进行了一项现场研究,以测试安装在水龙头上的使用点(POU)滤水器从前提管道源和铅服务线(LSL)中去除饮用水中高浓度铅的有效性。这些过滤器同时根据NSF/ANSI标准53(NSF/ANSI-53)进行了总铅去除认证,并根据NSF/ANSI标准42(NSF/ANSI-42)进行了细颗粒(I类)减少认证。2016年,在弗林特的345多个地点收集了过滤和未过滤的饮用水样本。密歇根。超过97%的过滤水样中铅含量低于0.5µg/L。过滤水中的最大铅浓度为2.9µg/L,远低于瓶装水标准。POU活性炭块过滤器在降低铅浓度方面的有效性,甚至高于150µg/LNSF/ANSI-53挑战标准,由于过滤器的有效孔径小,可能与捕集颗粒有关,除了离子交换或吸附去除可溶性铅。正确安装和维护POU过滤器,NSF/ANSI-53(总铅)和NSF/ANSI-42(细颗粒)认证,可以保护所有的人口,包括孕妇和儿童,通过将饮用水中的铅降低到不会导致总体铅暴露显着增加的水平。
A field study was conducted to test the effectiveness of faucet-mounted point of use (POU) water filters for removing high concentrations of lead in drinking water from premise plumbing sources and lead service lines (LSL). These filters were concurrently certified for total lead removal under NSF/ANSI Standard 53 (NSF/ANSI-53) and for fine particulate (Class I) reduction under NSF/ANSI Standard 42 (NSF/ANSI-42). In 2016, filtered and unfiltered drinking water samples were collected at over 345 locations in Flint, Michigan. Over 97% of filtered water samples contained lead below 0.5 µg/L. The maximum lead concentration in filtered water was 2.9 µg/L, well below the bottled water standard. The effectiveness of the POU activated carbon block filters in reducing lead concentrations, even above the 150 µg/L NSF/ANSI-53 challenge standard, is likely related to trapping particles due to the small effective pore size of the filters, in addition to ion-exchange or sorption removal of soluble lead. Properly installed and maintained POU filters, certified under both NSF/ANSI-53 (for total lead) and NSF/ANSI-42 (for fine particulate), can protect all populations, including pregnant women and children, by reducing lead in drinking water to levels that would not result in a significant increase in overall lead exposure.