Science of the Total Environment 351–352 (2005) 165–246 www.elsevier.com/locate/scitotenv Review Human health implications of environmental contaminants in Arctic Canada: A review J. Van Oostdam a,*, S.G. Donaldson a,b, M. Feeley c, D. Arnold c, P. Ayotte d, G. Bondy c, L. Chan e,E´ . Dewaily d, C.M. Furgal f, H. Kuhnlein e, E. Loring g, G. Muckle h, E. Myles i, O. Receveur j, B. Tracy k, U. Gill l, S. Kalhok m a Environmental Contaminants Bureau, Safe Environments Program, Health Canada, Rm 4-046, BMO Building, 269 Laurier Avenue W., AL4904B, Ottawa, ON, Canada K1A 0K9 b Carleton University, 1125 Coloney By Drive, Ottawa, ON, Canada K1S 5B6 c Health Canada, Food Directorate, Bureau of Chemical Safety, Banting Research Center, Tunney’s Pasture, Ottawa, ON, Canada K1A 0L2 d Unite´ de recherchen sante´ publique (Centre hospitalier universitaire de Que´bec - Centre hospitalier de l’Universite´ Laval), Universite´ Laval, 945 Ave Wolfe, Ste. Foy, Que´bec, Canada G1V 5B3 e Centre for Indigenous Peoples’ Nutrition and Environment, Macdonald Campus of McGill University, 21,111 Lakeshore Road, Ste.-Anne-de-Bellevue, Quebec, Canada H9X 3V9 f De´partment Science Politique et Unite´ de recherche en sante´ publique (Centre hospitalier universitaire de Que´bec - Centre hospitalier de l’Universite´ Laval), Universite´ Laval, 945 Ave Wolfe, Ste. Foy, Que´bec, Canada G1V 5B3 g Environmental Contaminants Research Division, Inuit Tapiriit Kanatami, 170 Laurier Avenue West, 12th Floor, Ottawa, ON, Canada, K1P 5V5 h E´ cole de psychologie et Unite´ de recherche en sante´ publique (Centre hospitalier universitaire de Que´bec - Centre hospitalier de l’Universite´ Laval), Universite´ Laval, Ste Foy, Que´bec, Canada G1K 7P4 i AXYS Environmental Consulting Ltd., Suite 300, 805 8th Ave SW, Calgary, Alberta, Canada T2P 1H7 j Faculte´ de Medicin, Nutrition, Universite´ de Montreal, CP6128, Succursale Centre Ville Montreal, QC, Canada H3C 3J7 k Health Canada, Environmental Health Directorate, Radiation Protection Bureau, 775 Brookfield Road, AL 6302D1, Ottawa, ON, Canada K1A 0L2 l Health Canada, Health Products and Food Branch, 2nd Floor, Qualicum Twr A, 2936 Baseline, AL 3302C Nepean, ON, Canada K1A 0K9 m Indian and Northern Affairs, Northern Science and Contaminants Research Directorate, 10 Wellington Street, Gatineau, Quebec, Canada K1A 0H4 Accepted 30 March 2005 Available online 16 November 2005 Abstract The objectives of this paper are to: assess the impact of exposure to current levels of environmental contaminants in the Canadian Arctic on human health; identify the data and knowledge gaps that need to be filled by future human health research and monitoring; examine how these issues have changed since our first assessment [Van Oostdam, J., Gilman, A., Dewailly, E´ ., Usher, P., Wheatley, B., Kuhnlein, H. et al., 1999. Human health implications of environmental contaminants in Arctic Canada: * Corresponding author. Tel.: +1 613 941 3570. E-mail address: [email protected] (J. Van Oostdam). 0048-9697/$ - see front matter. Crown Copyright D 2005 Published by Elsevier B.V. All rights reserved. doi:10.1016/j.scitotenv.2005.03.034 166 J. Van Oostdam et al. / Science of the Total Environment 351–352 (2005) 165–246 a review. Sci Total Environ 230, 1–82]. The primary exposure pathway for contaminants for various organochlorines (OCs) and toxic metals is through the traditional northern diet. Exposures tend to be higher in the eastern than the western Canadian Arctic. In recent dietary surveys among five Inuit regions, mean intakes by 20- to 40-year-old adults in Baffin, Kivalliq and Inuvialuit communities exceeded the provisional tolerable daily intakes (pTDIs) for the OCs, chlordane and toxaphene. The most recent findings in NWT and Nunavut indicate that almost half of the blood samples from Inuit mothers exceeded the level of concern value of 5 Ag/L for PCBs, but none exceeded the action level of 100 Ag/L. For Dene/Me´tis and Caucasians of the Northwest Territories exposure to OCs are mostly below this level of concern. Based on the exceedances of the pTDI and of various blood guidelines, mercury and to a lesser extent lead (from the use of lead shot in hunting game) are also concerns among Arctic peoples. The developing foetus is likely to be more sensitive to the effects of OCs and metals than adults, and is the age groups of greatest risk in the Arctic. Studies of infant development in Nunavik have linked deficits in immune function, an increase in childhood respiratory infections and birth weight to prenatal exposure to OCs. Balancing the risks and benefits of a diet of country foods is very difficult. The nutritional benefits of country food and its contribution to the total diet are substantial. Country food contributes significantly