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 Cs in the fish caught were not lower than immediately after the disaster. On 26 October 2012, TEPCO admitted that it could not stop radioactive material entering the ocean, although emission rates had stabilized. Undetected leaks could not be ruled out, because the reactor basements remained flooded. The company was building a 2,400-foot-long steel and concrete wall between the site and the ocean, reaching below ground, but it would not be finished before mid-2014. Around August 2012 two greenling were caught close to shore. They contained more than 25,000 becquerels (0.67 millicuries) of caesium-137 per kilogram (), the highest measured