三卤甲烷 (THM) 和硝酸盐是饮用水中广泛存在的化学物质。尽管没有确凿的证据，但长期暴露与癌症风险增加有关，部分原因是长期暴露评估和潜在暴露错误分类方面的挑战。我们使用 CONSTANCES 的公共监管监测数据库 (SISE-Eaux) 估算了饮用水中硝酸盐和 THM 的浓度，CONSTANCES 是一个基于法国人口的前瞻性队列。我们获得了 2000 年至 2020 年饮用水参数的 26,322,366 个测量值。我们排除了缺失、不可信和重复的测量值；我们更正或估算了采样位置缺失的地理编码；我们按监测区域计算了硝酸盐和三卤甲烷的年中位浓度。为了预测缺失的年中位浓度，使用监测区域作为聚类变量，分别为每个区域的硝酸盐和四种 THM 成分（氯仿、氯二溴甲烷、溴二氯甲烷和溴仿）开发了具有随机截距的线性混合模型。每年，对 2000 年至 2020 年居住历史进行地理编码的 75,462 名参与者中距离家庭最近的监测区域的集中情况进行合并。将这种方法得出的估计浓度与 2021 年在巴黎、雷恩和圣布里厄收集的 100 个样本的测量浓度进行了比较。2000-2020 年研究参与者家中总 THM 和硝酸盐的年浓度中位数分别为 15.7 μg/ l（IQR：15.2）和15.2 mg/l（IQR：20.8）。其中，35% 基于硝酸盐测量（16% 基于 THM），44% (46%) 使用线性混合模型预测，21% (38%) 基于分布单位中值。硝酸盐的条件 R2 预测模型范围为 0.71 至 0.91（中位数：0.85），THM 的条件 R2 预测模型范围为 0.48 至 0.80（中位数：0.68）。这些浓度将有助于未来与乳腺癌和结直肠癌风险的关联分析。我们在此介绍的清洁流程可以适用于其他大型饮用水监测数据。版权所有 © 2024。由 Elsevier Inc. 出版。

Trihalomethanes (THMs) and nitrate are widespread chemicals in drinking water. Chronic exposure has been associated with increased cancer risk despite inconclusive evidence, partly due to the challenges in long-term exposure assessment and potential exposure misclassification. We estimated concentrations of nitrate and THMs in drinking water using a public regulatory monitoring database (SISE-Eaux) for CONSTANCES, a French population-based prospective cohort. We obtained 26,322,366 measurements of drinking water parameters from 2000 to 2020. We excluded missing, implausible and duplicated measurements; we corrected or imputed missing geocodes of sampling locations; we calculated the annual median concentration of nitrate and THMs by surveillance area. To predict missing annual median concentrations, linear mixed models with random intercept using surveillance area as a clustering variable were developed for each region for nitrate and the four THM components (chloroform, chlorodibromomethane, bromodichloromethane and bromoform) separately. Concentrations in the nearest surveillance area from the household were merged per year among 75,462 participants with residential history geocoded for 2000-2020. Estimated concentrations resulting from this approach were compared with measured concentrations in 100 samples collected in Paris, Rennes and Saint-Brieuc in 2021. Median annual concentrations of total THMs and nitrate at study participants' homes for 2000-2020 were, respectively, 15.7 μg/l (IQR: 15.2) and 15.2 mg/l (IQR: 20.8). Among these, 35% were based on measurements for nitrate (16% for THMs), 44% (46%) were predicted using on linear mixed models, and 21% (38%) were based on distribution unit median values. Conditional R2 predictive models ranged from 0.71 to 0.91 (median: 0.85) for nitrate, and from 0.48 to 0.80 for THMs (median: 0.68). These concentrations will allow future association analyses with risk of breast and colorectal cancer. Our cleaning process introduced here could be adapted to other large drinking water monitoring data.Copyright © 2024. Published by Elsevier Inc.