New PFAS guidelines – a water quality scientist explains technology and investment needed to get forever chemicals out of US drinking water

PFAS can be found in hundreds of water systems in the U.S. d3sign/Moment via Getty Images

by Joe Charbonnet, Iowa State University

Harmful chemicals known as PFAS can be found in everything from children’s clothes to soil to drinking water, and regulating these chemicals has been a goal of public and environmental health researchers for years. On March 14, 2023, the U.S. Environmental Protection Agency proposed what would be the first set of federal guidelines regulating levels of PFAS in drinking water. The guidelines will be open to public comment for 60 days before being finalized.

Joe Charbonnet is an environmental engineer at Iowa State University who develops techniques to remove contaminants like PFAS from water. He explains what the proposed guidelines would require, how water utilities could meet these requirements and how much it might cost to get these so-called forever chemicals out of U.S. drinking water.

1. What do the new guidelines say?

PFAS are associated with a variety of health issues and have been a focus of environmental and public health researchers. There are thousands of members of this class of chemicals, and this proposed regulation would set the allowable limits in drinking water for six of them.

Two of the six chemicals – PFOA and PFOS – are no longer produced in large quantities, but they remain common in the environment because they were so widely used and break down extremely slowly. The new guidelines would allow for no more than four parts per trillion of PFOA or PFOS in drinking water.

Four other PFAS – GenX, PFBS, PFNA and PFHxS – would be regulated as well, although with higher limits. These chemicals are common replacements for PFOA and PFOS and are their close chemical cousins. Because of their similarity, they cause harm to human and environmental health in much the same way as legacy PFAS.

A few states have already established their own limits on levels of PFAS in drinking water, but these new guidelines, if enacted, would be the first legally enforceable federal limits and would affect the entire U.S.

A water droplet sitting on a piece of fabric.
Chemicals used to create water-repellent fabrics and nonstick pans often contain PFAS and leak those chemicals into the environment. Brocken Inaglory/Wikimedia Commons, CC BY-SA

2. How many utilities will need to make changes?

PFAS are harmful even at extremely low levels, and the proposed limits reflect that fact. The allowable concentrations would be comparable to a few grains of salt in an Olympic-size swimming pool. Hundreds of utilities all across the U.S. have levels of PFAS above the proposed limits in their water supplies and would need to make changes to meet these standards.

While many areas have been tested for PFAS in the past, many systems have not, so health officials don’t know precisely how many water systems would be affected. A recent study used existing data to estimate that about 40% of municipal drinking water supplies may exceed the proposed concentration limits.

3. What can utilities do to meet the guidelines?

There are two major technologies that most utilities consider for removing PFAS from drinking water: activated carbon or ion exchange systems.

A membrane treatment system.
Water treatment systems can use activated carbon or ion exchange to remove PFAS from drinking water. Paola Giannoni/E+ via Getty Images

Activated carbon is a charcoal-like substance that PFAS stick to quite well and can be used to remove PFAS from water. In 2006, the town of Oakdale, Minnesota, added an activated carbon treatment step to its water system. Not only did this additional water treatment bring PFAS levels down substantially, there were significant improvements in birth weight and the number of full-term pregnancies in that community after the change.

Ion exchange systems work by flowing water over charged particles that can remove PFAS. Ion exchange systems are typically even better at lowering PFAS concentrations than activated carbon systems, but they are also more expensive.

Another option available to some cities is simply finding alternative water sources that are less contaminated. While this is a wonderful, low-cost means of lowering contamination, it points to a major disparity in environmental justice; more rural and less well-resourced utilities are unlikely to have this option.

4. Is such a major transition feasible?

By law, the EPA must consider not just human health but also the feasibility of treatment and the potential financial cost when setting maximum contaminant levels in drinking water. While the proposed limits are certainly attainable for many water utilities, the costs will be high.

The federal government has made available billions of dollars in funding for treating water. But some estimates put the total cost of meeting the proposed regulations for the entire country at around US$400 billion – much more than the available funding. Some municipalities may seek financial help for treatment from nearby polluters, while others may raise water rates to cover the costs.

5. What happens next?

The EPA has set a 60-day period for public comment on the proposed regulations, after which it can finalize the guidelines. But many experts expect the EPA to face a number of legal challenges. Time will tell what the final version of the regulations may look like.

