The Environmental Protection Agency on Tuesday warned for the first time that “permanent chemicals” present in sewage sludge used as fertilizer could pose a risk to human health.
The agency said in an extensive review that while the general food supply is not threatened, the risks from contaminated fertilizer could exceed EPA safety standards by “some orders of magnitude in some cases.” Ta.
A series of studies has shown that the sludge may be contaminated with man-made chemicals known as per- or polyfluoroalkyl substances (PFAS), which are widely used in everyday products such as nonstick cookware and stain-resistant carpets. It has been shown that there is a sex. Chemicals associated with various diseases, including increased risk of cancer, do not break down in the environment, and when contaminated sludge is used as fertilizer on agricultural land, it can contaminate soil, groundwater, crops, and livestock. there is.
Last year, the New York Times reported that 3M, which has been manufacturing PFAS for decades, discovered in 2000 that the chemicals were being detected in sludge samples from municipal wastewater treatment plants across the United States. In 2003, 3M communicated its findings to the EPA.
For decades, the EPA has encouraged the use of sludge from treated wastewater as an inexpensive fertilizer without setting limits on PFAS content. But the agency's new draft risk assessment could point in a new direction. If finalized, it could be the first step toward regulating PFAS in sludge (known in the industry as biosolids) used as fertilizer. The agency currently regulates certain heavy metals and pathogens in sewage sludge used as fertilizer, but not PFAS.
The Biden administration has also tackled PFAS contamination elsewhere, placing limits on PFAS in drinking water for the first time and designating two types of PFAS as hazardous under the nation's Superfund cleanup law. These rules were enacted after the agency announced that there is no safe level of exposure to these two PFAS in 2023.
EPA Acting Administrator Jane Nishida said in a statement that the new EPA assessment is an important study that will “inform future actions by federal and state agencies,” as well as wastewater treatment plants and farmers, “to protect people from PFAS exposure.” We will provide information.” .
It is unclear what further measures the incoming Trump administration will take. Although President-elect Trump campaigned on the campaign to “remove dangerous chemicals from the environment,” he has been hostile to regulation, and concerns about PFAS contamination in fertilizer have reached some serious states. .
EPA's risk study comes as farmers across the country are discovering PFAS on their land.
In Maine, the first and only state to systematically test farmland for PFAS, dozens of dairy farms were found to be contaminated. In Texas, a group of ranchers last year sued a sludge fertilizer provider after neighboring farms used the fertilizer on their fields. County investigators found several types of PFAS in the ranchers' soil, water, crops, and livestock, and the ranchers subsequently sued the EPA, accusing it of failing to regulate PFAS in biosolids. In Michigan, state officials shut down a farm where tests found particularly high concentrations in the soil and in the cattle grazing on the land.
EPA said its analysis does not suggest the general food supply is at risk. The report said sewage sludge is applied to less than 1 percent of fertilized agricultural land annually, a figure that is broadly in line with industry data. Also, not all farms where sewage fertilizers are used are at risk.
Still, studies have shown that PFAS are so persistent in the environment that contaminated sludge that was applied years or even decades ago can continue to be a source of contamination. According to the biosolids industry, more than 2 million dry tons were used on 4.6 million acres of agricultural land in 2018. Farmers have permits to use sewage sludge on nearly 70 million acres, about one-fifth of all U.S. farmland, according to the industry.
EPA remains committed to promoting sludge fertilizers, which have both risks and benefits. It is rich in nutrients and, when spread on fields, reduces the need for incineration and landfilling, which have other environmental costs. Using sludge fertilizers also reduces the use of fossil fuel-based synthetic fertilizers.
In the new assessment, the agency found that farms that used contaminated sludge were allowed to drink milk from pasture-raised cows raised on contaminated farms, drink contaminated water, and use eggs from pasture-raised chickens and cows raised on pasture-raised farms. Eating beef is the highest human risk, he said. They are raised on contaminated land or by feeding on fish from lakes and ponds contaminated with runoff.
Particularly at risk are those who live near or rely on products from contaminated sources, such as milk or beef from family farms contaminated with PFAS from sewage sludge. a household, authorities said. In certain situations, the risk exceeds the EPA's acceptable standards by several orders of magnitude, he said.
The general public, who is more likely to buy milk from grocery stores that source produce from many farms, is at lower risk, officials said. In its assessment, EPA focused on the two most commonly detected permanent chemicals called PFOA and PFOS, but there are many others.
The Food and Drug Administration does not set limits on PFAS levels in foods. But since 2019, the agency tested nearly 1,300 samples and said the majority did not contain the types of PFAS that the agency could test for.
Some public health experts and advocacy groups have questioned the testing methods, and the agency itself has said that “PFAS exposure from food is an emerging field of science, and there is much we still don't know.” Last year, Consumer Reports announced that PFAS had been detected in some milk, including organic brands. Packaging is another source of PFAS in food.
The National Association of Clean Water Agencies, which represents wastewater treatment plants across the country, said the findings confirm that sludge fertilizer poses no risk to the public food supply. Sludge providers say they are not responsible for the PFAS contamination, saying the chemicals were simply washed into the sludge.
“Ultimately, the manufacturers of these chemicals will have to bear the responsibility and cost of removing them from their products and the environment,” said Adam Krantz, the group's chief executive. ” he said.
In the absence of federal action, states are beginning to take their own steps. Maine banned the use of sewage sludge on agricultural land in 2022 and is currently the only state to do so. In December, Texas lawmakers introduced a bill that would set limits on the levels of certain types of PFAS in sewage sludge applied to agricultural fields. Oklahoma lawmakers also introduced a bill that would put a moratorium on the use of sludge on agricultural land.
A complete ban on the use of sludge as fertilizer would create its own problems. Sewage sludge still needs to go somewhere. Since Maine's ban, some wastewater treatment plants say they have been forced to ship sewage sludge out of state.
Environmental experts say the key is to limit the amount of PFAS released into wastewater and sewage in the first place. That could come by phasing out the use of PFAS in everyday products or requiring manufacturers to treat contaminated wastewater before sending it to municipal wastewater treatment plants.
