Across the US, ensuring safe water supply for communities remains to be a growing challenge as the country suffers from aging infrastructure, impaired source water, and strained community finances, explained Maura Allaire, Haowei Wu, and Upmanu Lall in their research “National Trends In Drinking Water Quality Violations.” Published in peer-reviewed journal portal PNAS (Proceedings of the National Academy of the United States of America), the authors said efforts to minimize violations are of national concern considering that in 2015, nearly 21 million people depended on community water systems that violated health standards.
Allaire and colleagues used a panel dataset of 17,900 community water systems (CWS) over the period 1982-20165. They found that 9% of CWs in their sample violated health-based water quality standards in 2015, affecting 21 million. During the past 34 years, nine to 45 million people were affected, constituting 4 to 48% of the US population. The authors’ data contained the number of CWS that serve 87% of the population supplied by the CWS in the continental US.
They found that about 8.0% of the 608,600 utility-year observations had some sort of health-based violation, while 4.6% had a total coliform violation. This totaled to 95,754 health-based violations and total coliform was the most prevalent type of violation as it accounted for 37% of all violations. Fecal coliform violations are relatively rare, occurring only 2,138 times during the study period. Violations classified as “other” contaminants comprised 36% of violations while violations of treatment rules and nitrates are less common, representing only 21% of the total violations.
Alarmingly, the US is suffering right now from water contamination due to “forever chemicals” or PFAS (Perfluoroalkyl and Polyfluoroalkyl Substances), which is worse than scientists thought, reported Reuters, via British newspaper The Guardian.
Americans’ Perceptions of the Pollution of Drinking Water
Justin McCarthy of management consulting company Gallup found in their survey (March 1 to 5, 2017) that 63% of Americans worried a great deal about pollution of drinking water, up from 61% in 2016 and 2015’s 55%. Further, 57% of respondents worried a great deal about pollution of rivers, lakes, and reservoirs, an increase from 56% (2016) and 47% (2015). Gallup first polled on environmental issues in 1989 and tracked these issues regularly in 1999.
Since then, between 48% and 72% of respondents have worried a great deal about the pollution of drinking water. On the other hand, between 46% and 66% worried a great deal about the pollution of rivers, lakes, and reservoirs. Across income groups, 75% of Americans earning less than $30,000 each year were concerned a great deal about the pollution of drinking water unlike those in middle-income ($30,000 to $74,999, 62%) and upper-income households ($75,000+, 56%).
What is PFAS or Forever Chemicals?
PFAS are known as “forever chemicals” as they do not break down once they are in the environment and they even build up in our blood and organs, according to Sydney Evans and colleagues of EWG (Environmental Working Group), an American activist group that focuses research on drinking water pollutants, toxic chemicals, and more. According to the authors’ report, exposure to PFASincreases the risk of cancer, affects the development of the fetus, and reduces the effectiveness of vaccines.
The Centers for Disease Control and Prevention (CDC), the US’s leading national public health institute, showed that the blood of nearly all Americans is contaminated with PFAS, cited Evans and colleagues. In fact, EWG’s previous estimate in 2018 that 110 million Americans might be contaminated with PFAS could be too low.
The most notorious PFAS compounds are PFOA— which is used by DuPont to make Teflon— and PFOS, a former ingredient in 3M’s Scotchgard. The aforementioned compounds have been phased due to the pressure from the EPA. However, they still present in drinking water, people, and the environment.
High Levels of PFAS
Evans and colleagues reported that the highest levels of PFAS contamination are found in major metropolitan areas, including Miami, Philadelphia, New Orleans and New York City’s northern New Jersey suburbs. The highest of which was in Brunswick Country, N.C. at 186 part per trillion (PPT). Of the tap water samples taken from 44 sites in 31 states and Washington DC, only Meridian, Mississippi— which relies on 700ft-deep wells— had no detectable PFAS. Moreover, PFAS levels below 1 PPT— a level EWG recommended— are present in Seattle and Tuscaloosa, Alabama.
Of 44 samples, PFOA was detected in 30 samples and PFOS in 34 samples, comprising a quarter of the total PFAS levels in each sample. David Andrews, a senior scientist at EWG and co-author of the report, “It’s nearly impossible to avoid contaminated drinking water from these chemicals.” The report also found that an average of six to seven PFAS compounds were found at the tested sites, with the impacts of the mixtures on health are little understood.
Apparently, the Environmental Protection Agency (EPA) or state environmental agencies have not publicly reported on PFAS contamination in 34 places where EWG tested PFAS levels. Since PFAS is not regulated, utilities that chose to test independently are not obligated to publicize their results or relay them to state drinking water agencies or the EPA.
Addressing PFAS Contamination
The EPA has known about PFAS contamination in drinking water since at least 2001, but has failed to establish an enforceable, nationwide legal limit. Last year, the EPA said it would begin to set limits on PFOA and PFOS. It explained that it aided states and communities in addressing PFAS and working to limit the chemicals, but it did not give a specific timeframe.
Removing PFAS from drinking water requires a case-by-case evaluation to determine the best course of action, as well as to design and install a treatment facility. There has been no simple and inexpensive technology for effectively removing the chemical from drinking water.
Granular activated carbon (GAC) is the most common option as it’s already been used by many water treatment facilities to remove other contaminants. Reverse osmosis is a great alternative, but it’s the costliest. Ion exchange is a newer technology for removing PFAS, though this option has a limited number of current installations.
Federal and state policymakers should formulate science-based drinking water standards for PFAS in tap water, slash ongoing PFAS discharges into water supplies, and end non-essential uses of the chemical. Policymakers should also so mandate the reporting of ongoing PFAS discharges into water supplies, ensure that the wastes are disposed of, and expand monitoring efforts.
Recently, Congress enacted legislation about the latter, but lawmakers failed to create drinking water standards for most states, regulate ongoing PFAS discharges into drinking water supplies, or eradicate legacy PFAS contamination.
Ensuring access to safe water supply remains to be a challenge for Americans, with the majority of them concerned about the pollution of drinking water. With PFAS present in nearly all Americans, the government needs to mandate the reporting of PFAS releases to water supplies to ensure the health of consumers.