Science Inventory

POU Water Filters Effectively Reduce Lead in Drinking Water: A Demonstration Field Study in Flint, Michigan

Citation:

Bosscher, V., D. Lytle, M. Schock, A. Porter, AND M. Deltoral. POU Water Filters Effectively Reduce Lead in Drinking Water: A Demonstration Field Study in Flint, Michigan. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH, PART A. Taylor & Francis Group, London, Uk, 54(5):484-493, (2019). https://doi.org/10.1080/10934529.2019.1611141

Impact/Purpose:

Water sampling data from this study indicates that POU filters are a reliable method to reduce both soluble and particulate lead (well above 150 µg/L) down to low levels. Over 97% of filtered water samples contained lead below 0.5 µg/L, and the maximum lead concentration in filtered water was 2.9 µg/L, well below the bottled water standard. POU water filters can be an important and reliable barrier against unpredictable lead release from LSLs and plumbing materials. This study shows that POU water filters can be an important and reliable barrier against unpredictable lead release from LSLs and plumbing materials. 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 absorption 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 not would result in a significant increase in overall lead exposure.

Description:

A field study was conducted to test the effectiveness of faucet-mounted point of use (POU) water filters for removing high concentrations of lead that can occur in drinking water due to plumbing sources including 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. Water sampling data indicates that POU filters are a reliable method to reduce both soluble and particulate lead (well above 150 µg/L) down to low levels. Over 97% of filtered water samples contained lead below 0.5 µg/L, and the maximum lead concentration in filtered water was 2.9 µg/L, well below the bottled water standard. POU water filters can be an important and reliable barrier against unpredictable sporadic lead release from LSLs and plumbing materials. 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 absorption 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 not would result in a significant increase in overall lead exposure