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Chemical Cocktails

What makes you most hopeful for the future?
Michaud: “I have seen people's attitude toward nature and society move by their encounters with wildlife and with whales in particular...”

See Robert Michaud's full Q&A »

DeGuise: “Open-minded people. It is really exciting to get students thinking differently from what they are used to, get them excited and help them succeed...”

See Sylvain DeGuise's full Q&A »

In the northern waters of Canada's St. Lawrence River, biologists have discovered pods of beluga whales with some of the highest cancer rates of any wild animal studied. Dozens of chemicals have been discovered in the bodies of these belugas. Some dead belugas are so full of pollutants and chemical mixtures from the water that they technically qualify as hazardous waste. It's these chemical mixtures, as opposed to any one chemical in particular, that are causing scientists like biologist Robert Michaud to worry. Michaud has spent two decades studying belugas, photographing them, tracking them, performing genetic analyses on their populations, trying to understand their lives and the impact of chemicals on these animals.

Pathologist Sylvain DeGuise draws blood samples from healthy belugas at the Mystic Aquarium in Connecticut. Back at his lab, he tests the sensitivity of the whale's immune cells to a variety of chemical cocktails. In his research, DeGuise has found that two chemicals individually may not be toxic but when mixed may turn toxic. Their toxicity is not due to a simple doubling of the dosage. Instead their toxicity spawns from the interactions between the two chemicals. Furthermore, DeGuise has found that combinations of multiple chemicals can act synergistically, antagonistically or neutrally. The possible number of interactions is overwhelming given the fact that the US Federal Government alone registers an average of 2,000 newly synthesized chemicals each year.

References
» Visit Whales Online Off-site Link for more in-depth information on the belugas and a wide variety of ongoing whale research projects.
 
» To find out more about whales and how you can become involved in whale research visit the Center for Whale Research. Off-site Link
 

Next: Chemicals and Human Reproduction »


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