Relation between stillbirth and specific chlorination by-products in public water supplies
Relation between stillbirth and specific chlorination by-products in public water supplies
复制标题
DOI：
10.2307/3434997
复制
发表时间：
2000-09-01
影响因子：
10.4
通讯作者：
Allen, AC
中科院分区：
文献类型：
--
作者：
King, WD;Dodds, L;Allen, AC
在水处理过程中，氯与地表水中天然存在的有机物发生反应，产生许多副产品。在形成的副产物中，三卤甲烷（THMs）的浓度最高。我们进行了一项回顾性队列研究，以评估公共供水中总THM和特定THM水平与死产风险之间的关系。该队列是从加拿大新斯科舍省的一个基于人口的围产期数据库中收集的，包括1988年至1995年期间近50，000例单胎分娩。通过将分娩时母亲的居住地与公共供水中监测的特定THMs水平联系起来，对个体暴露进行分配。对所有死产和基于导致胎儿死亡的生理过程的死亡原因类别进行分析。总THMs和特定THMs均与死产风险增加相关。在溴二氯甲烷接触方面观察到最强的相关性，与接触浓度< 5微克/升的人相比，接触浓度大于或等于20微克/升的人的风险增加一倍（相对风险= 1.98，95%置信区间，1.23-3.49）。与THM暴露相关的窒息相关死亡的相对风险估计值大于不明原因死亡或死产的总体风险。这些研究结果表明，需要考虑与死产风险有关的特定氯化副产品，特别是溴二氯甲烷和其他相关副产品。对窒息死亡的更强影响的发现需要确认和对可能机制的研究。
During water treatment, chlorine reacts with naturally occurring organic matter in surface water to produce a number of by-products. Of the by-products formed, trihalomethanes (THMs) are among the highest in concentration. We conducted a retrospective cohort study to evaluate the relationship between the level of total THM and specific THMs in public water supplies and risk for stillbirth. The cohort was assembled from a population-based perinatal database in the Canadian province of Nova Scotia and consisted of almost 50,000 singleton deliveries between 1988 and 1995 Individual exposures were assigned by linking mother's residence at the time of delivery to the levels of specific THMs monitored in public water supplies. Analysis was conducted for all stillbirths and for cause-of-death categories based on the physiologic process responsible for the fetal death. Total THMs and the specific THMs were each associated with increased stillbirth risk. The strongest association was observed for bromodichloromethane exposure, where risk doubled for those exposed to a level of greater than or equal to 20 mu g/L compared to those exposed to a level < 5 mu g/L (relative risk = 1.98, 95% confidence interval, 1.23-3.49). Relative risk estimates associated with THM exposures were larger for asphyxia-related deaths than for unexplained deaths or for stillbirths overall. These findings suggest a need to consider specific chlorination by-products in relation to stillbirth risk, in particular bromodichloromethane and other by-product correlates. The finding of a stronger effect for asphyxia deaths requires confirmation and research into possible mechanisms.