Estimation of Radiation Exposures of “Liquidators” of the Chernobyl Nuclear Power Station: Identification of Risk Groups

Abstract

Identification of workers who are at high risk and at low risk as a result of participation in the cleanup of the consequences of the accident at the Chernobyl nuclear power station (“liquidators”) is important both for scientific research and for the medical care of the individuals involved. Using register data for 36,700 liquidators, the authors estimated the relationships between radiation doses and the following factors: time of arrival at the accident zone, irradiation conditions, and possible health effects following the exposures. The analyses took into account types of work (decontamination, cordon work, building); places and circumstances of work (inside or outside or with machinery); and the use of individual protection measures. Included in possible effects on health were changes in hematologic indexes, weakness, headache, dryness or tickling of the throat, cough, facial hyperemia, metallic taste, anorexia, nausea, vomiting, heaviness in the epigastric region, and instability of defecation. With the help of mathematical models, the rating for each factor was assessed, and on this basis the liquidators were subdivided into risk groups. For workers for whom dose information was not available, probable doses could be calculated. The three most influential variables were time of starting work, type of work done, and the number of health effects.

Keywords:

• occupational radiation exposure
• acute radiation effects
• exposure assessment
• long-term radiation effects
• interaction of radiation and other exposures
• occupational disability