The EPA finally acknowledged the risks of PFAS in sewage sludge. What’s next?

The Environmental Protection Agency (EPA) and state agencies promoted sludge to farmers as a sustainable, low-cost option that also helped communities deal with their new waste problem. As Sarah Alexander, executive director of the Maine Organic Farmers and Gardeners Association, recounts in our podcast episode about PFAS in sewage sludge, “farmers were really pressured into taking sludge in a lot of instances. This wasn’t something that they sought out — this was the Department of Environmental Protection. And I’ve seen the permits that they’ve issued: It says right on the permit, ‘this will not cause any water contamination. This will not cause any nuisances for your neighbors. This will not cause any contamination or issues for the soil.’”

Unfortunately, that wasn’t the case: The sludge also contained concentrated levels of PFAS, or per- and polyfluoroalkyl substances, a class of chemicals useful for greaseproofing, stainproofing, waterproofing and more. These “forever chemicals” are incredibly persistent in soil and water; they never decompose, instead circulating indefinitely in the environment, where they contaminate crops, livestock and the food that they produce. When PFAS enter the food and water supply, they cause birth defects, cancer, endocrine problems and more.

The EPA has long been aware of the potential hazards of PFAS. The New York Times reported that 3M, a PFAS manufacturer, had informed the agency about the chemicals’ presence in sludge as early as 2003. Despite these early warnings, the agency has neglected to mention PFAS as a concern at all until recently, and still recommends sludge as a sustainable fertilizer for farmers and gardeners. In January, the agency finally changed course slightly when it released a draft risk assessment for two PFAS in sewage sludge, PFOA and PFOS, marking the first official acknowledgement that some sludge could be dangerous. The assessment gives a much-needed estimate of the extent of the PFAS crisis nationwide and potentially lays the groundwork for tighter regulation of the chemicals. But its impact is ultimately uncertain given the Trump administration’s recent actions to blunt the EPA’s power.

How do PFAS end up in sewage?

PFAS tend to accumulate as they move through waste systems since they don’t decompose and aren’t being filtered out, so even as other components of waste diminish, PFAS become increasingly concentrated. That issue is compounded by a lack of clear standards when it comes to PFAS discharge in wastewater. Because PFAS are used by so many different industries, there are many ways they enter sewage systems. Manufacturers of PFAS may discharge them directly, and other manufacturers (such as paper mills) who use them in their products might send them out in their wastewater. Businesses that use chemicals like waxes, floor finishes and more are another source, as are households, through using or disposing of products containing PFAS or by laundering clothes that have been treated with them.

During wastewater treatment, those PFAS are left behind with other solids after most of the clean water has been separated out. Those segregated solids then undergo a series of heat treatments, filtering steps and processes that accelerate decomposition, thereby reducing their volume as well as removing other hazardous components, specifically pathogens and heavy metals. But the resulting sludge still contains PFAS — and it needs somewhere to go. While some is either landfilled or incinerated, most is approved for land application. Of that sludge, most is spread on farms as a form of fertilizer, with some also going to golf courses, home gardens or forests.

The EPA has long insisted that sewage sludge is safe, but scientists have lodged concerns for decades about what might be in the sludge. Even before PFAS became a concern, many scientists and farmers worried about the potential impact of pharmaceutical residues, particularly antibiotics, and how they might affect soil health or the health of animals grazing on land fertilized by sludge. As a result, sewage sludge is banned as a soil amendment under the USDA organic rules.

But when it comes to PFAS, it doesn’t really matter whether farms are currently using sewage sludge or not: Many of the farms that have already found PFAS in their soil have been organic for years. Thanks to the persistence of PFOA and PFOS in the environment, those chemicals are still causing problems even decades later. That dramatically widens the potential scope of PFAS contamination on U.S. farmland, since it’s not enough to examine land where sludge has been used recently — any land that received PFAS-contaminated sludge (at least 70 million acres, or a fifth of all farmland, per one estimate) over the last several decades could be contaminated.

What does the EPA’s new draft assessment add to our knowledge about PFAS?

