POPULATION DOSE LOADS IN PRIMORSKII KRAI FROM THE NUCLEAR ACCIDENT ON A SUBMARINE IN BUKHTA CHAZHMA

摘要

The population dose loads from the radioactive cloud and at residential sites in the contaminated area weredetermined. The dose was determined according to I131-135, Cs-137, Sr-90, and Co-60. The adjacent uninhabited Dunai Peninsula, Ussuriiskii Zaliv, Primorskii Krai, and China's Heilongjiang boundary province were considered. The effective dose of external irradiation on Dunai Peninsula was the highest. It reached 80 mu Sv at a distance of 1.2 km from the source. The effect of radiation dose to the internal organs was equal to 440 mu Sv, of which the lungs received 250 mu Sv and the thyroid gland 20 mu Sv. The dose is a factor of 10 lower 5.5 km from the accident site on the coastline of the zaliv. In the coastal zone, where the population lives, the dose corresponded to 0.1-2 mu Sv and reached 3-6 mu Sv at individual sites. In Primor'e, it varied from 0.01 to 0.1 mu Sv and on Chinese territory it did not exceed 0.01 mu Sv. In permanent residential areas, the effective dose of internal irradiation was determined by Co-60. For the first year, it was equal to 0.1-6 mu Sv for adults in the coastal area of Ussuriiskii Zaliv, 0.001-0.1 mu Sv on the territory of Primor'e, and 0.0005- 0.002 mu Sv on Chinese territory. For children, it could be 10-20 times higher as a result of the consumption of locally produced milk. In comparison with the global average background yearly irradiation dose 2400 mu Sv and the admissible value 1000 mu Sv, the contribution of the consequences of a nuclear accident on a nuclear submarine in Bukhta Chazhma was equal to 1-2%. No additional radiation protection measures were needed for the population.