Medical Radiology and Radiation Safety. 2015. Vol. 60. No. 6. P. 60-66

DISCUSSION

M.V. Osipov, M.E. Sokolnikov

Challenges in Carcinogenic Risk Assessment of Medical Radiation Exposure among Workers at a Nuclear Power Plant

Southern Urals Biophysics Institute of FMBA RF, Ozersk, Chelyabinsk Region, Russia, e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

ABSTRACT

Purpose: Explore an approach to the estimation of relative risk from medical radiation exposure and show a complex mechanism of causal relationship between exposure to medical radiation and the risk of cancer among Workers at a nuclear power plant.

Material and methods: The study has been carried out among Workers at the «Mayak» nuclear nuclear power plant. Nuclear workers underwent the combined exposure of chronic gamma and alpha ionizing radiation in a wide range of doses, and regular medical examination at the Central medical-sanitary unit of Ozersk. Information on vital status and cause of death was obtained from the Nuclear Personnel Register and the Oncological Register. The risk assessment was carried out on the basis of the excess relative risk model.

Results: The comparison of the coefficient of excess relative risk per unit dose obtained in the model for external professional and medical exposure showed that ERR per unit dose of medical radiation exposure (5.5 (95 % CI 0.3; 12.2) for solid cancers other than lung, liver and bone, is several times higher than one for occupational external gamma radiation exposure (0.13 (95 % CI 0.05; 0.2)). To a large extent, this is not due to a direct carcinogenic effect of medical radiation, but as a consequence of the effective detection of cancer by the X-ray.

Conclusion: The reason for bias in the estimation of excess relative risk of medical exposure is a reversed causal interaction between the analyzed factor and the effect. One of the possible solutions of to this problem is the risk of medical X-ray screening exposure (i.e. fluorography) analyses. Simple summation of doses of medical and occupational exposure to for calculating the risk is unacceptable due to the different mechanisms of accumulation of radiation dose.

Key words: medical exposure, absorbed dose, excess relative risk, medical radiation dose

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For citation: Osipov MV, Sokolnikov ME. Challenges in Carcinogenic Risk Assessment of Medical Radiation Exposure among Workers at a Nuclear Power Plant. Medical Radiology and Radiation Safety. 2015;60(6):60-6. Russian.

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