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.


  • Pod of beluga whales
  • Photo credit: © GREMM

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.

In short

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.

Project collaborators

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.

Scientific papers

Béland, P. 1996. The beluga whales of the St. Lawrence River. Scientific American May 1996: 74-81.

Béland, P., S. DeGuise, C. Girard, A. Lagacé, D. Martineau, R. Michaud, D. C. G. Muir, R. J. Norstrom, É. Pelletier, S. Ray et L. R. Shugart. 1993. Toxic compounds and health and reproductive effects in St.Lawrence beluga whales. J. Great Lakes Res. 19(4): 766-775.

Béland, P., S. DeGuise et R. Plante. 1992. Toxicologie et pathologie des mammifères marins du St-Laurent. Rapport pour le Fonds pour la toxicologie faunique du Fonds mondial pour la nature, mai 1992.

Jarman, W. M., R. J. Norstrom, D. C. G. Muir, B. Rosenberg, M. Simon et R. W. Baird. 1996. Levels of organochlorine compounds, including PCDDS and PCDFS, in the blubber of cetaceans from the west coast of North America. Marine Pollution Bulletin 32(5): 426-436.

Martineau D., K. Lemberger, A. Dallaire, P. Labelle, T. P. Lipscomb, P. Michel, I. Mikaelian. 2002. Cancer in wildlife, a case study: beluga from the St. Lawrence estuary, Québec, Canada. Environmental Health Perspectives. 110(3): 1-7.

Martineau, D., S. DeGuise, M. Fournier, L. Shugart, C. Girard, A. Lagacé et P. Béland. 1994. Pathology and toxicology of beluga whales from the St. Lawrence Estuary, Quebec, Canada. Past, present and future. Sci. Total Environ. 154: 201-115.

Muir, D. C. G., C. A. Ford, B. Rosenberg, R. J. Norstrom, M. Simon et P. Béland. 1996. Persistent organochlorines in beluga whales (Delphinapterus leucas) from the St. Lawrence River estuary. I. Concentrations and patterns of specific PCBs, chlorinated pesticides and polychlorinated dibenzo-p-dioxines and -dibenzofurans. Environmental Pollution 93 (2): 219-234.

Muir, D. C. G., C. A. Ford, R. E. A. Stewart, T. G. Smith, R. F. Addison, M. E. Zinck et P. Béland. 1990. Organochlorine contaminants in belugas, Delphinapterus leucas, from Canadian waters. Can. Bull. Fish. Aquat. Sci. 224: 165-190.

Muir, D. C. G., K. Koczanski, R. Rosenberg et P. Béland. 1996. Persistent organochlorines in beluga whales (Delphinapterus leucas) from the St. Lawrence River estuary. II. Temporal trends, 1982-1994. Environmental Pollution 93 (2): 235-245.

Norstrom, R. J., D. C. G. Muir, C. A. Ford, M. Simon, C. R. Macdonald et P. Béland. 1992. Indications of P450 monooxygenase activities in beluga (Delphinapterus leucas) and narwhal (Monodon monoceros) from patterns of PCB’ PCDD and PCDF accumulation. Marine Environmental Research 34: 267-272.