Environmental impact of nuclear power materials decay, they release particles that can damage the body and lead to cancer, particularly cesium-137 and iodine-131. In the Chernobyl disaster, releases of cesium-137 contaminated land. Some communities, including the entire city of Pripyat, were abandoned permanently. One news source reported that thousands of people who drank milk contaminated with radioactive iodine developed thyroid cancer. The exclusion zone (approx. 30 km radius around Chernobyl) may have significantly elevated levels of radiation, which is now predominantly due to the decay of cesium-137, for around 10 half-lives of that isotope, which is approximately for 300 years. Due to the bioaccumulation of
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;