‘Forever chemicals’ were found in MWRA fertilizer. Here’s what to know.

A pipe reads "digested sludge" at the MWRA's waste-water treatment plant in Quincy. David Abel/Globe Staff

For decades, the Massachusetts Water Resources Authority has been turning waste into a commodity.

At the agency’s Quincy plant, the MWRA collects sludgy waste water from across the region and transforms it into fertilizer pellets, that are in turn sold or provided back to communities for use in parks, farms, gardens, and golf courses.

But tests this year have ignited concern over the fertilizer, The Boston Globe reports.

Results show man-made chemicals known commonly as PFAS — or per- and polyfluoroalkyl substances — have been detected in the fertilizer — chemicals that have been linked to low infant birth weights, increased cancer risk, and immune system changes, among other health effects, according to the newspaper.


Dubbed “forever chemicals,” PFAS do not fully degrade over time when they enter the environment.

Here’s what to know:

What are PFAS?

PFAS are “a group of man-made chemicals that includes PFOA, PFOS, GenX, and many other chemicals,” according to the federal Environmental Protection Agency.

Since the 1940s, they’ve been used in several industries and can be found in many common, everyday products.

“They have been used in non-stick cookware, water-repellent clothing, stain resistant fabrics and carpets, some cosmetics, some firefighting foams, and products that resist grease, water, and oil,” the Agency for Toxic Substances and Disease Registry says on its website.

According to ATSDR, PFAS can integrate into water, soil, and air, where they remain. PFAS can build up in animals and humans who are repeatedly exposed to the chemicals over time.

So what does this mean for health impacts?

Several agencies say while more research is needed, studies indicate exposure to elevated levels could pose problems and complications.

PFOA and PFOS are among the most-researched PFAS, the EPA says. Studies of those chemicals have shown they can cause “reproductive and developmental, liver and kidney, and immunological effects in laboratory animals.”

“Studies indicate that exposure to sufficiently elevated levels of certain PFAS may cause a variety of health effects including developmental effects in fetuses and infants, effects on the thyroid, liver, kidneys, certain hormones and the immune system,” the Massachusetts Department of Environmental Protection says. “Some studies suggest a cancer risk may also exist in people exposed to higher levels of some PFAS. Scientists and regulators are still working to study and better understand the health risks posed by exposures to PFAS, and MassDEP is following developments in this burgeoning area closely.”


PFAS-contaminated drinking water has garnered more national and local attention in recent years, according to MassDEP, which requires public water suppliers to test new water sources for PFAS.

According to the Globe, the EPA recommends towns and cities notify the public if two detected chemicals total 70 parts per trillion — a metric MassDEP also uses for five PFAS.

New research shows, however, that smaller amounts of PFAS can be toxic — findings that have triggered federal and state agencies to review their standards, the newspaper reports.

In Massachusetts, regulators are slated to lower ground water and drinking water standards to a 20 parts-per-trillion limit for six combined chemicals, according to the Globe.

But when it comes to fertilizer, both federal and Massachusetts officials do not have any set standards.

What the MWRA said about the tests

The MWRA tested its fertilizer in March, showing the product held over 18,000 parts per trillion of three PFAS.

Ria Convery, an agency spokeswoman, told the Globe that MWRA products comply with current regulations.

“In the absence of existing state or federal standards for PFAS in biosolids, the Commonwealth, through the Department of Environmental Protection, will begin developing testing protocols and screening levels for biosolids and continuing to require entities that sell, distribute, and apply biosolid products to test for PFAS,” Convery said in a statement. “Recognizing the emerging issue of PFAS contamination and the importance of ensuring public health, the MWRA will continue to test biosolid pellets for PFAS chemicals, while meeting all state and federal requirements for waste-water contaminants.”


MWRA officials declined to discuss whether they should still sell the fertilizer, according to the newspaper. In the last three years, the MWRA has sold over 100,000 tons in bulk sales and 1,300 tons in other sales, such as to individuals, the Globe reports.

Convery said the MWRA does not profit from its fertilizer sales, adding that the goal is “beneficial reuse of the disposed waste.”

The test came following new standards for fertilizer in Maine earlier this year after an Arundel dairy farm was found with elevated levels of PFAS, the Globe reports, adding that the test probed for three PFAS out of thousands. The agency has and continues to test for heavy metals and pathogens as required under federal regulations.

Dave Deegan, a spokesperson for the EPA’s New England office, told the newspaper that the agency is studying PFAS in biosolids, like fertilizer. The EPA did not speak specifically to the MWRA test results.

“Addressing the uncertainty around potential risk for pollutants identified in biosolids is a top priority,” Deegan said. “The agency will also be taking steps very soon to bolster research efforts related to PFAS in biosolids.”

What experts said about the findings

According to the Globe, research on PFAS is still being conducted to determine whether crops grown in contaminated fertilizer are hazardous to eat — a finding that potentially varies based on the amount of fertilizer used and the soil type.

“I wouldn’t want to use the more highly contaminated samples,” said toxicologist Linda Birnbaum, who formerly served as director of the National Institute for Environmental Health Sciences.


Linda Lee, an environmental chemist at Purdue University, said, however, that reusing waste-water sludge is better than burning it or dumping it in landfills, the Globe reports. She said PFAS should no longer be used in consumer products but didn’t think the fertilizers should be prohibited at the moment.

“These compounds are persistent, and they can cause adverse effects,” she said. “But we should also be concerned about the unintended consequences of overreacting.”

Health and environmental advocates disagree, and point to the fact that the EPA’s inspector general also, in 2018, recognized the need to further study the issue, according to the newspaper.

Kyla Bennett, science policy director of the advocacy group, Public Employees for Environmental Responsibility, told the Globe it “defies logic” that Massachusetts acknowledged health risks with PFAS while still selling the fertilizer.

“We need to pause and figure out a better answer,” Bennett said.


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