Dosimetry of 210Po in humans, caribou, and wolves in northern Canada.

Effective doses from 210Po intake with caribou meat were determined for human residents in Baker Lake and Snowdrift in the Northwest Territories of Canada and compared to doses calculated from reported 210Po tissue activities in Alaskan and British residents (Hill 1966; Blanchard and Moore 1971). Effective doses were calculated to separate body tissues, using ICRP 60 human weighting factors and the ICRP 30 metabolic model for 210Po. Baker Lake and Alaskan effective doses were similar at 0.4 mSv y-1 and slightly higher than Snowdrift doses (0.3 mSv y-1). Alaskan tissue activities indicated higher effective doses to liver, bone surfaces and red marrow and lower doses to spleen than the 210Po metabolic model (ICRP 1979a) predicts. Effective doses to Baker Lake and Snowdrift caribou and wolves, calculated from tissue activities, ranged from 7-20 mSv y-1, using human weighting factors for comparison to human doses only. Effective doses to northern Canadians and wildlife were, respectively, 7-11% and 1.8-5 times an estimated human background of 4 mSv y-1 from all sources.