An Observational Study of Pigs Exposed to Radiation

On June 28, 2011, 26 pigs were rescued from the alert area, 17 km northwest of the Fukushima Daiichi Nuclear Power Plant, where radiation levels were approximately 1.9–3.8 μSv/h. The pigs were transferred outside of the radiation alert area to the Animal Resource Science Center (ARSC), The University of Tokyo. It was confirmed by the farm owner that the pigs were never fed radiation-contaminated concentrate and they had access to uncontaminated groundwater (http://www.env.go.jp/press/press.php?serial=16323) while living inside the radiation alert area; however, radiocesium was detected in the rescued pigs’ organs, testis/ovary, spleen, liver, kidney, psoas major, urine, and blood, within nine months after the nuclear disaster. Radiocesium levels in samples collected in early January 2012 were significantly lower than those collected in either early or late September 2011, indicating a continuing decrease in radiation levels over that duration. Radiocesium was not detected in organs collected in August 2012. In September 2011, the authors of the present study visited a local farm to collect samples from pigs who remained inside the radiation alert area. Radiocesium concentration in these pigs was nearly ten times higher than from the rescued pigs.