Correlation Study on Clinical Laboratory Findings with Occupational Exposure to Low Dose Ionizing Radiation in Nuclear Workers in Korea / 한국역학회지

PURPOSE: Even though atomic energy and radioisotope had been made for a peaceful purpose, some of the public do't feel safe possibly due to potential exposure to ionizing radiation. While health effects of high level radiation are almost deterministic, the stochastic effects of the 'low-dose radiation' have not come to a correct conclusion. This correlation study was conducted to assess the health effect due to potential exposure th low-dose radiation in the nuclear power plants workers in Korea. METHODS: The study subjects was selected among the nuclear workers. Among those who attend the epidemiologic survey for screening of any malignancies done by the study group of Seoul National University Hospital during 1992-1993, 1) those who had undertaken both the physical examination with clinical laboratory tests and the direct interview with questionnaire, 2) male workers, and 3) those with record on radiation dosimetry as well as employment records in the company. Correlation analysis with Pearson's correlation coefficients and quantitative analysis with normal ranges of various tests were done by the PC-SAS for window. RESULTS: Total cumulative radiation doses was relatively low, ranging 1 mSv at the lowest to 391 mSv at the highest. Moreover, mostly 68.7% of the subjects was within lower limit of total cumulative doses under 10 mSv. Among the clinical laboratory test, statistical significant correlation was see in hemoglobin(HGB), creatinine(CRE), and carcinoembryonic antigen(CEA). CONCLUSION: This study concluded that health effect of occupational exposure to low-dose ionizing radiation is minimal or, if any, extremely lower than expected in the nuclear power plants workers in Korea. Major limitation of this study is that the healthy worker effect could not excluded. A large-scale prospective epidemiologic study on the relationship between radiation exposure and health hazard is needed to draw a more valid conclusion.

Prediction of future breast cancer mortality in Korea / 한국역학회지

A recent increase in the number of deaths and mortality rates of breast cancer occurred in Korean women. The increases shows a indirect increase in incidence of breast cancer. The number of deaths from breast cancer and the mortality rate in the future would be of use in the perspectives of breast cancer control and management in Korea. This study is to forecast cancer deaths and age-adjusted death rates in the future(2000-2015 year) by fitting modelling, assuming present trends continue. The number and mortality rate of breast cancer were fitted and estimated by simple linear regression mode. Estimated crude death rates for breast cancer per 100,000 persons were 5 person in 2000, 5.99 person in 2005, 6.98 person in 2010, and 7.79 person en 1015. The observed age-adjusted death rates per 100,000 persons were 1.08 person in 1980, 2.03 person in 1985, 2.49 person in 1990, and 3.29 person in 1995 and the estimated age-adjusted death rates per 100,000 persons were 4.01 person in 2000, 4.72 person in 2005, 5.42 person in 2010, and 6.14 person in 2015. Future estimated increase rate of the number of death is 2 times as many as the estimated rate in population-increase. Particularly noteworthy was an increasing tendency of the age-specific death rate with the ages in death, as like a mortality pattern of breast cancer in western females. These findings suggest that cohort effect might significantly contribute to the increase of the number and mortality of breast cancer in Korean women.