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NUCLEAR ENERGY AND HEALTH RISKS. A QUEBEC PERSPECTIVE ÉRIC NOTEBAERT MD, MSc President, HPGS ( Quebec Chapter of PGS ) Associate Professor of Medicine, University of Montreal September 26th, 2009. PLAN. 1. Risks for the general population 2. Mechanisms and models used
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NUCLEAR ENERGY AND HEALTH RISKS A QUEBEC PERSPECTIVE ÉRIC NOTEBAERT MD, MSc President, HPGS ( Quebec Chapter of PGS ) Associate Professor of Medicine, University of Montreal September 26th, 2009
PLAN • 1. Risks for the general population • 2. Mechanisms and models used • 3. The CANDU and the tritium problem • 4. Six canadian studies • 6. What is going on in Quebec ? • 7. Conclusions
RISKS FOR THE GENERAL POPULATION • Three major recent publications • Baker P.J. et Hoel D.G.: Meta-analysis 2007 136 sites, 8 countries. • Mangano J. et Sherman J.D.:Meta-analysis 2008 51 sites, USA 67 Counties. • Kaatsch P., Spix C., Jung I. et Blettner M. 2008 16 sites, Germany, KiKK study. Case-Control study.
Meta-analysis No. 1 :Baker PJ • CHILDHOOD LEUKEMIAS • 136 Nuclear power plants, uranium mines, reprocessing sites, weapons sites. • 17studiesgrouped together. • 8 Countries: UK, Germany, Canada, Scotland, Spain, USA, France and Japan. • Majority of the studies: Increased incidence, but not statistically significant.
Meta-analysis No. 1: Baker PJ European Journal of Cancer Care 2007:16:355-363
Meta-analysis No 1: Baker PJ Fixed effects: Biggest studies have a biggest influence on the results. Random effects: More appropriate if important heterogeneity ( as here ).
Meta-analysis No. 1: Baker PJ • CONCLUSIONS: • No publication bias. • Incidence: Fixed and random effect: Meta-SIR all ≥ 1. Statistically significant. • Marked increase in the 0-9 y.o. group. • Death risk mainly increased in the 0-9 y.o. group < 16 km. • Association ≠ Cause→effect.
Meta-analysis No.2: Mangano. • CHILD LEUKEMIA DEATH RATES • 51 US Nuclear reactors • 67 Counties • Population : 25 000 000. • Divided in 3: • Nuclear plants that started 1957-1970 (oldest) • Nuclear plants that started 1971 – 1981 (newest) • Nuclear plants started in 1957-1981, and shut down. European Journal of Cancer Care 2008;17:416-418
Meta-analysis No. 2: Mangano • CONCLUSIONS: Mortality: • ↑ 13.9% Mortality near older plants 57-70 • ↑ 9.4% Mortality near newer plants 71-81 • ↓ 5.5% Mortality near plants started in 57-81 and later shut down • Total 1292 deaths. • Statistically significatif.
Meta-analyse No. 2: Mangano • CONCLUSIONS. • Radiation effect more severe among babies, children than adults. • Biggest plant has the highest incidence ↑: +29.5% • Association ≠ causality. • Bias are possible: Other pollutants ? Demographic differences ( poverty – proximity to medical facilities )? • Global context in the USA: Evolution from 1975 to 2004: ↑ Incidence of leukemias 28.7% ↓ Mortality of 49.0%
Study No. 3: KiKK • CHILDHOOD LEUKEMIAS • 16 Nuclear power plants • Germany. • Case-control study. • 593 cases / 1766 controls. • Government-sponsored and results accepted by the Govt. Deutsches Arzteblatt International 2008;105(42):725-732
Study No. 3: KiKK • CONCLUSIONS: • Risks are clearly linked to proximity to nuclear reactors. • Statistically significatif, at ≤ 5 km. • Risks appear to extend as far as 70 km to the nuclear reactors. • Association ≠ causality.