This regulation is intended to keep the U.S. in the enviable position of having some of the highest-quality drinking water in the world. As researchers and health officials learn more about new chemical threats, it is important to ensure that every resident has access to clean and affordable tap water.

While these six PFAS certainly pose threats to health that merit regulation, there are thousands of PFAS that likely have very similar impacts on human health. Rather than playing chemical whack-a-mole by regulating one PFAS at a time, there is a growing consensus among researchers and public health officials that PFAS should be regulated as a class of chemicals.

Joe Charbonnet, Assistant Professor of Environmental Engineering, Iowa State University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Public health vs. economic growth: Toxic chemical rules pose test for Biden

Read the full story in the New York Times.

The Biden administration is preparing to impose some of the first new rules in a generation to restrict or ban an array of toxic chemicals that are widely used in manufacturing, presenting the White House with tough choices between its economic agenda and public health.

Many of the substances in question are important to industries that President Biden has backed through other policies intended to bolster global competitiveness and national security, such as semiconductors and electric vehicles.

Corporations are framing the decisions about new regulations for an initial group of toxic chemicals as putting at risk the administration’s drive to nurture the American economy of the future. Environmental and public health groups are stressing the need to focus on protecting workers and communities from substances known to carry health risks, such as cancer, liver and kidney damage and infertility.

A major lobbying clash is already underway. Chip makers, the burgeoning electric vehicle industry and other companies, including military contractors, are pressuring the administration to water down the new rules, saying the repercussions of a ban or new restrictions could be crippling.

Webinar: The ESG Landscape and Contextualizing it for the Great Lakes Region

Apr 20, 2023, 10 am CDT
Register here.

The ESG movement is indicative of a fundamental shift in the global economy. Companies that develop a thoughtful approach to Environmental, Social and Governance (ESG) performance to help manage risks and build resilience have an opportunity for competitive advantage and improved long-term performance, benefiting their business but also the region(s) in which they operate. ESG reporting and disclosure is a quickly evolving space and will have implications for public and private companies operating in the Great Lakes region. 

Public companies will be increasingly exposed to new reporting standards and mandatory disclosure regulations focused on consistent and comparable disclosure for investors. This will eventually include Scope 3 GHG emissions, which extends into the supply chains of organizations. Private companies with large publicly traded customers will face growing pressure to report their GHG emissions to customers so they can fulfil these disclosure obligations. 

These efforts do not happen overnight, and a significant amount of change management is required to effectively navigate this new territory.

The webinar, sponsored by the Council of Great Lakes States, will feature Sarah Keyes, CEO of ESG Global Advisors, who will address the important topic of ESG in business and contextualize it for the Great Lakes region. She’ll answer questions such as:

  • What is ESG and how does it differ from CSR?
  • Why is ESG important for the Great Lakes region? what do businesses need to know?
  • How do businesses get started with integrating ESG into their management?

During the webinar, Sarah will also take questions from the audience and share examples of good practice.

EPA announces accelerated action on four organophosphate pesticides based on updated exposure assessments

The U.S. Environmental Protection Agency (EPA) has announced an effort to expedite protections on some high-risk uses of four organophosphate pesticides. The Agency is releasing the updated occupational and non-occupational spray drift exposure risk assessments for these four pesticides – diazinon, ethoprop, tribufos and phosmet – several years ahead of the scheduled completion of EPA’s work on these chemicals in order to seek early mitigation prior to completing the standard registration review process.

Diazinon, ethoprop, tribufos and phosmet are part of the group of pesticides known as organophosphates. These pesticides are used in both agricultural (e.g., fruit and nut trees, vegetables and herbs, cotton) and non-agricultural settings for a range of purposes. Diazinon and phosmet controls insects, ethoprop controls worms and other soil pests, and tribufos defoliates cotton prior to harvest. These pesticides are currently undergoing registration review, a process that requires EPA to reevaluate pesticides every 15 years to ensure that as the ability to assess risk evolves and as policies and practices change, pesticides continue to meet the statutory standard of causing no unreasonable adverse effects on human health or the environment.

As part of the registration review process, EPA assessed the potential risks to people who mix, load, and apply the four pesticides, farmworkers who work with crops that have been treated with these pesticides, and bystanders who are potentially exposed to spray drift, including families living in agricultural communities.

