Environmental radioactivity part of the Chernobyl release was the caesium-137, this isotope is responsible for much of the long term (at least one year after the fire) external exposure which has occurred at the site. The caesium isotopes in the fallout have had an effect on farming. A large amount of caesium was released during the Goiânia accident where a radioactive source (made for medical use) was stolen and then smashed open during an attempt to convert it into scrap metal. The accident could have been stopped at several stages; first, the last legal owners of the source failed to make arrangements
Caesium-137 in flow meters, thickness gauges, moisture-density gauges (for density readings, with americium-241/beryllium providing the moisture reading), and in gamma ray well logging devices. Caesium-137 is not widely used for industrial radiography because it is quite chemically reactive, and hence difficult to handle. The salts of caesium are also soluble in water, and this complicates the safe handling of caesium. Cobalt-60, , is preferred for radiography, since it is chemically a rather nonreactive metal and produces higher energy gamma-ray photons. As a purely man-made isotope, caesium-137 has been used to date wine and detect counterfeits and as a relative-dating material for