2. MECHANISMS AND MODELS USED BEIR VII: 2006
2. MECHANISMS AND MODELS • BEIR VII: • USA: National Academy of Sciences. • Committee to Assess Health Risks from Exposure to Low Levels of Ionizing Radiation. • Effects on health of LET: low linear energy transfer • Most comprehensive study done to date on this subject. http://www.nap.edu/catalog/11340.html
2. MÉCANISMES ET MODÈLES • Average annual radiation on a population: 2.4 mSv/year:
2. MÉCANISMES ET MODÈLES • Low dose: ≤ 100mSv • CT-scan ( abdomen )= 10-15 mSv • Limit for workers: 50 mSv/y. • Different hypothesis concerning low dose radiation: Risk =or ↓ (hormesis effect) or ↑. • In utero radiation: Risk of cancer ↑ if mother receives a dose ≥ 10 mSv * 100 mSv ≈ 100 Gy ≈ 10 rad ≈ 10 REM
2. MECHANISMS AND MODELS • More appropriate model: ‘Linear No-Threshold’ (LNT). • Risk is a function of age and sex. • There is no thresholdunder which we can say for sure that there is no risk. • 10 mSv → 1/1000 develop cancer. • Other possible risks: ↑ Atherosclerosis – CAD – Stroke – Immunomodulation – Liver diseases – etc But very few data yet.
2. MECHANISMS AND MODELS • Other publications, other estimates: • Traumatology (‘full body scan’): If ≥ 100mSv: 1/1000 death by thyroid cancer. • Dose 100 mSv: risk of death by cancer: • Baby: 1/100 • Young adult: 1/200 • Adult: 1/1000 ( or 10mSv ≈ 1/10 000 ) • Scan abdo-pelvic: 10-20 mSv: Risk of death: • Baby: 1/1000 • Teenager: 1/2000 • Adult: 1/10 000 AJR:176.Feb 2001 Brenner DJ. Radiology 2004:232. Crit Care Med 2009;37:1336 Brenner DJ. NEJM 2007;357:2277
3. CANDU AND TRITIUM • CHARACTERISTICS: • Radioactive isotope of hydrogen: 3H. • β emitter short distance. • Generally under the form: tritiated water: 3HOH • Internal emitter: Inhaled / Swallowed. • Biggest emmiter: Candu, Sellafield, La Hague. The hazards of tritium – revisited. Ian Fairlie Medicine, Conflict and Survival.2008;24(4):306
3. CANDU AND TRITIUM • ‘THE MISUNDERSTOOD NUCLIDE’ • Weak nuclide as β particle has low energy. • But radiobiological effect (RBE) ↑: Low range penetration → cell damage ↑↑. • 3H quickly incorporated in proteins, lipids, and DNA. → ‘OBT’ ( organically bound ) • 3H RBE = 2 or 3, and not 1.
3. CANDU AND TRITIUM • BEIR VII: • Tritium: Easily fixed on DNA • More fragile cells: Rapid development → organogenesis; genetic material. • Possible results: Spontaneous abortions, sterility, congenital anomalies, hypothyroidism, cancers.
3. CANDU AND TRITIUM • CERRIE REPORT: 2003. • Committee formed UK Government. • Internal emitter ‘by excellence’ • Suggested: dose coefficient ↑ 10-15 for HTO ( tritiated water ) • Suggested: dose coefficient ↑ by 5 pour OBT ( organically bound tritium ) CEERIE: Committee Examining Radiation Risks of Internal Emitters. 9th meeting. London.
3. CANDU AND TRITIUM • AGIR REPORT: 2007 • Committee formed by UK Gouvernment • Most comprehensive study on 3H. • RBE between 1.5-3.0. Average = 2.5 • US EPA has adopted 2.5 • AGIR suggests that ICRP ( International Commission on Radiological Protection ) should review its recommendations ( that are more conservative ).
