Traditional knowledge and science reveal southern toxins in northern species

The study investigated the health of Arctic wildlife employing a variety of assessment techniques. These included contaminant analysis, a histological survey (the microscopic structure of animal tissues) and the documentation of observations by Inuit hunters, called Inuit Qaujimajatuqangit (IQ). Elders and hunters living in three eastern Arctic communities participated in the Nunavut Wildlife Health Assessment Project (NWHP) because they are concerned about the increased rate of physical changes they are seeing in species they rely on to maintain their way of life.

The NWHP is a joint initiative with the Hunters’ and Trappers’ Organizations/Associations (HTOs/HTAs) within the Nunavut communities of Arviat, Coral Harbour and Pangnirtung, WWF-Canada and researchers from Trent University. The primary goal of this three-phase project was to assess the impact of contaminants on the health of wildlife such as caribou, arctic char, ringed seal, beluga whale and polar bear.

“Greater attention needs to be directed towards wildlife health issues to determine the magnitude and significance of these changes to the long-term sustainability of Arctic wildlife,” said Dr. Gordon Balch, Research Associate at Trent University.

“This is particularly important in the context of climate change, which has a strong potential to influence the toxicological effects of Persistent Organic Pollutants (POPs),” said Dr. Susan Sang, a Senior Manager with WWF-Canada who headed up the study.

The histological survey found conditions in some tissues of seals and beluga which appeared unusual. These anomalies included reactive and / or draining lymph nodes (suggestive of infection in surrounding tissues), evidence of bacterial infection in liver tissue, and inactive spermatogenesis. As well, many legacy POPs such as polychlorinated biphenyls (PCBs) and DDT, banned for more than twenty years, were still present in the tissue of Arctic wildlife. Most of our toxicological information comes from the study of individual compounds, but little is known about the combined effect arising from contaminant mixtures (e.g. PCBs + DDTs + mercury). Even less is known about what cumulative impacts could occur when animals are exposed to both contaminants, plus the stress of climate related alterations to habitat (e.g. loss of food, competition from southern species, migration of pathogens and diseases).

Mercury, a potent toxic metal that targets the nervous system and brain development, was detected in various tissues and organs of Arctic char, ringed seals and beluga whales. The concentrations of total mercury increased from char to ringed seal to beluga demonstrating greater accumulation in those species closest to the top of the food chain. Much remains to be learned as to how mercury levels will affect predator-prey relationships in a changing environment. Mercury levels in the kidney and the liver of ringed seals, as well as muscle, kidney and liver in beluga are much higher than 0.5 ppm level recommended by Health Canada for human consumption.

The NWHP results also showed that new contaminants such as polybrominated diphenyl ether (PBDE) known as fire retardants, and the organochlorine insecticide endosulfan, were detected in species submitted for chemical analysis (e.g. arctic char, ringed seal, beluga whale). Although the environmental levels of these emerging contaminants are generally one to two orders of magnitude below the levels associated with the more notable legacy POPs, these compounds possess many of the same toxicological qualities of legacy contaminants and based on other studies, these levels are rapidly increasing in Arctic wildlife tissues. The biological impacts at these concentrations are largely unknown at this point.

These results are of concern given the reliance of Inuit communities on “country food” – food obtained through hunting and fishing from the sea, land, lakes and river by Inuit hunters.

Moe Keenainiak, Acting Executive Director of Qikiqtaaluk Wildlife Board, also stated, ”I believe that more research needs to be done on animals’ (health) to keep track of how things are going because country food is what we depend on to live.”

Inuit hunters and Elders believe that pollutants from afar, as well as those used locally like oil and gas spills from boats and land vehicles, are contaminating the Arctic environment and wildlife. Sixty per cent of those interviewed for the IQ Survey believe that any pollutants in Arctic environments would have a negative impact on the health of wildlife. “Country foods are a main source of the Inuit diet. There is great concern about the impact of contaminants on the health of wildlife, said Thomas Ublureak, President of Hunters’ and Trappers’ Organisation in Arviat.

“Continuation of sampling (wildlife) is the only way we are going to know about disease in these animals,” commented William Nakoolak, President of Hunters’ and Trappers’ Organisation in Coral Harbour.

The contamination of Arctic wildlife with chemicals, including some no longer used in most industrialized countries and many still used in industrial and consumer applications, demonstrates the ineffectiveness of health and environmental protection laws in Canada and elsewhere. European countries have taken a first step towards pollution prevention by requiring scientific data as a precondition for producing and marketing chemicals or products containing chemicals. The proposed Registration, Evaluation and Authorisation of Chemicals (REACH) system should lead to the identification and phasing out of the most harmful chemicals. WWF-Canada has urged the government, in the context of the current review of the Canadian Environmental Protection Act (CEPA), to pursue a similar approach to protect the environment, wildlife and humans from toxic chemicals.