Case study approach to modeling historical disinfection by-product exposure in Iowa drinking waters

作     者：Stuart W.Krasner Kenneth P.Cantor Peter J.Weyer Mariana Hildesheim Gary Amy 

作者机构：Metropolitan Water District of Southern CaliforniaWater Quality La Verne CA 91750 USA National Cancer InstituteNational Institutes of Health Bethesda MD 20892 USA Center for Health Effects of Environmental Contamination(CHEEC)University of Iowa Coralville IA 52242 USA Medical Research SolutionsLLC Montgomery Village MD 20886 USA College of EngineeringComputing and Applied SciencesClemson University Clemson SC 29631 USA 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2017年第29卷第8期

页      面：183-190页

核心收录：

学科分类：081702[工学-化学工艺] 08[工学] 0817[工学-化学工程与技术] 0815[工学-水利工程] 

基　　金：the Water Research Foundation the U.S.Environmental Protection Agency (USEPA) the Division of Cancer Epidemiology and Genetics of the National Cancer Institute (NCI) and CHEEC for their support of the Iowa epidemiologic study 

主　　题：Disinfection by products Trihalomethanes Haloacetic acids Exposure assessment Epidemiology Bladder cancer 

摘      要：In the 1980 s, a case–control epidemiologic study was conducted in Iowa（USA） to analyze the association between exposure to disinfection by-products（DBPs） and bladder cancer risk. Trihalomethanes（THMs）, the most commonly measured and dominant class of DBPs in drinking water, served as a primary metric and surrogate for the full DBP *** THM exposure was calculated, based on rough estimates of past levels in Iowa. To reduce misclassification, a follow-up study was undertaken to improve estimates of past THM levels and to re-evaluate their association with cancer risk. In addition, the risk associated with haloacetic acids, another class of DBPs, was examined. In the original analysis, surface water treatment plants were assigned one of two possible THM levels depending on the point of chlorination. The re-assessment considered each utility treating surface or groundwater on a case-by-case basis. Multiple treatment/disinfection scenarios and water quality parameters were considered with actual DBP measurements to develop estimates of past levels. The highest annual average THM level in the re-analysis was156 μg/L compared to 74 μg/L for the original analysis. This allowed the analysis of subjects exposed at higher levels（〉 96 μg/L）. The re-analysis established a new approach, based on case studies and an understanding of the water quality and operational parameters that impact DBP formation, for determining historical exposure.