Специфика риска радиогенного рака для профессиональных работников

Abstract

Purpose: Analysis of the dependence of the probability of death due to radiogenic cancer on the dose level, on the nature of exposure to ionizing radiation (IR), on age when exposed to IR and on the age of its effect, etc., to support decisions on medical and social measures to protect workers in hazardous industries.
 Material and methods: Calculation formulas for risk assessment are given using the multiplicative and additive risk models for one-time and extended exposure to IR. Medical and demographic data for the urban population of the Chelyabinsk region for 1989 were taken as necessary baseline data for risk assessment. The risk was calculated using the combined BEIR VII and EPA models.
 Results: The risk is calculated in terms of annual or lifetime risk of death from spontaneous and radiogenic solid cancer for two scenarios of occupational exposure to IR (single and extended), for a set dose of 0.5; 1; 2 Sv and different ages of survival of a person who started work in production at the age of 20.
 Conclusions: 1. For small and moderate doses (D ≤ 1 Sv), prolonged exposure in the age range of 20–30 years leads to less risk than with short-term exposure at the age of 20 years with the same dose. This effect is absent for irradiation after 30 years. 2. The risk of death from spontaneous solid cancer is somewhat less for exposed people than for non-exposed people. Reason: radiogenic cancer begins to compete with spontaneous one. 3. With relatively small integral doses (< 1 Sv), the radiogenic risk linearly depends on the dose. At moderate and high doses (≥ 1 Sv), for continuous extended exposure the dose dependence becomes nonlinear. 4. The probability of causation of death from radiogenic solid cancer for older people and for doses of D ≥ 1 Sv becomes significant, especially for women (30 % and more in relation to spontaneous solid cancer). 5. The lifetime risk of radiogenic cancer from the dose received at working age decreases significantly with age when it reaches 60 years of age.