By L. R. Mark Hall
March 2004A thesis submitted in partial fulfillment of the requirements for the degree of Mater of Science in Environment and Management Abstract This research is a preliminary investigation into one potential fate of persistent organic pollutants that occur in the mountains of Western Canada. Seven of the world’s twelve most toxic chemicals described in the Stockholm Convention are deposited from the atmosphere into the mountains of Western Canada. This condition places the health of humans and wildlife in the region at risk. As the wildlife species topping a terrestrial food chain that humans are considered a part of, cougars (Felis concolor) and wolves (Canus lupus) were analyzed to determine if the persistent organic pollutants are bio-accumulating in the food chain. Based on an analysis of cougar and wolf tissues, the concentration levels for all the chemicals tested were below the detection limits achieved in the analysis; however, there is the potential for falsely accepting these apparent negative results. Six factors potentially explain the apparent absence of chemicals from the ungulate-cougar/wolf food that include: (1) the use of low elevation habitat by some ungulates in the winter, (2) the ability of wolves to metabolize some types of chemicals, (3) filtering of semi-volatile pollutants by forests, (4) potential inability of the cascade food chain model to predict the most susceptible species in complex food chains, (5) detection limits that potentially were not low enough and (6) analytical error introduced from the dilution effect. These factors suggest that persistent organic pollutants might still occur in the food chain despite the results of this study but at concentrations below the detection limits achieved and the most susceptible species might not necessarily be cougars or wolves. The study recommends that the Ministry of Water, Land and Air Protection in British Columbia consider the potential adverse health affects of toxic chemicals in the environment as a threat to wildlife species when preparing recovery strategies for an endangered species. As a signature to the Stockholm Convention on Persistent Organic Pollutants, the governments of Canada, particularly Health Canada and the BC provincial Ministry of Health, have an international obligation to conduct further research on persistent organic pollutants in the mountains of Western Canada. To download Mark Hall’s thesis, click here (411 kb PDF file). [Back to Research Highlights] |
