Chlorine Disinfection Of Drinking Water And Bladder Cancer, Epidemiological Studies Of Lymphocytes In The Genetic Material Injury Contact

Objective: In order to understand the association between the exposure of chlorinated water and risk of bladder cancer, human lymphocyte抯 germ plasm damage in Chongqing, Studies were made to accumulate data concerning epidemiological study on carcinoma caused by chlorinated water. Methods: Case-control study of bladder cancer and exposure of chlorinated water was conducted during 1998-2000 in Chongqing area. The relevant factors in a total of 211 histological verified bladder cancer cases and 230 other cases controls which matched by age, sex and the years of residence in Chongqing were analyzed by comparision. Subjects were interviewed with questionnaires.at the same time, micronucleus test and comet assay were applied to compare the human lymphocyte's germ plasm damage of 100 people who have been drinking chlorinated water at all time with 90 controls drinking purified water. Data were gathered and processed with EPI 5.01 and SPSS 10.0 software package. Results:1.Results of case-control study:he single factor analysis indicated drinking chlorinated water and being exposed by skin were risk factors for bladder cancer, in addition to other risk factors like smoking, drinking, mental pressure, history of genetic and diseases of urinary system. 甌he odds ratio were over 2.5 for bladder cancer increased for people drinking chlorinated water more than 35 years and 1 500m1 every day. The years drinking chlorinated water (OR1 .437, 95%C11 .11 9? .865) and consumption of chlorinated water every day (OR1 .224, 95%CI= 1.050? .428) had entered into multivariate logistic regression model. 2.Results of epidemiological study on spot:~DChloroform in chlorinated water of the Factory of Wangjiang(A area) and Zhongliangshan mineral water Factory(B area) were 47.2igIL and 42.5tg/L respectively.~In A area, The micronucleus frequency(0.92%o) and proportion of the fourth-class cells DNA damage (5.18%) of people who drinking chlorinated water were higher than those of controls respectively. ?In B area, the micronucleus frequency (0.78%o) and proportion of the fourth-class cells DNA damage (2.88%) of people who drinking chlorinated water were much higher than those of controls respectively. ?the micronucleus frequency (1.31 %o )and proportion of the fourth-class cells DNA damage (6.08%) of people who drinking chlorinated water more than 45 years were higher than those of group under 35 years respectively. ?smoking was an important confusion factor for lymphocyte's germ plasm damaged by drinking chlorinated water. Conclusion: 1.Exposure to chlorinated water maybe a risk factors for bladder cancer in Chongqing.2.Lymphocyte's germ plasm could been damaged by drinking chlorinated water for a long time.