3. CANDU AND TRITIUM • OFFICIAL ACCEPTABLE LIMITS: • Canada-Quebec: 7000 Bq/L • USA: 740 Bq/L • Europe: 100 Bq/L • Objective California: 18 Bq/L
3. CANDU AND TRITIUM • BAPE REPPORT - March 2005 • ‘Canal de rejet’: 420 Bq/L • Surface water, winter: 60 000 Bq/L • Underwater: 20 000 Bq/L • ‘Eau de résurgence’: 1 000 Bq/L • Air: 0.23-1.17 Bq/m3 ( N: 0.05 Bq/m3 ) • Milk: Some data 30 Bq/L ( N: 5 Bq/L )
4. SIX CANADIAN STUDIES • LIMITS OF EXISTING STUDIES • 1. RCT: ‘gold-standard’. Obviously none. • 2. COHORT STUDIES. Confounding factors/ Needs a huge population. • 3. CASE-CONTROL STUDIES: Bias ( memory, etc… ) • 4. ECOLOGIC STUDIES Can show a relationship. No cause / effect.
4. SIX CANADIAN STUDIES • 3 OTHER IMPORTANTS POINTS: • ‘Healthy worker effect’ • Statistically significant. If ‘n’ too small: Even if not statistically significant, may be important. • Clinically significant. Deadly disease: Even if small number, may be important.
4. SIX CANADIAN STUDIES • 1. CHILDHOOD LEUKEMIA AROUND CANADIAN NUCLEAR FACILITIES 1 & 2. Clarke et al 1989 – 1991 • Funded by Canada Atomic Energy Ltd. • Ecologic study. • Radius: 25km from Ontario Power Plants. • ‘n’ small. • Phase 1: 0-4 y.o. / Phase 2: Ad 14 y.o.. • Phase 2: ↑ incidence leukemias, but not statistically significant • CRITIQUE: small ‘N’, large radius.
4. SIX CANADIAN STUDIES • 2. OCCUPATIONAL EXPOSURE OF FATHERS TO IONIZING RADIATION AND THE RISK OF LEUKEMIA IN OFFSPRING – A CASE-CONTROL STUDY. McLaughlin et al. 1992. • 112 children with cancer and 890 controls. • Children living near a nuclear plant 1950-1988 • ‘Total body’ exposure, tritium, radon and radon ‘progeny’. • ↑ Incidence of leukemia, mostly among children of fathers working in uranium mines. Not statistically significant ( small ‘n’ ).
4. SIX CANADIAN STUDIES • 3. TRITIUM RELEASES FROM THE PICKERING NUCLEAR GENERATING STATION AND BIRTH DEFECTS AND INFANT MORTALITY IN NEARBY COMMUNITIES 1971-1988. Johnson & Rouleau 1991. • Ecological study. Congenital malformations, neonatal mortality, spontaneous abortions. • 25 km from Pickering • ↑ Stat. significant: Down Syndrome, correlation with tritium air. • Association: Malformation CNS and tritium air. • Small ‘n’, hence correlations. Nothing is statistically significant.
4. SIX CANADIAN STUDIES • 4. RISK OF CONGENITAL ANOMALIES IN CHILDERN OF PARENTS OCCUPATIONALLY EXPOSED TO LOW LEVEL IONIZING RADIATION. Green et al. 1997 • Case-control. • Financed by Ontario-Hydro. • Fathers of children born 1979-1986 with congenital anomaly. Vs other fathers. • Father’s radiation dose ? • ↑ Irradiation amongst fathers children with congenital anomaly. • Small ‘n’. Not statistically significant.
4. SIX CANADIAN STUDIES • 5. ANALYSIS OF MORTALITY AMONG CANADIAN NUCLEAR POWER INDUSTRY WORKERS AFTER CHRONIC LOW-DOSE EXPOSURE TO IONIZING RADIATION: Zablotska et al. 2004 • 45 000 workers. • Ontario, Quebec, New Brunswick • 1957-1994 • Leukemia death ↑ function of the received radiation dose • LEUKEMIA: ERR / Sv: 52.5 Statistically significant • SOLID CANCERS : ERR / Sv: 2.8 Almost stat. signif.
