Chernobyl disaster to residual radioactivity from Chernobyl in the plants they graze on in the wild during the summer. 1,914 sheep needed to be given uncontaminated feed for a period of time before slaughter during 2012, and these sheep were located in just 18 of Norway's municipalities, a decrease of 17 from the 35 municipalities affected animals were located in during 2011 (117 municipalities were affected during 1986). The after-effects of Chernobyl were expected to be seen for a further 100 years, although the severity of the effects would decline over that period. Scientists report this is due to radioactive caesium-137 isotopes
Radiation effects from the Fukushima Daiichi nuclear disaster Iwate), in Saku, Karuizawa and Sakuho (prefecture Nagano, in Tabayama (prefecture Yamanashi) and elsewhere. Based on radiation measurements made all over Japan between 20 March and 20 April 2011, and the atmospheric patterns in that period, computer simulations were performed by an international team of researchers, in cooperation with the University of Nagoya, in order to estimate the spread of radioactive materials like caesium-137. Their results, published in two studies on 14 November 2011, suggested that caesium-137 reached up to the northernmost island of Hokkaido, and the regions of Chugoku and Shikoku in western Japan at more than 500 kilometers