Is the belugas immune system still intact?
Many chemical pollutants, including organochlorines, can weaken the immune system. As a logical follow-up to the pathologies observed in the necropsy room, scientists hypothesized that toxic chemicals present in the belugas might have compromised their immune system and directly caused some of the lesions endangering their health or survival.
To go through the looking glass
Lymphocytes are blood cells that play an important role in the immune system. These cells were extracted from samples taken from Arctic belugas and prepared as cell cultures, which were then exposed to different pollutants. Their efficiency was put to the test under the microscope.
When exposed to organochlorine concentrations comparable to those measured in St. Lawrence beluga tissues, these cells were not as efficient in performing their normal function. In 1996, an attempt was made to capture and temporarily hold a number of belugas in the St. Lawrence in order to obtain blood samples and to compare the efficiency of their immune cells with those of Arctic belugas. Unfortunately, field captures were unsuccessful and these questions remain unanswered.
Pierre Béland SLNIE, Michel Fournier and Sylvain Deguise, group at Université du Québec in Montréal, in collaboration with Université de Montréal, Environment Canada and the Department of Fisheries and Oceans Canada.
United States Environmental Protection Agency, Medical Research Council of Canada, Natural Science & Engineering Research Council of Canada (NSERC), Canadian Wildlife Toxicology Network, Wildlife Toxicology Fund, Corporation des Médecins Vétérinaires du Québec, World Wildlife Fund Canada, World Wildlife Fund USA, Montréal Biodome, Shedd Aquarium of Chicago.
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