The EPA’s new draft assessment set out to explore the risks that sewage sludge application poses to the food system by combining the available data on several different factors: PFAS levels in sampled sewage, how PFAS move in several different kinds of soils and waterways, and how much PFAS plants and animals take up into their tissues. By analyzing these factors together, the EPA’s draft analysis modeled different exposure scenarios — varying PFAS concentration in sewage sludge or varying consumption of certain products, for example — demonstrating that some scenarios present significant risk of unsafe PFAS exposure. These include crops coming from land that had been fertilized with sludge that was especially high in PFAS, or groundwater pulled from wells that were close to sludge-disposal sites.

Still, the EPA’s modeling does not suggest that PFAS from sludge have contaminated the food supply or groundwater on farms on a wide scale so far. Not all crops pass PFAS from the soil into their edible components, and so it’s possible for some land fertilized with contaminated sludge to produce food that’s nevertheless safe for consumption. Likewise, because of differences in site and soil permeability, not all PFAS in sludge necessarily makes it into groundwater. There’s also some safety in numbers: The foods that make up the bulk of our diets contain ingredients sourced from many different farms, meaning that PFAS-contaminated ingredients from one farm could be diluted by the inclusion of non-contaminated ingredients from other farms. (Though it’s worth noting that this safety net doesn’t apply to small farms that sell directly to consumers.) While there aren’t yet federal food safety limits for PFAS exposure, an FDA sampling of common foods supports the idea that most of the food supply is generally safe.

Notably, the draft assessment’s modeling process isn’t the same as comprehensive testing of soil and water around the country, nor does it map out risks based on historical PFAS application. Even if most farms can reasonably expect to have soil and water PFAS concentrations that are below levels of concern, the draft assessment does indicate that many farms around the country are likely to have high PFAS levels, thanks to abnormally concentrated sludge or certain site-based factors. On an individual farm level, the agency still recommends testing ground water to ensure that PFAS levels are below exposure limits and using that data as a starting point for further investigation. Such inquiries are existential: As we’ve explored in our podcast, What You’re Eating, as well as our FoodPrint of PFAS report, farmers who discover high levels of PFAS often risk losing everything.

What’s next for PFAS regulations?

The EPA’s draft assessment outlines potential future actions for mitigating the risk of agricultural PFAS contamination; most of these focus on reducing the amount of PFAS that enters wastewater. Many local wastewater treatment plants around the country have already reduced their PFAS loads by requiring companies to pretreat their own wastewater. In the future, the EPA could impose these standards nationwide, and advocates say the draft guidance is an important step toward more comprehensive regulations.

But what the agency will actually implement is uncertain considering the recent actions of the Trump administration. Despite pledges from the EPA’s new administrator, Lee Zeldin, to make PFAS a top priority, the administration withdrew a new rule that would have limited the chemicals’ discharge from PFAS manufacturers just before it was set to take effect. Though that rule would have applied to only a small number of facilities, it’s unlikely that the administration would consider more sweeping regulations given their track record of muzzling the EPA to “promoting economic growth for families across the country” at the cost of environmental regulations.

Although the administration can easily derail policies within the EPA, they would have substantial difficulty discarding a more explicit mandate from Congress to address the PFAS crisis. And that’s something farm and food safety advocates around the country have insisted is needed: Documents like the new draft regulation don’t provide a comprehensive plan to slow PFAS production and remediate contaminated soil or water supplies. Those provisions, along with related funding — to test farm soils nationwide, expand food monitoring or provide farmers with support and options if they find PFAS in their soil or water — have all featured in previously introduced PFAS legislation. So far, however, those bills have failed to progress through a gridlocked Congress.

That means the brunt of new PFAS action is likely to fall to state and local governments for the time being. Many states have adopted or introduced legislation to ban the manufacture and sale of PFAS, and several already have policies designed to help limit PFAS in drinking water. And while these laws don’t technically have jurisdiction over the entire country, their adoption in states with giant consumer markets, like California, may nudge manufacturers to think twice about using PFAS. That incentive, paired with the billions in financial liability PFAS manufacturers are facing in contamination suits nationwide, could apply pressure to reduce new PFAS production even as federal policy lags.