Characteristics of the cohort of workers at the Mayak nuclear complex.

At Branch No. 1 of the Russian State Research Center "Biophysics Institute", a registry has been created of workers at the "Mayak" Production Association, the first nuclear complex in Russia. This registry includes 18,830 persons hired at Mayak's nuclear reactors and radiochemical and plutonium production plant between 1948 and 1972. Twenty-five percent of these workers are women. As of December 31, 1994, the vital status is known for approximately 90% of the cohort members. A total of 5,118 persons have died. The cause for 97% of total deaths has been ascertained. The cohort members were exposed to both external gamma radiation and internal radiation from incorporated plutonium. The plutonium body burden has been measured in 30% of the cohort members with potential for plutonium exposure. External gamma-ray doses were in the range from tenths of milligrays to about 10 Gy, and plutonium body burdens were up to about 260 kBq. In view of the nature of the Mayak worker cohort, it has the potential to provide reasonably precise, quantitative estimates of the long-term health effects associated with chronic low-dose-rate exposure to external gamma radiation as well as internal radiation from plutonium. However, a number of issues must be addressed before credible risk estimates can be obtained from this cohort. These issues include the development of an appropriate internal comparison group and/or external rates and separating of the effects of internal and external exposures on risk estimates.

[Interactions of radiation factors and smoking in the etiology of lung cancer in workers of atomic enterprises]. / Vzaimodeistvie radiatsionnykh faktorov i kureniia pri razvitii raka legkogo u rabotnikov atomnogo predpriiatiia.

It was shown on the basis of retrospective investigation of 500 workers at a nuclear enterprise (162 cases of lung cancer, 338 persons as matching control) that the interaction of external gamma-irradiation (> 2.0 Gy) and the body-burden of 239Pu (> 9.3 kBq) at lung cancer incidence in multiplicative. Combined influence of smoking and radiation factors was found dependent on smoking index (SI): it changed from additive up to multiplicative and than to antagonistic with the increase of the smoking effect. The received results could be explained on the basis of a two-mutation model of radiation carcinogenesis.

Estimation of the temporal distribution and dose dependency of lung cancers among workers of nuclear fuel reprocessing plants.

Lung cancer mortality among 4,279 workers at the Mayak nuclear complex who were exposed to chronic irradiation both externally and internally from incorporation of plutonium was analyzed in terms of a linear relative risk model. It is estimated that excess lung cancer risk is about 1.9 Sv(-1), with an average latent period of 24 y.

[Evaluation of the effects of biological and clinical factors on plutonium excretion in man]. / Otsenka vliianiia biologicheskikh i klinicheskikh faktorov na urovni vyvedeniia plutoniia iz organizma cheloveka.

The values of the natural urine excretion coefficient in 84 workers have been received. The observations were ranging from 1970 to 1984. To analyse this data the references about radiobiological, medical, anthropometrical and other factors which potentially influence osteotropic radionuclide excretion in man and animals have been studied. By means of linear regression (program KWAZAR) it was confirmed that 6 factors including liver and heart diseases were important. Mathematical description of this results is suggested.

[Wounds and burns of the skin polluted by alpha irradiation in personnel of radiochemistry enterprises]. / Rany i ozhogi kozhi, zagriaznennye alfa-izluchateliami, u personala radiokhimicheskogo predpriiatiia.

Records of pollution by plutonium and americium 241 of skin wounds and burns in the personnel of the Mayak plant in 1948-1992 are analyzed. Traumas occurred in 286 (7.2%) workers, mechanical injuries were 84.1% of these. A high incidence of wound contamination was recorded in the workers engaged in mechanical processing of plutonium. Altogether 34.1% of injuries had alpha-radiators in residual amounts after debridement, though their levels did not surpass the minimal levels of radionuclide detection.