Environmental Radiocesium in Subarctic and Arctic Alaska Following Chernobyl

Radiocesium ('34Cs and '37Cs) concentrations were measured in soil, plant and wildlife samples from subarctic to arctic Alaska. Concentrations of 13'Cs ranged from below detectable or low levels in whale and fish samples to as high as 242 Bqkg in lichen. For all potential human food items, the radiocesium concentrations measured in this study were below accepted permissible levels for human consumption. Chemobyl-derived radiocesium concentrations ranged from below detectable or low levels in all arctic samples (soil, sediment, lichen, whale, fish and caribou) to 32 Bqkg in subarctic moss. Therefore the distribution and subsequent deposition of Chemobyl-derived radiocesium appears to be variable but decreasing significantly from the Subarctic (Fairbanks) to the Arctic. The present data support the suggestion that Chemobyl-derived debris arrived from westem Canada into central Alaska and subsequently moved to the north (arctic) and to the west, decreasing in the quantity deposited as the debris transversed the state.