Monitoring and Assessment

The testing of nuclear bombs in the atmosphere in the late 1950s and the early 1960s has led to widespread contamination of air, soil, water, and the biosphere. Many countries have started surveillance programs to monitor contamination. It can be assumed that the high contamination that was found, for instance, in the Scandinavian countries prompted efforts to enact the 1962 treaty of the ban on nuclear tests in the atmosphere. Since then the concentration levels of radionuclides in the environment has declined considerably partly due to decay and partly due to their removal to sinks where they are strongly bound and cannot be recycled into the biosphere. The basic idea of surveillance networks has changed from monitoring fallout, more or less as a means to follow the decline of the artificial contamination in the environment, to monitoring discharges from nuclear power plants and to preparing for the possibility of widespread contamination following a severe reactor accident or even nuclear warfare.