Cancer mortality risk among workers at the Mayak nuclear complex.

At present, direct data on risk from protracted or fractionated radiation exposure at low dose rates have been limited largely to studies of populations exposed to low cumulative doses with resulting low statistical power. We evaluated the cancer risks associated with protracted exposure to external whole-body gamma radiation at high cumulative doses (the average dose is 0.8 Gy and the highest doses exceed 10 Gy) in Russian nuclear workers.

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.

Mortality among personnel who worked at the Mayak complex in the first years of its operation.

Epidemiological studies revealed increased cancer mortality among persons who began working at the Mayak complex during the period 1948-1958. Estimation of cancer risk was carried out for the sites of cancer that showed increased mortality and dependence on dose of external gamma- or internal alpha-irradiation.

Mortality among workers with chronic radiation sickness.

This study is based on a registry containing medical and dosimetric data of the employees who began working at different plants of the Mayak nuclear complex between 1948 and 1958 who developed chronic radiation sickness. Mayak is the first nuclear weapons plutonium production enterprise built in Russia and includes nuclear reactors, a radiochemical plant for plutonium separation, and a plutonium production plant. Workers whose employment began between 1948 and 1958 exhibited a 6-28% incidence of chronic radiation sickness at the different facilities.

[Changes in the structure and metabolism of rat thymus nucleic acids following cessation of long-term administration of different doses of tritium oxide].

A study was made of the processes of restoration of metabolism and nucleic acid indices in rat thymus after the cessation of the long-term administration of various doses of tritium oxide. The restoration of the indices under study was only observed after tritium dose of 0.37 MBq(g.