Bates M N, Smith A H, Cantor K P
Department of Biomedical and Environmental Health Sciences, School of Public Health, University of California, Berkeley.
Am J Epidemiol. 1995 Mar 15;141(6):523-30. doi: 10.1093/oxfordjournals.aje.a117467.
Mortality from several cancers, including bladder cancer, is elevated in a Taiwanese population exposed to high levels of arsenic in drinking water. Data from the Utah respondents to the National Bladder Cancer Study conducted in 1978 were used to evaluate these associations in a US population exposed to measurable, but much lower, levels of drinking water arsenic. Two indices of cumulative arsenic exposure were used, one representing total cumulative exposure (index 1) and the other, intake concentration (index 2). Overall, there was no association of bladder cancer with either measure; however, among smokers, but not among nonsmokers, positive trends in risk were found for exposures estimated for decade-long time periods, especially in the 30- to 39-year period prior to diagnosis. Exposures were in the range 0.5-160 micrograms/liter (mean, 5.0 micrograms/liter). The data raise the possibility that smoking potentiates the effect of arsenic on risk of bladder cancer. However, the risk estimates obtained are much higher than predicted on the basis of the results of the Taiwanese studies, raising concerns about bias or the role of chance. Confirmatory studies are needed.
在台湾饮用高砷含量饮用水的人群中，包括膀胱癌在内的几种癌症的死亡率有所上升。1978年美国全国膀胱癌研究中来自犹他州受访者的数据，被用于评估美国一个饮用水砷含量可测量但低得多的人群中的这些关联。使用了两种累积砷暴露指数，一种代表总累积暴露（指数1），另一种是摄入浓度（指数2）。总体而言，膀胱癌与这两种测量方法均无关联；然而，在吸烟者中，而非不吸烟者中，发现了长达十年时间段内估计暴露量的风险呈正趋势，尤其是在诊断前30至39岁期间。暴露量范围为0.5至160微克/升（平均5.0微克/升）。这些数据增加了吸烟增强砷对膀胱癌风险影响的可能性。然而，获得的风险估计值远高于基于台湾研究结果的预测值，引发了对偏差或偶然性作用的担忧。需要进行验证性研究。
