226Ra and other radionuclides in water, vegetation, and tissues of beavers ( Castor canadensis) from a watershed containing U tailings near Elliot Lake, Canada

• Published in: Environmental pollution (1987) 1991, Vol.69 (4), p.277-310
• Main Authors: Clulow, F.V., Mirka, M.A., Davé, N.K., Lim, T.P.
• Format: Article
• Language: English
• Subjects: Animal, plant and microbial ecology; Applied ecology; Biological and medical sciences; Castor; chemical constituents of plants; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on vertebrates; Fundamental and applied biological sciences. Psychology; Mammalia; phytotoxicity; pollution; radionuclides; water quality
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/0269-7491(91)90118-G

Radionuclide levels were measured in tissues, gut contents, diet items, and water at site of capture, of adult beavers from the Serpent River drainage basin which contains U tailings at Elliot Lake, Ontario, and from nearby control sites. Levels of 226Ra in beaver bone, muscle and kidney were highest in animals from locations close to U tailings; liver levels did not vary by site. Environmental 226Ra levels were within ranges previously reported at these or similar locations elsewhere; levels in beaver gut contents reflected levels in diet items. Concentration ratios exceeded unity only between some vegetation items and beaver bone at the Elliot Lake site and were less than 0·19 between vegetation and other tissues. In two beavers with tissue levels of 226Ra higher than other sampled, neither 232Th nor 230Th were detected in bone, muscle or liver tissues. U-238 was measurable in bone, muscle and liver, 228Th in bone, 210Po bone, muscle and liver; and 210Pb was measurable only in bone. Estimated yearly intakes of radionuclides by people eating beavers were calculated to be below current allowable levels set by the Canadian regulatory authorities.