National Contaminants Program: Canadian Arctic Contaminants Assessment Symposium - Ottawa, March 4-7 2003

The Northern Contaminants Program (NCP) was established in 1991 in response to concerns about human exposure to elevated levels of contaminants in fish and wildlife species that are important to the traditional diets of Northern populations (see Bioaccumulation). Early studies suggested that a wide range of substances including persistent organic pollutants, heavy metals and radionuclides were reaching high levels in the Arctic ecosystem.

The first report released by the NCP, The Canadian Arctic Contaminants Assessment Report - CACAR (1997), focused on the determination of levels, geographic extent, sources of contaminants in the northern atmosphere, environment and its people and the probable duration of the problem. The report provided a greater understanding of the spatial patterns and temporal trends of contaminants in the North. The benefits of the consumption of 'traditional foods' was determined to carry out risk assessments on the human health risks associated with contaminated food.

The second report, CACAR II (2003) provides the results from many different types of studies (ecological, epidemiological etc) focusing on the impacts and risks to human health in the Arctic. Continued measurements and monitoring has been performed on persistent organic pollutants, mercury, cadmium and selenium. The results from several epidemiological studies were reported including studies on the neurobehavioural effects of in utero and lactational exposure to contaminants on children and infant development, risk management strategies to implement dietary changes to reduce intake of contaminated foods and trends (temporal and geographic) in biomonitored animal species (marine birds, mammals -seals, whales, polar bears, fish).

The biological mechanism by which these contaminants impact human health is not yet clear. Recommendations by many researchers suggest cessation of the consumption of certain animals known to be high in mercury in the months preceding conception, during pregnancy and during breastfeeding. As mercury has a relatively short half-life (45 days), total body burden can be significantly reduced prior to conception, thereby minimizing risks to the fetus and nursing infant. Girls and women were recommended to abstain from the consumption of animals known to have high levels of persistent organic pollutants (e.g. PCBs) with very long half-lives, until the completion of childbearing.

These recommendations, and many other risk strategies, attempt to minimize human health risks caused by the consumption of contaminated foods by the implementation of dietary restrictions. The importance of traditional foods to the rich culture and traditions of the Northern peoples was underscored by representatives from the Canadian Arctic at the NCP Symposium. To simply abstain from the consumption of foods such as arctic char, caribou, seal and whale would greatly impact the culture of a people already struggling with the effects of globalization. By working together with Northern populations, the NCP assessment is enhanced by this cooperation. The willingness of the Northern peoples to provide blood and tissue samples, to submit their children to biological sampling and neurobehavioural testing and to provide biological samples from Arctic wildlife obtained by hunting and trapping is a great testimony to the desire of these people to ensure the health of their children and the survival of their culture.