more protein, iron and zinc to the diets of consumers than southern/market foods. The increase in obesity, diabetes and cardiovascular disease has been linked to a shift away from a country food diet and a less active lifestyle. These foods are an integral component of good health among Aboriginal peoples. The social, cultural, spiritual, nutritional and economic benefits of these foods must be considered in concert with the risks of exposure to environmental contaminants through their exposure. Consequently, the contamination of country food raises problems which go far beyond the usual confines of public health and cannot be resolved simply by risk-based health advisories or food substitutions alone. All decisions should involve the community and consider many aspects of socio-cultural stability to arrive at a decision that will be the most protective and least detrimental to the communities. Crown Copyright D 2005 Published by Elsevier B.V. All rights reserved. Keywords: Arctic regions; Environmental monitoring; PCBs; Organochlorines; Mercury; Maternal; Infant; Monitoring environmental pollution; Northern populations; Public health; Risk factors; Risk-benefit management Contents 1. Introduction .................................................... 168 1.1. Aboriginal peoples of Canada ....................................... 168 1.2. Aboriginal perspectives on food and health ................................ 170 1.3. Factors that contribute to Aboriginal Northerners’ exposure to country food contamination........ 170 1.4. Evaluation of research in CACAR and application to benefit and risk assessment/management .......................................... 171 1.5. Research ethics ............................................... 172 2. Exposure assessment ............................................... 172 2.1. Country food consumption in the Arctic .................................. 173 2.2. Contaminant levels in people and their relationship to traditional food diets ............... 174 2.2.1. Tissue levels of contaminant results ................................ 175 2.2.2. Levels of mercury in hair and blood ............................... 183 2.2.3. Population groups and studies ................................... 184 2.2.4. Maternal hair ........................................... 185 2.2.5. Maternal/cord blood ........................................ 186 2.2.6. Levels of selenium in maternal blood ............................... 187 2.2.7. Levels of lead in maternal blood ................................. 187 2.2.8. Levels of cadmium in maternal blood ............................... 187 2.2.9. Radionuclide exposure....................................... 187 2.3. Trends in traditional/country food dietary intakes and contaminant exposures ............... 189 3. Toxicology. .................................................... 190 3.1. Priority contaminants ............................................ 190 3.1.1. Toxaphene ............................................. 190 3.1.2. Chlordane ............................................. 192 J. Van Oostdam et al. / Science of the Total Environment 351–352 (2005) 165–246 167 3.2. Toxicological effects induced by exposure to food-chain contaminant mixtures ............. 193 3.2.1. Discussion ............................................ 196 3.3. Contaminant and dietary nutrient interactions ............................... 196 3.3.1. Discussion ............................................ 197 4. Epidemiology and human biomarkers ...................................... 198 4.1. Immune system function.......................................... 199 4.1.1. Clinical outcomes ......................................... 200 4.1.2. Biomarkers ............................................ 201 4.2. Neurodevelopment ............................................. 202 4.2.1. Clinical outcomes ......................................... 202 4.2.2. Biomarkers of developmental effects ............................... 204 4.3. Sex hormone disruption .......................................... 206 4.3.1. Clinical outcomes ......................................... 207 4.3.2. Hormonal biomarkers ....................................... 208 4.4. Oxidative stress .............................................. 208 5. Risk-benefit characterization, assessment and advice ............................... 209 5.1. Contaminant exposure risks ........................................ 210 5.1.1. Contaminant intakes ....................................... 210 5.2. Special considerations for risk management in Arctic communities . .................. 217 5.2.1. Nutritional benefits ........................................ 217 5.3. Social, cultural, spiritual and economic benefits of country food . .................