Aquatic Toxicity Workshop 2010

I just recently returned from the Aquatic Toxicity Workshop, held this year in Toronto, Ontario. The four day conference is designed to bring industry, private consultants, and academics together to present and discuss new research in aquatic toxicology. Toxicology is the study of poisons (or contaminants) and aquatic toxicologist study the movement of these contaminants through aquatic ecosystems. This year the theme was, "Big cities - Big challenges - Great solutions: urbanization and environmental impacts".  The theme was specific, but the talks spanned a much wider range of issues from contaminants leeching out of the Alberta tar sands, to the impacts of pesticides and herbicides on forest-dwelling amphibians, to the impacts of migration on mercury loading in birds.



Overall, the message was clear: we have far too many existing and emerging contaminants in the environment that continue to require  monitoring and laboratory testing. In the Great Lakes the major contaminants of concern include: PCBs, Mirex, Dioxin, Toxaphene, and mercury, all of which are considered 'legacy contaminants' -  those we have been monitoring for several decades.  The image below was taken from the U.S. Environmental Protection Agency website and lists those legacy contaminants that are causing fish consumption advisories in the Great Lakes.

Emerging chemicals of concern for the Great Lakes include BPA, flame retardants, pharmaceuticals, paraffins, and pesticides and probably many others. These contaminants generally can't be attributed to direct point-source of pollution; rather they are often byproducts of consumer goods that end up as waste in the our waters. The consequence is that these are the ones for which we have very little information, yet they may pose very dangerous risks to humans and wildlife now and in the future.

The major bi-national agreement addressing toxins in the Great Lakes is the Canadian-American, Great Lakes Water Quality Agreement (GLWQA),  signed in 1972.  It was established largely because of the visible impacts pollutants were having in the lakes and under the agreement both countries must work towards the virtual elimination of persistent contaminants in the basin. There has been some progress toward meeting this goal, but even as some reports cite drastic reductions in contaminants like mercury and PCBs, we still have fish consumption advisories in all the lakes. I think its high time the GLWQA is revisited to better coordinate restoration cleanup efforts of a resource that 40 million Canadians and Americans depend on every day.