[PLUTONIUM AND LIFETIME REDUCTION AMONG PROFESSIONAL WORKERS FSUE].

The objective of the study is the assessment of lifetime in the cohort of Mayak PA workers employed in 1948-1958 and exposed to incorporated Pu-239. The decrease of age at death 5.2 years among males and 6.6 years among females, and after the start of work--6.9 years among males and 7.7 years among females, with the increase of Pu-239 incorporation was shown. The association of the raised mortality rate from tumour causes is shown both among males and females, mainly due to malignant neoplasms of lung and live; which are organs of Pu-239 main deposition. For the first time related to Pu-239 incorporation decrease of age at death from tumour and non-tumour causes of main and secondary organs of deposition both among males and females was revealed. To assess the reduction of lifetime Years of Potential Life Lost (YPLL) were calculated per 10(5) person-years of potential life based on European gender standard. The calculations based on the obtained estimations showed significant dependence of YPLL on the level of Pu-239 incorporation. At that the main contribution to the increase of YPLL, i.e. to lifetime reduction, was due to radiation-induced decrease of the age at death as compared to radiation-induced increase of mortality rates.