Cancer risk analysis of possible Ionizing Radiation Exposure workers in enterprises with Poisson Regression Model.

• Main Authors: Ming-Chung Hsieh, 謝明忠
• Other Authors: Pao-Shu Chang
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/69715304876891867263

碩士 === 高雄醫學大學 === 職業安全衛生研究所 === 101 === Background: In Taiwan, there are many kinds of Ionizing Radiation-related workplaces, including Nuclear Power Plants, Medical Careers, Nuclear Engineering, Radiation Detection and etc. Hundreds of thousands employees are engaged in radiation-related works. According to Article 14 of Labor Health Protection Rules (LHPRs), amendment on January 21, 2011, enterprises with labors engage in operations with special health hazards (e.g. ionizing radiation) from Article 2 of LHPRs, must establish health data manager system, and implement the classifications of health manger system. We would like to analyze cancer risk of those workers who might be possible exposed to ionizing radiation in their past working history with Poisson Regression Model. Materials and Methods: Our objects are cancer cases in enterprises and with radiation exposure in Taiwan from year 1992 to 2010. Totally, we collected 84 cancer cases, and 34,404 person years. The collected data of 84 cancer employees included gender, exposure time and working areas. We grouped these workers into northern and southern areas by their working areas. Considering the latency period of radiation induced cancers, we set up criteria to exclude those workers whose exposure time is less than 5 years and working time is less than 10 years. We also excluded 3 female cases, because the case number is too few. Finally, 62 male workers’ data are suitable to input Poisson Regression Model. For the 62 workers, we grouped them into 1 year, 5 years and 10 years groups, to explore the cancer risk between different eras. Results: Our study results show that in groups of 1 year, cancer risk of northern working area is higher 0.14 time than southern, which is not statistically significant. In groups of 5 years, cancer risk of northern working area is 0.14 time than southern, and is not statistically significant. In groups of 10 years, cancer risk of northern working area is 0.14 time than southern, which is not statistically significant. Conclusions: In the Poisson Regression Model cancer risk analysis shows that in groups of 1 year, the cancer risk is not statistically significant. In groups of 10 years, cancer risk of the group 1992~1999 is 0.12 time higher than group 2000~2010, this trend is similar to the atomic bomb survivors’ Life Span Study (LSS) cohort in Japan, that is, cancer risk is higher when exposed at younger ages.