核燃料元件厂和气体扩散厂工人死因回顾性调查

Radioepidemiological studies on workers in uranium fuel plants and gaseous diffusion plants

本研究对核燃料元件厂和气体扩散厂职工１９７１～１９８５、１９８６年期间受照剂量及死因进行了回顾性调查，结果是放射组职工人均年剂量低于１ｍＳｖ，至１９８５年底的累积剂量１０ｍＳｖ左右。观察放射组３６５２人，对照组５３９３人，两组分别累积５３８１３和８１６５０人年。全死因死亡：放射组１０４例（死亡率１９３．２６×１０－５），对照组２５３例（死亡率３０９．８６×１０－５），其中癌症死亡前者４９例（死亡率９１．０６×１０－５），后者８２例（死亡率１００．４３×１０－５）；全死因死亡率经年龄调整后，两组间差异无显著性，死亡按１９７３～１９７５年全国癌亡率为标准计算ＳＭＲ，两组间差别亦无显著性，并且均小于１。因此，在低水平辐射环境中未见癌症增加现象。

This retrospective study of causes of death includes workers in nuclear fuel element plants and gaseous diffusion plants. The observation popultion consisted of 3652 workers in exposure group and 5393 workers in control group,with 53813 and 81650 person-years in the above two groups respectively during the period from 1971 to 1985 (1986) .The individual committed effective dose was less than 1 mSv per year and the accumulative dose was about 10 mSv in the period. In the observation period, 104 and 253 persons died in the exposure and control groups,repectively.The numbers of cancer death in these two groups were 49 and 82, respectively. The crude mortality rates were 193.26×10-5/person years and 309.86×10-5/person years, the cancer mortality rates were 91.06×10-5/person years and 100.43×10-5/person years, respectively.There was no significant difference in crude mortality rates betweenthe two groups after age adjustment. For standardized mortality ratio (SMR) of cancer,the calculation was carried out in the light of national survey of this SMR in small cities in 1973-1975.The results showed that SMRs of both groups were less than 1 and there was no significant difference between the two groups. So,there was no evidence of incidence increment of radiogenic cancer in workers exposed to low-level ionizing radiation.