Radiocaesium contamination of wild boars in Fukushima and surrounding regions after the Fukushima nuclear accident.

Analysis of radioactivity data obtained under the food monitoring campaign in Japan indicates that elevated (134)Cs+(137)Cs activity concentrations in wild boar meat remained constant or slowly decreased in Fukushima and surrounding prefectures from 2011 to 2015. The activity concentrations in some samples are still over the regulatory limit of 100 Bq kg(-1) fresh weight, even in 2015. Activity concentrations of (137)Cs in muscle of wild boars we captured in 2011 were higher than those in kidney, liver, spleen, heart and lung. A food processing retention factor, Fr, was 0.5 or 0.6 for (137)Cs when the wild boar meat was boiled, suggesting that a parboiling process is effective for reduction of radiocaesium intake from wild boar meat.