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Arsenic Drinking Water Violations Decreased across the United States Following Revision of the Maximum Contaminant Level
journal contribution
posted on 2019-09-05, 20:36 authored by Stephanie A. Foster, Michael J. Pennino, Jana E. Compton, Scott G. Leibowitz, Molly L. KileArsenic
poses a threat to public health due to widespread environmental
prevalence and known carcinogenic effects. In 2001, the US EPA published
the Final Arsenic Rule (FAR) for public drinking water, reducing the
maximum contaminant level (MCL) from 50 to 10 μg/L. We investigated
impacts of the FAR on drinking water violations temporally and geographically
using the Safe Drinking Water Information System. Violations exceeding
the MCL and the population served by violating systems were analyzed
across the conterminous US from 2006 (onset of FAR enforcement) to
2017. The percentage of public water system violations declined from
1.3% in 2008 to 0.55% in 2017 (p < 0.001, slope
= −0.070), and the population served decreased by over 1 million
(p < 0.001, slope = −106 886). Geographical
analysis demonstrated higher mean violations and populations served
in certain counties rather than evenly distributed across states.
The decline in violations is likely due to the adoption of documented
and undocumented treatment methods and possibly from reduced environmental
releases. Considering other studies that have shown decreased urinary
arsenic levels in the population served by public water systems since
the new standard, it may be inferred that the FAR is facilitating
the reduction of arsenic exposure in the US.