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
Caesium-137 assessing the age of sedimentation occurring after 1954. Caesium-137 is also used as a radioactive tracer in geologic research to measure soil erosion and deposition. Caesium-137 reacts with water, producing a water-soluble compound (caesium hydroxide). The biological behavior of caesium is similar to that of potassium and rubidium. After entering the body, caesium gets more or less uniformly distributed throughout the body, with the highest concentrations in soft tissue. The biological half-life of caesium is rather short, at about 70 days. A 1972 experiment showed that when dogs are subjected to a whole body burden of 3800 μCi/kg (140 MBq/kg,