Department of Civil and Environmental Engineering, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia.
Department of Chemistry, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia.
Sci Total Environ. 2019 Nov 15;691:621-630. doi: 10.1016/j.scitotenv.2019.07.185. Epub 2019 Jul 13.
Disinfection byproducts (DBPs) in municipal supply water have been a concern. Many DBPs have been characterized as possible and probable human carcinogens, which can pose elevated cancer risks through lifetime exposure to municipal supply water. Few DBPs are regulated in many countries to control human exposure and risk from DBPs. In risk assessment studies, concentration of DBPs in water distribution systems is often used, whereas populations are typically exposed to indoor tap water. Through employing several techniques, DBPs can be reduced prior to water consumption, which is likely to reduce human exposure and risk of DBPs. This study investigated six indoor techniques in reducing trihalomethanes (THMs) and haloacetic acids (HAAs) in synthetic water and the effects of these techniques on exposure and risk. The techniques are: S1, S2: storing water in a refrigerator with and without lids respectively; S3, S4: boiling water for 1 min followed by storing in a refrigerator with and without lids respectively; S5, S6: filtering water using new and used granular activated carbon (GAC) filters and storing in a refrigerator without lids. Storing of water (S1, S2) reduced THMs in the range of 14.8-47.2% while boiling (S3, S4) and filtration (S5, S6) reduced THMs in the range of 77.3-92.8%. In S1-S4 techniques, HAAs were not reduced significantly while in S5 - S6 techniques, HAAs were reduced in the range of 64.7-69.8%. In S3-S6 techniques, overall cancer and non-cancer risks were reduced by 45.5-82.6% and 26.3-80.0% respectively. The findings might prove useful in understanding DBPs exposure, associated risks, strategies to minimize exposure to these contaminants and updating regulatory guidelines for better protection of health risks from DBPs.
饮用水中的消毒副产物 (DBPs) 一直备受关注。许多 DBPs 已被确定为可能和可能的人类致癌物，通过终生接触市政供水，这些物质会增加癌症风险。在许多国家，很少有 DBPs 受到监管以控制人类接触和 DBPs 风险。在风险评估研究中，通常使用水中 DBPs 的浓度，而人群通常接触的是室内自来水。通过采用几种技术，可以在饮用水之前减少 DBPs，这可能会降低人类接触和 DBPs 的风险。本研究调查了六种减少合成水中三卤甲烷 (THMs) 和卤乙酸 (HAAs) 的室内技术以及这些技术对暴露和风险的影响。这些技术是：S1、S2：分别将水储存在带盖和不带盖的冰箱中；S3、S4：将水煮沸 1 分钟，然后分别将水储存在带盖和不带盖的冰箱中；S5、S6：使用新的和用过的颗粒活性炭 (GAC) 过滤器过滤水，并将水储存在无盖的冰箱中。储水 (S1、S2) 可将三卤甲烷的浓度降低 14.8-47.2%，而煮沸 (S3、S4) 和过滤 (S5、S6) 则可将三卤甲烷的浓度降低 77.3-92.8%。在 S1-S4 技术中，HAAs 没有明显减少，而在 S5-S6 技术中，HAAs 减少了 64.7-69.8%。在 S3-S6 技术中，总体癌症和非癌症风险分别降低了 45.5-82.6%和 26.3-80.0%。这些发现可能有助于理解 DBPs 暴露、相关风险、最大限度减少接触这些污染物的策略以及更新监管指南，以更好地保护人类免受 DBPs 风险的影响。