The Agency identified the following potential risks for each pesticide:

  • The diazinon assessment identified potential risks to workers who mix, load, and apply the pesticide, and to bystanders (including farmworkers) who could be exposed to spray drift.
  • The ethoprop assessment identified potential risks to workers who mix, load, and apply the pesticide, and to bystanders (including farmworkers) who could be exposed to spray drift.
  • The phosmet assessment identified potential risks to workers who mix, load, and apply the pesticide, workers conducting certain post-application activities (e.g., weeding, hand harvesting, or workers re-entering treated areas), and bystanders (including farmworkers) who may be exposed to spray drift. 
  • The tribufos assessment identified potential risks to workers who mix, load, and apply the pesticide, and to bystanders (including farmworkers) who may be exposed to spray drift.

Although registration review for these pesticides was not scheduled to be completed until 2025-2026, after recognizing that several of uses of these four pesticides present significant human health risks, EPA is taking accelerated and early action to address these risks. This will allow the Agency to put important protections in place quickly for some high-risk uses of these pesticides, while allowing time to work through the complicated scientific issues that need to be addressed before completing registration review.

EPA is currently meeting with the technical registrants of the four pesticides about early risk mitigation. The types of mitigation under consideration include cancellation of uses and formulation types, prohibition of application methods, increased personal protective equipment for pesticide handlers, spray drift requirements, and new restrictions on when workers can reenter treated fields and perform harvesting and other types of post-application activities. The Agency is asking the registrants to submit label amendments that reflect the necessary risk mitigation measures for each of these four organophosphates and is prepared to expedite label reviews in order to implement the protections as quickly as possible.

The updated exposure risk assessments are now available in the registration review dockets, EPA-HQ-OPP-2008-0351 (diazinon), EPA-HQ-OPP-2008-0560 (ethoprop), EPA-HQ-OPP-2008-0883 (tribufos) and EPA-HQ-OPP-2009-0316 (phosmet) at

Given the expedited nature of this effort, the Agency is not taking comment on these assessments. Stakeholders will have an opportunity to comment on the four occupational and non-occupational spray drift risk assessments when the cases progress through the next step of registration review with the proposed interim decision, which will include the full updated human health risk assessment for each. EPA expects to issue the proposed interim decisions in fiscal year 2025 (tribufos) and fiscal year 2026 (ethoprop, diazinon and phosmet).

New report shows environmental impact of cigarette waste

Read the full story at Waste360.

A new report by the National Institute of Cancer Prevention and Research (NICPR) has found that tobacco waste is a major environmental hazard in India, with millions of cigarette butts and other tobacco products being discarded every day.

Urban landfills and the circular economy

Read the full story at Waste360.

In our latest episode of NothingWasted!, we bring you a dynamic session from Waste360 Sustainability Talks — Urban Landfills and the Circular Economy. The discussion focused on addressing the challenges of increasing global waste; specifically, the growth due to urban populations and consumer culture—and how the shift to a circular economy can increase sustainability.

Chicken and salmon have equivalent—and surprisingly far-reaching—environmental impacts

Read the full story at Anthropocene Magazine.

Many people choose fish instead of meat to offset their environmental footprints. But if the choice is farmed salmon instead of chicken, then researchers have some unsettling results to share: the environmental impact of these two foods is about the same.

The reason for that is their feed, which is remarkably similar for chicken and salmon, and accounts for the majority of impacts—which are spread across land and sea for both animals.

Clever orchard design for more nuts

Read the full story from the University of Göttingen.

To reduce biodiversity loss in agricultural landscapes, more sustainable and environmentally friendly agricultural practices are needed. A research team has investigated how ecosystem services such as pollination could be improved in macadamia plantations. The scientists showed that a certain design of plantations — for instance, how the rows of trees are arranged, the varieties, and the integration of semi-natural habitats in and around the plantations — can increase the pollination performance of bees.

New research reveals 12 ways aquaculture can benefit the environment

Read the full story from the University of Melbourne.

Aquaculture, or the farming of aquatic plants and animals, contributes to biodiversity and habitat loss in freshwater and marine ecosystems globally, but when used wisely, it can also be part of the solution, new research shows.

Restricting antibiotics for livestock could limit spread of antibiotic-resistant infections in people

Read the full story from the University of Washington.

A new study shows that a 2018 California bill banning routine antibiotic use in livestock is linked with reduction in some antibiotic-resistant infections.