Radiation effects from the Fukushima Daiichi nuclear disaster PBq of caesium-137. In May 2012, TEPCO reported that at least 900 PBq had been released "into the atmosphere in March last year [2011] alone" up from previous estimates of 360-370 PBq total. The primary releases of radioactive nuclides have been iodine and caesium; strontium and plutonium have also been found. These elements have been released into the air via steam; and into the water leaking into groundwater or the ocean. The expert who prepared a frequently cited Austrian Meteorological Service report asserted that the "Chernobyl accident emitted much more radioactivity and a wider diversity of radioactive elements than Fukushima
Caesium lethal within three weeks; smaller amounts may cause infertility and cancer. The International Atomic Energy Agency and other sources have warned that radioactive materials, such as caesium-137, could be used in radiological dispersion devices, or "dirty bombs". Caesium Caesium (IUPAC spelling) or cesium (American spelling) is a chemical element with symbol Cs and atomic number 55. It is a soft, silvery-gold alkali metal with a melting point of 28.5 °C (83.3 °F), which makes it one of only five elemental metals that are liquid at or near room temperature. Caesium has physical and chemical properties similar to those of rubidium