4. SIX CANADIAN STUDIES • 5. Zablotska et al study. 2004. F.Up • Table 5:
4. SIX CANADIAN STUDIES • 6. RADIATION AND HEALTH IN DURHAM REGION STUDY. Whitby, Ontario. 2007. • Ecologic. Pickering et Darlington areas. • Impossible to conclude that there is a causal link. • Chromosomic anomalies and cancers • Linked by municipalities, not by real proximity to a nuclear plant. • People who have always been living there, newcomers, people who moved out of the area. • Data started in 1983 ( Pickering opened in 1971 )
4. SIX CANADIAN STUDIES • 6. DURHAM Study 2007. F.Up • RESULTS: • ↑ Statistically significant neural tube defect 81-92 à 03-04. • ↑ Incidence Down. • ↑ Significant leukemia amongst ♂ in Darlington 1993-04. • ↑ Significant cancer thyroid amongst ♂ in Ajax-Pickering. • ↑ Marked incidence of cancers amongst ♀ and ♂ after the opening of Darlington. • ↑ Breat cancers in Ajax-Pickering 1981-92. • ↑ Incidence of multiple myeloma amongst ♀ and ♂ in Durham and Oshawa-Whitby.
CONCLUSIONS - INTERNATIONAL AND CANADIAN STUDIES • Oldest studies: • Methodology poorer. • Small ‘n’. • Tendencies in the majority of studies. • More recent studies: The last 5 years: • Methodology has improved. • Meta-analysis. • Statistically significant results. • Very few Canadian studies – And the Canadian Commission on Nuclear Safety does not plan nor want to do anyone in the future !
5. AND WHAT ABOUT QUEBEC ? • BAPE 2005: • Refurbishment of G-2 does not have to be submited to any environmental assessment ! • Public debate is an absolute necessity • Public Health Department of the Mauricie area: Same position.
5. AND WHAT ABOUT QUEBEC ? • August 2008: Quebec Govt. announces the refurbishment of G-2. • Dozens of environmental groups protest in the medias. • Creation of the Mouvement pour Sortir le Québec du Nucléaire: More that 80 groups join the coalition. • October 2008: Letter HPGS: É Notebaert and 34 physicians: Asking a moratorium on the project and a public debate about G-2.
5. AND WHAT ABOUT QUEBEC ? • January 2009: Canadian Commission on Nuclear Safety Public relations operation in the Bécancour area. • February 2009: Creation of TAP: Tritium Allerte Publique • Marsh 2009: Québec-Sciences: Spécial No. Nuclear energy. • Marsh 2009: Sept-Iles: Citizens are opposed to nuclear mining in the area.
5. AND WHAT ABOUT QUEBEC ? • May 2009: City of Amqui joins the MSQN. • May 2009: HPGS wrote to 1300 physicians regions of G-2 and Sept-Iles • May 2009: Sept-Iles: Forum on uranium • May 2009: Trois-Rivières: People in the streets.
5. AND WHAT ABOUT QUEBEC ? • May 2009: Union des Municipalités du Québec is in favor of the cessation of nuclear energy in quebec. • June 2009: Quebec Govt refuses the long term disposal of nuclear wastes in the province. • June 2009: HPGS asks the CCNS to correct what it publicly declared: That there is no risk to human health ≤100mSv • July 2009: HPGS asks the Quebec Govt to reconsider its standards for acceptable 3H in water ( 7000Bq/L).
5. AND WHAT ABOUT QUEBEC ? • July 2009: Quebec Govt announces that it will review all the Hydro-Quebec ‘STRATEGIC PLAN’ this fall. • September 2009: Campaign launched: Avecenergie.com of the Fondation-Rivières and NatureQuébec: No place for nuclear energy. • October 2009: Conference HPGS - Mouvement Vert Mauricie – Artistes pour la Paix : Pour Un Québec Vert Hors du Nucléaire.
6. CONCLUSIONS • New studies of a better quality and meta-analysis confirm that there are very serious health risks with nuclear energy. • BEIR VII model: LNT widely accepted. There is no such thing as a totally safe level. • Tritium levels in H2O should be immediately lowered to safer standards..
6. CONCLUSIONS • Intergenerational principle of equity. • Many other issues not discussed here: Nuclear wastes; renewable energies to develop; risks of accidents; terrorism; links with nuclear weapons; costs; etc… • Nuclear energy is becoming a ‘hot topic’ now in Quebec. Getting very political. • There is a real possibility of success.