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
Fukushima Daiichi nuclear disaster On 13 February 2014, TEPCO reported 37 kBq (1.0 microcurie) of caesium-134 and 93 kBq (2.5 microcuries) of caesium-137 were detected per liter of groundwater sampled from a monitoring well. Dust particles gathered 4 km from the reactors in 2017 included microscopic nodules of melted core samples encased in caesium. After decades of exponential decline in ocean caesium from weapons testing fallout, radioactive isotopes of caesium in the Sea of Japan increased after Fukushima from 1.5 mBq/L to about 2.5 mBq/L and are still rising as of 2018, while those just off the western coast of Japan have declined. According