Caesium-137 alienation around the Chernobyl nuclear power plant. Together with caesium-134, iodine-131, and strontium-90, caesium-137 was among the isotopes distributed by the reactor explosion that constitute the greatest risk to health. The mean contamination of caesium-137 in Germany following the Chernobyl disaster was 2000 to 4000 Bq/m. This corresponds to a contamination of 1 mg/km of caesium-137, totaling about 500 grams deposited over all of Germany. In Scandinavia, some reindeer and sheep exceeded the Norwegian legal limit (3000 Bq/kg) 26 years after Chernobyl. As of 2016 the Chernobyl caesium-137 has decayed by half, but could have been locally concentrated by much
Caesium-137 meter distance. In the Acerinox accident of 1998, the Spanish recycling company Acerinox accidentally melted down a mass of radioactive caesium-137 that came from a gamma-ray generator. In 2009, a Chinese cement company (in Tongchuan, Shaanxi Province) was demolishing an old, unused cement plant and did not follow standards for handling radioactive materials. This caused some caesium-137 from a measuring instrument to be included with eight truckloads of scrap metal on its way to a steel mill, where the radioactive caesium was melted down into the steel. In March 2015, the Norwegian University of Tromsø lost 8 radioactive samples including