Results of studies of high Cs-137 body burdens in Alaskan Eskimos showed a good correlation between body burden and urinary excretion rate. Composite samples of urine from groups of people can be analyzed with the help of this correlation to obtain values of the average body burden of Cs-137 for the group.
Measurements of the cesium-137 content of northern Alaskan Natives during the summer of 1964 indicated that the adults of the interior village of Anaktuvuk Pass had the highest average body burden: 1280 nanocuries of cesium-137. This is an increase of 200 percent over the average body burden found in the summer of 1962 and 100 percent over that found in the summer of 1963. The greatest burden found in a native in 1964 was 2.4 microcuries of cesium-137, but the highest burden of all, 3.0 microcuries, was measured in a non-native living mainly on caribou meat. Sodium-22 was found in samples of urine from Eskimos, and subsequently in the Eskimos themselves and in reindeer and caribou meat.
From: Fortuine, Robert et al. 1993. The Health of the Inuit of North America: A Bibliography from the Earliest Times through 1990. University of Alaska Anchorage. Citation number 857.