What Are Safe Levels of PFOA and PFOS in Drinking Water?

What Are Safe Levels of PFOA and PFOS in Drinking Water?

There is a lot of discussion these days about safe levels of PFOA and PFOS in drinking water. For decades these chemicals were used in a variety of commercial products, from stick-free cookware to stain resistant clothing. Recent scientific studies have raised concerns about the existence of these chemicals in public drinking water sources.

While PFOA and PFOS are a cause for concern, they are not a cause for outright alarm. It’s important to understand the facts so you can make an informed decision about how best to protect yourself and your family.

PFAS, PFOS, and PFOA: What You Need to Know

PFOA and PFOS (Perfluorooctanoic acid and perfluorooctane sulfonate, respectively) are human-made chemical compounds frequently found in water as a result of industrial runoff.  Somewhat confusingly, PFOA and PFOS belong to a larger group of compounds known as perfluoroalkyl substances (PFAS). For the purposes of this article, we’ll be using the terms more or less interchangeably, as all of these are chemicals that have been linked to long-term malignant health effects in humans.

PFAS were phased out in 2015 but since these pollutants contain strong chemical bonds which don’t break down, their impact is still wide-reaching today. That’s why they’ve earned the nickname “forever chemicals” in the press.

Here are a few of the scientific studies that indicate the scope of the problem:

With all this data, it’s no wonder that there is concern among public health professionals about the quality of drinking water potentially contaminated by PFOA and PFOs.  

What Are Safe Levels of PFAS in Drinking Water?

According to the EPA’s health advisory, a safe level of PFOA and PFOS in drinking water is about 70 ppt (parts per trillion). About 10 U.S. states have taken matters into their own hands and recommended stricter limitations on the existence of these chemicals, however. For example, California has drafted a public health goal of 10 ppt for PFOA and 40 ppt for PFOS. (For context—one part per trillion is roughly equal to 1 grain of sand in an Olympic swimming pool.)

To date, lawmakers have faced many challenges in their efforts to enact effective legislation on this issue, and unfortunately the stalemate does not show any signs of ending any time soon. 

Is There Regulation of PFAS in Drinking Water?

The federal government’s recommendation of 70 ppt is just that – a recommendation. Health advisories are non-enforceable and non-regulatory. They are meant to provide a margin of protection to the public. The EPA is charged with then providing technical information and treatment technologies associated with drinking water contamination. It is then up to the states to pass official legislation.

As of this writing, 7 states have made recommendations that are more stringent than the EPA’s health advisory. The states with stricter regulation of PFAS in drinking water are:

  • New York
  • Massachusetts
  • New Hampshire
  •  Vermont
  • New Jersey
  • Minnesota
  • Michigan

Several other states have adopted a standard equal to 70 ppt (Alaska, New Mexico, Colorado, Ohio, Delaware, Connecticut, and Maine). One state, North Carolina, has adopted a standard that allows for a higher level of PFAS than the federal recommendation.

Why Is It Difficult to Regulate Drinking Water Purity?

Frustratingly, each state makes its recommendations based on different scientific data. The studies these recommendations were based on all looked at potential impacts on different groups.

For example, one state might be evaluating the health impacts of PFOS in drinking water for pregnant women, while another looks at impacts of PFOA on children, and a third looks at potential toxicity for all PSAS for all adults. You can begin to see how complications arise as lawmakers get into the details of legislation. As a result, the recommended levels of PSAS in drinking water are different because there is no one standard focus group being measured from state to state.

Water utilities have historically not made the regulation process any easier. Congress passed the Safe Drinking Water Act in 1974, which regulated many contaminants and called for a high level of purity in drinking water. But water purification is a costly process, and after a 1996 amendment to the Safe Water Act which limited the government’s oversight, activists have little faith that more reforms can be made at the federal level.

In  the absence of sufficient regulation by federal and state authorities, many people choose to take precautions into their own hands by purchasing home filter pitchers that remove contaminants.

Aquagear filter pitchers have a lifetime guarantee

Though PSAS are not a cause for outright alarm, you are right to be concerned.

At Aquagear, we take clean drinking water seriously. So seriously, in fact, that we’ve had our products evaluated by a third party lab. Independent lab testing shows that our filters meet NSF P473 requirements for the removal of 99.99% of existing PFOA and PFOS in drinking water.

Our proprietary blend of activated carbon and ion exchange media protects your family from a wider spectrum of tap water contaminants than the leading competitors. Aquagear filter pitchers also come with a lifetime guarantee. Our filter subscription service provides customers with sustainably designed, BPA-free filters every 120 gallons, which is three times longer than most competitors. Check out our product page to learn more.


Cordner, A. (2019, January 8). Guideline levels for PFOA and PFOS in drinking water: the role of scientific uncertainty, risk assessment decisions, and social factors. Journal of Exposure Science & Environmental Epidemiology.https://www.nature.com/articles/s41370-018-0099-9 

Environmental Working Group. (2018, July 30). Update: Mapping the Expanding PFAS Crisis. https://www.ewg.org/research/update-mapping-expanding-pfas-crisis 

Feldscher, K. (2016, August 9). Unsafe levels of toxic chemicals found in drinking water of 33 states. The Harvard Gazette. https://news.harvard.edu/gazette/story/2016/08/unsafe-levels-of-toxic-chemicals-found-in-drinking-water-of-33-states/ 

Felton, R. (2020, September 24). Why Dangerous 'Forever Chemicals' Are Still Allowed in America's Drinking Water. Consumer Reports. https://www.consumerreports.org/water-quality/why-dangerous-forever-chemicals-are-still-allowed-in-americas-drinking-water-a5698361954/ 

Felton, R. (2020, September 24). What’s Really in Your Bottled Water? Consumer Reports. https://www.consumerreports.org/water-quality/whats-really-in-your-bottled-water-a5361150329/ 

Leighton Paisner, B.C. (2021, June 10). State-by-State Regulation of PFAS Substances in Drinking Water. https://www.jdsupra.com/legalnews/state-by-state-regulation-of-pfas-9713957/ 

Hogue, C. (2021, July 23). California drafts safe limits for PFOA and PFOS in drinking water. Chemical & Engineering News. https://cen.acs.org/environment/persistent-pollutants/California-drafts-safe-limits-PFOA/99/web/2021/07 

United States Environmental Protection Agency (November 2017) Technical Fact Sheet – Perfluorooctane Sulfonate (PFOS) and Perfluorooctanoic Acid (PFOA). https://www.epa.gov/sites/default/files/2017-12/documents/ffrrofactsheet_contaminants_pfos_pfoa_11-20-17_508_0.pdf 

United States Environmental Protection Agency (2021, December 2). Drinking Water Health Advisories for PFOA and PFOS. https://www.epa.gov/ground-water-and-drinking-water/drinking-water-health-advisories-pfoa-and-pfos