Fukushima Daiichi nuclear disaster (Unit 2 Reactor) the plant would be decommissioned once the crisis was over. The Japanese government estimates the total amount of radioactivity released into the atmosphere was approximately one-tenth as much as was released during the Chernobyl disaster. Significant amounts of radioactive material have also been released into ground and ocean waters. Measurements taken by the Japanese government 30–50 km from the plant showed caesium-137 levels high enough to cause concern, leading the government to ban the sale of food grown in the area. Tokyo officials temporarily recommended that tap water should not be used to prepare food for infants. In May 2012,
Caesium chloride dispersed in the environment in the event of an accident. For instance, radiothermal generators (RTGs) often use strontium titanate, which is insoluble in water. For teletherapy sources, however, the radioactive density (Ci in a given volume) needs to be very high, which is not possible with known insoluble caesium compounds. A thimble-shaped container of radioactive caesium chloride provides the active source. Caesium chloride is used in the preparation of electrically conducting glasses and screens of cathode ray tubes. In conjunction with rare gases CsCl is used in excimer lamps and excimer lasers. Other uses include activation of electrodes in welding;