Carcinogenicity of radiation doses caused by the Chernobyl fall-out in Sweden, and prevention of possible tumors.

Abstract

The fallout from the Chernobyl reactor resulted in radioactive fall-out in eastern Sweden leading to a ground radiation intensity of between 2 and 500 microR h-1 above the 10-15 microR h-1 background, an average external cumulative dose of about 3-4 mSv (0.3-0.4 rem) to about 1 million people, or about 3500 man-Sv (350,000 man-rem) over 50 years, or 70 man-Sv per year with a maximum dose to a few individuals of 40 mSv. The corresponding figures reported for civilians around Chernobyl is 8.6 million man-rem in 1986 and 29 million man-rem over 50 years, or 600,000 man-rem (equivalent to about 6000 man-Sv) per year. If Swedish doses are averaged over the whole population, the average is about 1 mSv or 10,000 man-Sv, or 200 man-Sv per year. The thyroid uptake of 131I is approximately 0.1-0.2 kBq (0.005 microCi) and the total body uptake of 137Cs, 1 kBq (0.03 microCi), resulting in an approximate internal dose of 0.02 mSv. If a linear dose-response curve is assumed, an increase of the normal cancer mortality incidence in the million Swedes affected by 3500 man-Sv per 50 years from 200,000 to about 200,070 can be assumed. Corresponding figures for all of Sweden are 8,000,000 inhabitants, 7000 man-Sv, 1,720,000 normal cancer deaths, and 1,720,140 expected cancer deaths. Corresponding figures reported for the population outside the 30 km evacuation zone around Chernobyl are 300,000 man-Sv, and an increase from 6,800,000 cancer deaths per 50 years to 6,806,000 cancer deaths.