Chernobyl incident

The Chernobyl incident (April 1986) was the largest radiation exposure of recent times. Chernobyl resulted in a rapid increase in reactor power, vaporization of water in the reactor that blew the reactor core apart and destroyed most of the building. During that year, 220,000 people from areas near or surrounding the reactor were evacuated. Approximately 250,000 people were relocated from Belarus, the Russian Federation, and Ukraine. 

During the accident at the 850 MW Three Mile Island-2 nuclear reactor on March 28, 1979, an amount of Xe comparable to the Chernobyl incident was released. It is estimated that approximately 10 " Bq of radioxenon was released when fuel rods partially melted and radioactive noble gases vented into the atmosphere and into the reactor building through a pressure relief valve that stuck open. Elevated Xe levels were detected as far away as 375 km in Albany, NY where a peak atmospheric concentration of approximately 144 Bq/m was measured. ... 

Bettoh, M.G., Sabatini, A.G. and Vecchi, M.A. (1987). Honey produced in Italy since the Chernobyl incident. Apitalia 14, 5-7. 

Consequently, although there was discussion in several countries soon after the Chernobyl incident... 

All gamma-spectrometric measurements showed values of contamination by Cs 137 exceeding significantly the clearence level. By means of the relations of activities of Cs 137/Cs 134, it was possible, however, to prove that this contamination was due to the Chernobyl incident and not due to the THTR 300 operation. 

Following the Chernobyl incident in 1986, many different radioisotopes were released. Some, such as iodine-131, had decayed almost completely in a matter of several weeks. However others, such as strontium-90 (% = 29 years) and caesium-137 (ti = 30 years), will remain in food chains and the soil for over 300 years. 

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