Radiocesium in caribou and reindeer in northern Canada, Alaska and Greenland from 1958 to 2000
Autor: | Colin R. Macdonald, Bliss L. Tracy, Brett T. Elkin |
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Rok vydání: | 2007 |
Předmět: |
Canada
Potential impact Wet weight biology Health Toxicology and Mutagenesis Greenland General Medicine biology.organism_classification Pollution Geography Cesium Radioisotopes Environmental protection Herd Animals Environmental Chemistry Seasons Groenlandia Physical geography Waste Management and Disposal Alaska Ecosystem Radioactive Pollutants Reindeer |
Zdroj: | Journal of Environmental Radioactivity. 93:1-25 |
ISSN: | 0265-931X |
Popis: | This study summarizes the spatial and temporal trends of fallout 137 Cs concentrations in caribou and reindeer ( Rangifer tarandus ssp.), reported in various programs in Canada, Alaska and Greenland, over a 40-y period. During the 1960s, the highest 137 Cs concentrations (2000–3000 Bq kg −1 wet weight in muscle) were found in the large caribou herds of central northern Canada, with levels about 50% lower in Alaska and Greenland. Concentrations varied by up to a factor of 6 between spring and fall. Concentrations in reindeer were comparable to those in caribou from the same regions. The highest 137 Cs concentrations (750 Bq kg −1 ) in the late 1980s were found in the Caniapiscau herd of central Quebec. The contribution from the Chernobyl accident in 1986 was estimated from 134 Cs measurements to be 10–40% of the total 137 Cs. Present concentrations have declined to 200–300 Bq kg −1 . The effective half-life ( T eff ) of 137 Cs in Canadian caribou herds was estimated to be about 6 y. The potential impact on the health of northern residents is discussed. |
Databáze: | OpenAIRE |
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