论文部分内容阅读
一.引言虽然吸入放射性核素的研究尚未提供颗粒状或其它局灶性辐射源比均匀照射更具有危险性的证据,但是肺内α放射体核素的粒子致肺癌危险度的低估已被引起极大的关注,这导致了要求减低职业性照射和环境照射中钚的标准. 在1974年自然资源保护委员会向美国政府机构提出一份要求将钚粒子在肺中的容许肺负荷量减低115000倍的申请中就表示了这样一种关注(后来改为减低到1000～2000倍).这个请求是基于这样的论点,肺内含有低到0.07微微居里(后来增加到0.6微微居里)的α放射体粒子所致局部组织的损伤将会导致癌瘤发生,并且其癌瘤危险度为每
I. INTRODUCTION Although studies of inhaled radionuclides have not provided more dangerous evidence of particulate or other focal sources of radiation than homogeneous irradiation, the underestimation of the risk of lung cancer from particles of pulmonary alpha-radionuclide particles has been elicited Which led to the call for the reduction of plutonium in occupational exposure and exposure to the environment In 1974 the Natural Resources Defense Council made a request to U.S. government agencies to reduce the allowable lung load of plutonium particles in the lung by 115,000 times (Later changed to a decrease of 1000 to 2000) .This request is based on the argument that the lung contains α as low as 0.07 pico-Curie (later increased to 0.6 pico-Curie) Local tissue damage caused by radioactive particles will lead to cancer, and the risk of cancer each time