Overview of the Radiological Accidents in the World, Updated December 1989

Abstract

Radiological accidents can be divided into two categories, depending on whether the accident involves large groups of the population with relatively low doses or a few individuals with high doses resulting in acute health effects. The accidents involving large groups are related to the dispersion of radioactive materials in the environment; although they may have different causes, the source is always very important. Most of the accidents which have occurred originated in civilian installations; two reactor accidents can be considered without any human consequences: the accidents in the UK (Windscale) in 1957 and in the USA (TMI) in 1979. The Chernobyl accident (USSR) in 1986 resulted in extensive contamination of the environment, with non-negligible doses to the population around the plant and large collective doses in the northern hemisphere; in addition, the Chernobyl accident caused the deaths of 31 workers and firemen who intervened to bring the installation back under control. Violations of the most elementary safety rules for the operation of medical sources were at the origin of two severe environmental contaminations with human consequences: in Mexico (1983-4) and Brazil (1987), with sources of 60Co and 137Cs, respectively. The accidents concerning only a few individuals are not always known with the same documented accuracy. Between the 1940s and 1960s six critical accidents caused eight deaths; since then only one has occurred, in Argentina in 1983. The fatal radiation accidents are due to high-energy radiation sources, such as 60Co, 137Cs, and 192Ir. The total number of deaths which has been registered is 28. The accidents related to internal exposure are not exceptional, but result very rarely in health consequences.

Transplacental Transfer of Radionuclides. A Review

“…It has been shown in the past that the peaceful and controlled use of nuclear energy does not exclude major nuclear accidents with environmental contamination (NENOT, 1990). Considering the extreme radiosensitivity of the embryo and foetus (CAYWOOD et al, 1997;MOLE, 1993), the question of transplacental radionuclide transfer is of great importance.…”

Civilian nuclear incidents: An overview of historical, medical, and scientific aspects

“…Largest releases took place on April 26, May 4, and May 5. [20] The meteorological situation at the time of the accident resulted in the radioactive plume moving northward toward the town of Pripyat and further toward Belarus and Northern Europe. This spared the highly populated cities immediately to the south including Kiev (3 million residents).…”

“…[20] Both occurrences affected large populations and covered large geographic areas. Incidents involving nuclear power plants in the United States, including the Three Mile Island (TMI) power plant, although very serious, fortunately did not result in significant contamination of the surrounding areas.…”

Epidemiology of accidental radiation exposures.

“…Accidents limited to a few exposed persons are much more frequent than those yielding global environmental contamination and may go unreported. Most of the known accidents resulted in relatively high doses to small numbers of persons (7). Table 1 summarizes the main events that have resulted in large-scale radiation exposures.…”