Wednesday, December 3, 2008

Pesticide contamination in Antarctic krill

A new study published recently in the journal Science of the Total Environment provides a very necessary "baseline assessment" of the level of organohalogen compounds (POCs) present in Antarctic krill. The paper itself is a bit dense for the nonscientist, but is very important. POCs comprise chemicals such as pesticides, PCBs, and other compounds that are considered pollutants. While the levels of POCs have been studied extensively in the Northern Hemisphere, they have not been researched as extensively in the Southern Hemisphere. Now that Southern Hemisphere countries are using these compounds in greater amounts, it is important to know how they are affecting marine life. The researchers found that some chemicals, such as PCBs, were lower in Antarctic krill than in their Artic counterparts. The main contaminants in the Antarctic krill samples were organochlorine pesticides.

Pesticides, including DDT, do have some benefits. Some credit DDT for helping reduce the burden of malaria in the developing world, and others credit pesticides with helping increase agricultural productivity. Nevertheless, these compounds do tend to accumulate in the environment, and tend to accumulate in greater amounts at the top of the food chain, which can have devastating impacts on some organisms, particularly another important source of human food - fish. This study provides precisely the kind of information that will help policymakers weigh the costs and benefits of using pesticides. The baseline established will provide useful data for understanding the impact of increasing pesticide use around the world.