatic

Economic

Energy

Environmental

Industrial / Technology

Medical (isotopes)

Public health

Societal and ethical

Key Issues

66

Chemical toxicity occurs at much lower doses than the radiological toxicity

This is why the Provincial Norm for drinking water is based on toxicity as inorganic metal (20 µg / L) and not as radionuclide

Mainly due to the ingestion of water rich in uranium

Institut National de Santé Publique du Québec - INSPQ has produced a factsheet on the toxicity of uranium in water.

Toxicological Risk of UraniumToxicological Risk of Uranium

7

Radiological risk of UraniumRadiological risk of Uranium

7

Radiological risk associated with ingestion, inhalation and exposure to external radiation

Risk potentially more important during periods of exploitation The exploration does not pose a risk to health or the environment

Health Hazard Radon and its decay products are historically responsible for high levels of

lung cancer listed among uranium miners

Risk modulated by the concentration, duration of exposure and smoking

Nowadays all mines are well ventilated and lung cancer associated with Radon in mines is not an issue anymore

8

The “Sievert”The “Sievert”

One sievert (Sv) is a very large dose

The effects caused by short-term exposure to very high doses of radiation (acute exposure) vary depending on the dose. Here are some examples:

10 Sv (Sievert) : risk of death within days or weeks;1 Sv : risk of cancer occurring later in life (5 out of 100);0,1 Sv : risk of cancer occurring later in life (5 out of 1000);

Fortunately no one is exposed to such high doses

The « Sievert » is the measure of the effect of radiation on humans

9

The “Sievert”The “Sievert”Even workers who are generally more exposed than the general population are exposed to much lower doses

What are the limits of exposure to radiation?

For Radiation Workers:The Threshold Limit Values (TLVs) published by the ACGIH (American Conference of Governmental Industrial Hygienists) are used in many jurisdictions occupational exposure limits or guidelines: 50 mSv - TLV for the annual dose of radiation workers during any year;20 mSv - TLV for average annual dose for radiation workers, averaged over five yearsThe actual exposure of workers is only one to two mSv per year

(See next slide)

For general public: To the order of a thousandth of a Sievert

1 mSv - Recommended annual dose limit for general public (ICRP - International Commission on Radiological Protection).

1010

Workers Exposure Workers Exposure

11

ConclusionsConclusions

11

Quebec uranium potential is substantial

Perception of uranium industry non-uniform in the population

Uranium mining subject to numerous laws and regulations

There are a lot of information to evaluate the risk of exposure to uranium in the industry

Currently, on average, the uranium miners are exposed to lower levels of radon in the workplace than in their homes

12

Press Review: Protégez-vous, mai 2009Press Review: Protégez-vous, mai 2009

13

Press Review: La facture: 20 octobre 2009Press Review: La facture: 20 octobre 2009

14

Sources of radioactivity for the average Canadian adult Sources of radioactivity for the average Canadian adult

15

QuestionQuestion

What is Radon ?What is Radon ?

16

Physical characteristics of radonPhysical characteristics of radon

Radioactive gasEverywhere on the earth's crustFrom natural uraniumImperceptible by the senses

ColorlessOdorless

Inert (chemically unreactive)

17

Physical characteristics of radonPhysical characteristics of radon

Half-life: 3.8 days

Half a given amount of radon is disintegrated in 3.8 days

Unit of measure: Bq/m3 (Becquerel per cubic meter)

Measurement of radon activity

1 Bq = 1 disintegration per second

18

High Permeability

Low Permeability

Clay

Silt

Sand

gravel

Importance of soil permeability

19

20

Factors influencing the infiltration of radon in homes Factors influencing the infiltration of radon in homes

> 800 Bq/m3

150 à 800 Bq/m3

< 150 Bq/m3

10 000 Bq/m³

18 Bq/m³

Oka

21

INFILTRATION ROUTES

Outdoor concentrations • 0,7 to 35 Bq/m3

• Average: 7 Bq/m3

* Source: Santé Canada

Indoor concentrations • 30 to >2000 Bq/m3 • Average: 45 Bq/m3

Source: Ressources naturelles Canada

22

Effect on health Effect on health

The only known effect of radon is an increased risk of lung cancer

This risk depends on:Concentrationexposure timeSmoking

23

Global Consensus Global Consensus

Radon is a serious public health

2nd leading cause of lung cancer after smoking

First rank among non-smokers

We can not identify a level below which the risk of exposure to radon is nonexistent;

Combined exposure to radon and tobacco:The health effects are greater than the sum of their individual effects.

