For the first time, the Environmental Protection Agency has warned that “permanent chemicals” present in sewage sludge used as fertilizer could pose risks to human health, and a study released Tuesday said the risks may outweigh the agency's safety in some cases. thresholds “sometimes by several orders of magnitude.” However, the agency said that the general food supply is not at risk.
A growing body of research shows that sludge can be contaminated with man-made chemicals known as per- and polyfluoroalkyl substances, or PFASs, which are widely used in everyday items like non-stick cookware and stain-resistant carpets. Contains chemicals associated with a number of diseases do not break down in the environment, including increasing the risk of cancer, and contaminated sludge can contaminate soil, groundwater, crops and livestock when used as fertilizer on agricultural land.
last year, The New York Times reported on this 3M, which has manufactured PFAS for decades, discovered in 2000 that the chemicals were found in sludge samples from municipal wastewater plants across the country. In 2003, 3M reported its findings to the EPA.
For decades, the EPA has encouraged the use of sludge from treated wastewater as a cheap fertilizer with no limits on how much PFAS it can contain. But the agency's new draft risk assessment sets a potential new course. If finalized, it could mark what could be the first step toward regulating PFAS in sludge used as fertilizer, which the industry calls biosolids. The agency currently regulates certain heavy metals and pathogens in sewage sludge used as fertilizer, but not PFAS.
The Biden administration has tackled PFAS contamination elsewhere, imposing limits on PFAS in drinking water for the first time and designation of two types of PFAS as hazardous under the nation's Superfund cleanup law. The rules came after the agency said in 2023 that there are no safe exposure levels to these two PFASs.
EPA Acting Administrator Jane Nishida said in a statement that the new EPA assessment “provides important data to inform future actions by federal and state agencies, as well as wastewater treatment plants and farmers, to protect people from exposure to PFAS.”
It is not clear what further steps the incoming Trump administration will take. President-elect Trump is hostile to regulations; However, he has talked about campaigning to “remove dangerous chemicals from our environment” and concerns about PFAS contamination in fertilizer have reached some deep red states.
Here comes the EPA's risk study Farmers across the country are discovering PFAS in their own land.
In Maine, the first and only state to systematically test farmland for PFAS, dozens of dairy farms were found to be contaminated. A group of farmers in Texas sued a sludge fertilizer provider last year after a neighboring farm used the fertilizer on their fields. County investigators found several types of PFAS in farmers' soil, water, crops and livestock, and farmers have since sued the EPA, accusing the agency of failing to regulate PFAS in biosolids. In Michigan, state officials shut down a farm after tests revealed particularly high concentrations in the soil and cattle grazing on the soil.
The EPA said its analysis did not show that the general food supply was at risk. Sewage sludge is applied to less than 1 percent of the fertilized acres of agricultural land per year, he said, a figure roughly in line with industry data. And not all farms using sewage manure pose a risk.
Still, studies have found that because PFAS are so persistent in the environment, contaminated sludge applied years or even decades ago may continue to be a source of contamination. More than 2 million tons were used dry according to the biosolids industry, in 2018, 4.6 million hectares of agricultural land. Farmers have received permits to use sewage sludge on about 70 million acres, or about one-fifth of all U.S. farmland, the industry says.
EPA has not changed its policy of promoting sludge fertilizer, which has benefits as well as risks. It is rich in nutrients, and spreading it on fields reduces the need to burn it or throw it in landfills, which incur other environmental costs. Using sludge fertilizer also reduces the use of synthetic fertilizers based on fossil fuels.
The agency said in a new assessment that the highest human risks at farms using contaminated sludge are drinking milk from contaminated farm pasture cows, drinking contaminated water, and eating eggs from pasture-raised chickens or beef from cattle. bred from eating fish in contaminated soil or from runoff-contaminated lakes and ponds.
Especially at-risk households living near or products purchased from a contaminated source, such as milk or beef from a family farm contaminated with PFAS from sewage sludge– the agency said. Under certain conditions, he said, the risks exceed the EPA's acceptable limits by several orders of magnitude.
The general public, which is more likely to buy milk from a grocery store that sources its product from multiple farms, is at lower risk, the agency said. For its evaluation, the EPA focused on two of the most commonly detected perennial chemicals called PFOA and PFOS, though there are many others.
The Food and Drug Administration does not set limits on PFAS levels in food. Since 2019, there is an agency He tested about 1300 samples and said the vast majority are free of the types of PFAS the agency can test for.
There are some public health professionals and advocacy groups questioned the test methodologyand the agency itself says, “Food exposure to PFAS is a new area of science and there is still much we don't know.” Last year, Consumer Reports said it found PFAS in some milkincluding organic brands. Packaging is another source of PFAS in food.
The National Association of Clean Water Agencies, which represents wastewater treatment facilities across the country, said the findings reinforce that sludge fertilizer is not a risk to the public food supply. Mud purveyors argued that they had should not be responsible It says the chemicals for PFAS contamination are simply passing through them.
“Ultimately, manufacturers of these chemicals must bear the responsibility and cost of removing these chemicals from their products and the environment,” said Adam Krantz, the group's chief executive.
In the absence of federal measures, states began to take their own measures. Maine banned the use of sewage sludge on agricultural land in 2022 and remains the only state to do so. In December A Texas lawmaker has introduced a bill it would set limits on the levels of certain types of PFAS in sewage sludge applied to farmland. Oklahoma lawmakers also filed a bill imposing a moratorium on the use of sludge on agricultural land.
A complete ban on the use of sludge as fertilizer would bring its own problems. Sewage sludge still needs a place to go. Since Maine's ban, some wastewater treatment plants say they have been forced to move sewage sludge out of state.
Environmental experts say the key is to limit the amount of PFAS that ends up in wastewater and sewage in the first place. This could come from phasing out PFAS use in everyday products or requiring manufacturers to treat contaminated wastewater before sending it to municipal wastewater treatment facilities.