General Conclusions

Abstract

For a number of reasons, CRS is still little known as a distinct radiation-related pathology in man. Although clinical manifestations of the CRS were in detail described by Russian scientists as early as the 1950s, the first concise description of CRS was only presented by IRP in 2007 in Publication 103. The complex of symptoms which develops in individuals in cases of long-term (months to years) total-body exposures was designated by the term “chronic radiation syndrome.” Insufficient familiarity of the scientific community with CRS evidently resulted from the fact that cases of CRS were registered long ago (mostly in the 1950s) and predominantly in the Southern Urals. Cases of CRS among workers of the Mayak PA and residents of the Techa riverside villages were registered during the so-called cold war when the Soviet Union was speeding up the implementation of its atomic project with the aim to attain parity with the United States in terms of atomic weapons. The imperfections of the nuclear technologies and the system of radiation protection led in a number of cases to long-term (for years) radiation exposures of the workforce and the population at doses exceeding the threshold values for development of organ (tissues) effects. Beginning from the 1960s, as the technologies and radiation conditions at the atomic facilities were improving, new cases of CRS ceased to be identified. That is why, some researchers have gained an impression that the conditions for the development of CRS can hardly emerge nowadays, and, consequently, this pathology is no longer relevant. Nevertheless, the interest in the CRS phenomenon has not declined, a fact that can be accounted not only for a potential threat of situations involving long-term exposure of humans to radiation (e.g., astronauts under the conditions of long-term space flights, or general population in case of terrorist acts, etc.). Analysis of CRS cases can also provide an insight into the response of the human body at large to long-term whole-body radiation exposures and the relationship between the late (cancer and non-cancer effects) and early deterministic effects.