24

Risk analysis at the provincial level

smokers60%

former smokers

30%

non smokers10%

Othercauses

90%

associated to radon10%

Estimating causes of deathby lung cancer in Quebec

Total: N = 5 436(Statistic Canada 2004)

Deaths associated to radon: N = 540

CigaretteAsbestos

Arsenic

Chrome

Nickel

Atmospheric Pollution

POPULATIONAL RISK

25

Levels of risk associated with radonLevels of risk associated with radon

Lifetime Risk8 h per day

annual average concentration Smoker Non-

smoker

For exposure to 800 Bq/m3 30 % 5 %

For exposure to 200 Bq/m3 17 % 2 %

For exposure to radon at outdoor level (10 Bq/m3) 12 % 1 %

Individual risk(Health Canada)

Measurement Unit : Bq/m3 = Becquerel per cubic meter of air

= Measurement of radon activity

= Number of decays per second per cubic meter of air

26

Measured concentrations in Quebec Measured concentrations in Quebec

Geometric meanin the basement

Geometric meanGround floor

34,6 Bq/m3

(n = 781)

18,0  Bq/m3

(n = 616)

A study in 1992-1993 at the provincial level on 900 homes (Lévesque et al., 1995)

Annual geometric mean concentrations(All areas combined)

27

Estimated exposure of Quebec people

(2008)

Measured concentration(Ground floor)

Estimated number of houses

> 200 Bq/m3 27 000 (1,3%)

> 800 Bq/m3 4 100 (0,2%)

Measured concentrations in Quebec Measured concentrations in Quebec

28

QuestionQuestion

Initiatives about radonInitiatives about radon

29

Health Canada StrategyHealth Canada Strategy

1. Developing policy on radon Lowering the directive 800 to 200 Bq/m3

2. Data collection and advice Federal Buildings in Quebec Measures in 15,000 homes - national study Measurement guides and radon mitigation guide

3. Education and public awareness Workshops, exhibitions, conferences, website and printed documentsQuébec real estate brokers Information campaign for the MRC

30

Canadian Guideline on radon Canadian Guideline on radon

1. Remedial measures should be undertaken in a dwelling whenever the average annual radon concentration exceeds 200 Bq/m³ in the normal occupancy area (where a person can spend more than four hours per day ).

Applies to new and existing buildings

31

Canadian Guideline on radonCanadian Guideline on radon

2. The higher the radon concentration, the sooner remedial measures should be undertaken

radon Concentration(Bq/m3)

Time to take corrective measures

Over 600 In less than a year

Between 200 and 600 In less than 2 years

Less than 200 No action required

Bq/m3 = Becquerel per cubic meter of air

32

Canadian Guideline on radonCanadian Guideline on radon

3. When remedial action is taken, the radon level should be reduced to a value as low as practicable.

4. The construction of new dwellings should employ techniques that will minimize radon entry and will facilitate post-construction radon removal, should this subsequently prove necessary.

33

Radon Measurement Radon Measurement

Measuring time

Radon levels in a building can vary significantly with time

Health Canada recommends a long-term measurement from three to twelve months (preferred)

The ideal time to perform a test of three months is during The ideal time to perform a test of three months is during the heating season which extends from October to April the heating season which extends from October to April

For more information, see the guides at Health Canada:

www.hc-sc.gc.ca/ewh-semt/radiation/radon/index-eng.php

34

Why 3 -12 months? Why 3 -12 months?

Radon levels double / triple between day / night and vary from one week to another, from one season to another .

0

500

1000

1500

2000

2500

3000

3500

10/13 10/20 10/27 11/3 11/10 Date

R a d o n C o n c e n t r a t I o n (Bq/ m3)

35

Radon Measurement Radon Measurement

In general, the cost of a radon test can vary between $ 50 and $ 100

Other measurement methods available which require specialized services of a competent technician (see Health Canada measures Guides)

a b

The types of long term detectorsa) Electret Ion Chamber

b) Alpha-track detector

Corrective Measure Corrective Measure

Active sub-slab depressurization

37

Key messages for citizens Key messages for citizens

Radon is the leading cause of lung cancer among non-smoker, second only to smoking

Measure radon in your home to protect your family. It's simple and cheap

If the level exceeds the guideline, there are solutions: mitigate

38

Thank you !