Application Of Radiation Related Leukemia Risk In Chinese Population

Background As one causation of cancer, ionizing radiation can cause almost all kinds of cancer, and it has been proven by studies in the laboratory and epidemiology investigations. However, other than induced by occupational exposure, there are various kinds of risk factors, including natural source radiation, that can cause cancer. Cancer patients who have exposed to ionizing radiation of certain doses, can get compensation when the cancer is induced by previous radiation, but we have to calculate PC to determine the possibility. PC is defined as the possibility that cancer be induced by previous exposure, and is expressed in terms of percentage.In 1985, radioepidemiological tables was released by American, in this report it had developed the method to determine the causation by PC first time, and then accepted by radiation protection community of many countries. British, Japan, German, Indian and some other countries develop the method for calculating PC which is suitable for their own country according to the population data of each country. The current judgment criteria of our country,GBZ97-2009 "Judgment criteria for cause of radiogenic neoplasms ", which is a revision of GBZ97-2002,still judge the possibility by PC value, but most of the parameters used is from 1985 radioepidemiological tables (NIH85-2748),which is fitted through epidemiological investigation of Life Span Study in Japan and transformed to American. Because the baseline features are different, parameters for American are not suitable for Chinese. To obtain the radiation induced PC value suitable for Chinese, we have to get the method for calculating PC based on cancer baseline rate of Chinese population.Objective Take leukemia which can explicitly caused by radiation as example, to explore the method for calculation PC that suitable for Chinese population. So that we can transfer population risk directly from Japanese, through this method we can decrease the uncertainty in transfer.Material and Method We use ERR model released in 2006 BEIRⅦ report to estimate excess relative risk, and use the additive and multiplicative weighted average model in this report to transfer risk between population. In consistent with BEIRⅦ report, we regard all the sub-type leukemia as an entirety to calculate risk. Leukemia incidence rate of Chinese population are cited from Chinese cancer registry annual report 2009 part, and Japanese population rate are cited from The National Cancer Registry Center.Result We obtained the Chinese population leukemia ERR. For man the additive model weighted coefficient is 0.2 and the multiplicative coefficient is 0.8.For woman it is 0.15 and 0.85 respectively.Conclusion First We consider generally, contrast incidence rate between three countries, then adjust the weighted coefficients and calculate the ERR of Chinese population. We apply newly released incidence rate to transfer risk between Japanese population and Chinese population, through the new model we can transfer risk to Chinese more accurately.