[link to www.nuc.berkeley.edu]
Fukushima hot particles By Marco kaltofen

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The Fukushima nuclear accident dispersed airborne dusts that are contaminated with radioactive particles. When inhaled or ingested, these particles can have negative effects on human health that are different from those caused by exposure to external or uniform radiation fields. A field sampling effort was undertaken to characterize the form and concentration of radionuclides in the air and in environmental media which can accumulate fallout. Samples included settled dusts, surface wipes, used filter masks, used air filters, dusty footwear, and surface soils. Particles were collected from used motor vehicle air filters and standard 0.45 micron membrane air filters. Soils and settled dusts were collected from outdoor surfaces, interior surfaces, and from used children’s shoes. The Japanese filters contained cesium 134 and 137, as well as cobalt 60 at levels as high as 3 nCi total activity per sample.