Effect of Smoking on Chromosomes Compared with That of Radiation in the Residents of High Background Radiation Area in China

The health effects of low dose radiation is the most important subject in the field of radiation biology now. In the south of China there is a high background radiation area (HBRA) where the level of environmental natural radiation is about 3 to 5 times higher than that in a control area (CA). Major sources of higher background radiation in this area are nuclides of Th-232 and U-238 decay products in the soil and in the building materials. An epidemiological study conducted in HBRA and control area showed no statistically significant increase in either cancer morbidity or mortality. On the other hand, frequency of dicentrics plus rings, which are known to be radiation specific chromosome aberrations, in the lymphocytes of the residents in HBRA was higher than that in CA. Study of translocations could not detect difference in the frequencies between those two areas. In the present paper we describe the results of the study on the effect of smoking on chromosomes compared with that of radiation in those areas.International Workshop on High Background Radiation Area (HBRA) Studies in China, India, and Iran 中国、インド、イランの高自然放射線地域研究国際ワークショッ