Understanding the EPA's proposed regulations of 'forever chemicals' in water systems

The U.S. Environmental Protection Agency last week announced the first-ever regulations that would limit chemicals known as PFAS, or "forever chemicals," in drinking water. The proposed regulation would require public water systems to monitor for these chemicals, share results with the public, and reduce PFAS contamination if levels exceed the proposed regulatory standards.

Known as forever chemicals because they degrade extremely slowly in the environment, per- and polyfluoroalkyl substances, commonly known as PFAS, are a group of synthetic organic contaminants used in a variety of industrial processes and consumer products, including non-stick cookware, food wrappers, water-resistant clothing, and textiles. When these products are used, discarded, or improperly dumped, PFAS leach into drinking water supplies. Once there, they are very difficult to remove, and they do not break down on their own because of their extremely strong chemical bonds.

Image caption: Carsten Prasse

Long-term, low-concentration exposure to PFAS can hamper the immune system, interfere with hormones, and reduce the effectiveness of vaccines. It can also cause low birth weight and high cholesterol. High doses of PFAS increase the risk for kidney cancer, liver damage, testicular cancer, and thyroid disease.

The proposal will be open for public comment for several months before it's finalized by the EPA. There is about $12 billion in federal funding available to municipalities to help mitigate PFAS and other contaminants through the Bipartisan Infrastructure Law.

The Hub sat down with Carsten Prasse, assistant professor of environmental health and engineering in the Whiting School of Engineering and the Bloomberg School of Public Health, to discuss the proposed regulation and its possible impacts on the nation's water supply.

How present are PFAS in the country's drinking water supply?

Unfortunately, they are very widely present. The current estimate is that 200 million Americans have PFAS in their drinking water. In addition to individuals who get their water from a utility, a study conducted by the U.S. Geological Survey has also shown that approximately 20% of private wells are contaminated with PFAS.

It's very difficult to remove PFAS from water. How are municipalities going to comply with the mitigation requirements outlined in this regulation?

There are a few technologies that can be used. These include reverse osmosis, activated carbon, and ion-exchange resins. The main challenge associated with these technologies is the cost. Reverse osmosis is pretty energy-intensive, as the water must be pushed through membranes. Activated carbon and ion exchange resins are also costly and must be replaced on a regular basis when their sorption capacity, meaning their capacity to bind PFAS, is exhausted. A related challenge is to determine when this replacement must happen. To do this accurately, the water must be tested regularly, which adds costs. The cost will be a big issue for all utilities but mostly for small water systems, as the expense will be divided among fewer households—and most water systems in the United States are small. The situation is even worse for people who have their own well.

This proposed regulation puts the onus on municipalities to address PFAS. What other steps should be taken to combat forever chemicals in our environment?

Personally, I think it is unfair to put all the burden on municipalities. The financial burden will be particularly high for small utilities and people using private wells. It is important to keep in mind that the people who have to deal with PFAS in their drinking water are generally not the ones who caused the contamination. I think there are a lot of environmental justice issues that need to be addressed when considering who is exposed to these contaminants. But more generally, I think the most important step would be to stop the production of these chemicals and ideally also take products that contain PFAS off the market. Unfortunately, I don't think this is going to happen anytime soon, considering how widely they are used. Stopping the use of fire-fighting foams that contain PFAS, which are a major contributor to PFAS contamination in the environment, would be an important step. In addition, we also need to think about what can be done in our wastewater treatment plants to avoid the release of PFAS present in municipal and industrial wastewater into the environment.

What can consumers do to reduce their exposure to forever chemicals?

This is actually a pretty challenging task, as PFAS are present in so many products that we use in our daily lives. This includes non-stick cookware, water resistant clothing, cosmetics, toilet paper, menstrual products, dental floss, anti-stain treatments for carpets, clothing, and more. I recommend only buying these products if the packaging explicitly states that they are free of PFAS. Other exposures such as those from food packaging or food are more difficult to avoid. Hopefully the regulation will also lead to more pressure on the industry to use PFAS-free alternatives. With respect to reducing PFAS exposure in drinking water, bottled water, especially if in plastic bottles, isn't necessarily a better alternative due to the exposure to other chemicals such as plasticizers that are leaching out of the plastic. Moreover, many bottled water sources are municipal utility supplies that may be contaminated, and bottled water has not been regulated for PFAS in the past.

What else should people know about these chemicals?

The main thing for people to know is that there are thousands of different PFAS, while the proposed regulation focuses only on six. While this regulation is a great first step, there is a lot more work that needs to be done. We have seen many cases where the regulation of individual chemicals has resulted in the shift to other chemicals that have very similar structures and properties and thus also similar toxicities. We have seen this play out for PFAS in the past: Hexafluoropropylene oxide dimer acid, also known as GenX, is considered a replacement for perfluorooctanoic acid, and perfluorobutane sulfonic acid, or PFBS, is considered a replacement for perfluorooctane sulfonic acid. Luckily, the new regulation includes both GenX and PFBS, which is a step in the right direction to prevent the industry from simply using other PFAS that are currently not regulated.