Caesium-137 or approximately 44 μg/kg) of caesium-137 (and 950 to 1400 rads), they die within 33 days, while animals with half of that burden all survived for a year. Accidental ingestion of caesium-137 can be treated with Prussian blue, which binds to it chemically and reduces the biological half-life to 30 days. Caesium-134 and caesium-137 were released into the environment during nearly all nuclear weapon tests and some nuclear accidents, most notably the Chernobyl disaster and the Fukushima Daiichi disaster. As of 2005 and for the next few hundred years, caesium-137 is the principal source of radiation in the zone of
Radiation effects from the Fukushima Daiichi nuclear disaster non-profit Radiation Effects Research Foundation said that people should not overreact, because there are no reports known of health problems with these levels of radiation. On 31 October 2011 a scientist from the Worcester Polytechnic Institute, Marco Kaltofen, presented his findings on the releases of radioactive isotopes from the Fukushima accidents at the annual meeting of the American Public Health Association (APHA). Airborne dust contaminated with radioactive particles was released from the reactors into the air. This dust was found in Japanese car filters: they contained caesium-134 and caesium-137, and cobalt at levels as high as 3 nCi total activity