STORY: About 700 beluga whales live in Canada's Saint Lawrence River, between Lake Ontario and the Atlantic Ocean. These easy-to-spot white whales have been protected from hunters since 1978, but scientists think chemical pollution might threaten them more than guns or harpoons ever did.
Pierre Beland has studied beluga whales in the Saint Lawrence for 16 years. He's a biologist for the Saint Lawrence National Institute of Ecotoxicology. Since 1982, he and his colleagues have performed autopsies on more than 100 whales, and they're startled by what they've discovered.
BELAND: "Well, we learned that these animals were dying of diseases that were rarely found and in many cases had never been reported before in whales. And we found that these animals were very highly contaminated. They were loaded with organochlorine chemicals like PCBs and DDT. They were loaded with heavy metals like mercury and lead."
Beland says the water in the Saint Lawrence River is relatively clean. But the eels and fish that belugas eat are another story--they're contaminated with chemical pollution from industries and cities that surround the nearby Great Lakes. The whales accumulate the contaminants when they eat the eels and fish. Even more of a concern to Beland is the alarming incidence of disease and cancer in beluga whales. He says about one-third of the whales eventually die from cancer, a rate that is the highest in the world.
BELAND: "That is the most striking observation from that population. I think that of the 100 or so animals we've autopsied we have described a number of cases of cancer that amount to one-half the amount of all cases of cancers reported in all whales around the world. That is an incredible statistic. We have more cases of cancer than anybody else."
Beland believes the chemicals are responsible for high rates of cancer in the belugas.
BELAND: "It could be related to some of the toxins in their bodies. We know for example that they're exposed to benzoate pyrene, which is one of the most potent carcinogens known. We also know that these animals, because of some of the chemicals in their bodies, may have a depressed immune system. There may be a link between toxic chemicals and the ability of the immune system to target and destroy cancer cells."
Beland says more research is needed to understand the plight of beluga whales remaining in the Saint Lawrence River and that efforts to clean up the river and the nearby Great Lakes should continue.
OUTRO: For Arctic Science Journeys, this is Doug Schneider reporting from Fairbanks, Alaska.
Arctic Science Journeys is a radio service highlighting science, culture, and the environment of the circumpolar north. Produced by the Alaska Sea Grant College Program and the University of Alaska Fairbanks.
Alaska Sea Grant Homepage
The URL for this page is http://seagrant.uaf.edu/news/98ASJ/08.31.98_BeleagBelugas.html