Known as “forever chemicals,” perfluoroalkyl and polyfluoroalkyl substances (PFAS) can take more than 1,000 years to break down in the environment. Exposure to these chemicals has been linked to increased levels of cancer, reproductive issues and more.

While governments grapple with how to reduce the problem — the state of Maine banned land application of biosolids, and the EPA released a risk assessment acknowledging the potential health risks — researchers in New York and nationally are hunting for ways to degrade and destroy them and make testing more accessible. 

Johannes Lehmann gives a tour of Spruce Haven Dairy farm. (Emily Kenny/Spectrum News 1)

Michelle Crimi, a professor of environmental engineering at Clarkson University, has researched PFAS for about 10 years and is part of a team studying PFAS destructive treatment technologies, focusing on wastewater treatment plants that she says pose unique challenges.

“The more complex the matrix, the more difficult it is to treat it because like any chemical or physical process, the easiest to [destroy] are going to go away first and PFAS is going to fall somewhere in that spectrum. It takes more energy, and it takes more time but we’re learning more and more that it’s doable,” Crimi said.  

Additionally, Crimi’s team at Clarkson University has studied how PFAS can be removed from biosolids – the semi-solid product that comes from wastewater treatment plants. 

Angel French, the chief operating officer at the Watertown wastewater treatment plant said they have only gotten positive feedback from farmers who use their biosolids. The plant takes in 10 million gallons of water per day and produces 4,000 wet tons of biosolids every year. (Emily Kenny/Spectrum News 1)

“The idea of treating biosolids, not necessarily right out of the wastewater treatment plant where they’re still very laden with water, but if you can dry these out, there’s some techniques that you could then use to destroy the PFAS,” Crimi said.  

Detecting the chemicals is a challenge as well, especially for the general homeowner or consumer who may want to know more about their drinking water, she said. 

“It’s expensive, hundreds of dollars for a single sample,” she said. "You have to do all this preparation work to get a sample pure enough to be analyzed without ruining the extremely expensive equipment.”  

Spruce Haven Dairy is the first New York farm to make and use biochar, a charcoal made from manure. The biochar is applied to fields as fertilizer and offers beneficial nutrients to the soil. (Emily Kenny/Spectrum News 1)

She and her colleagues are working on a more immediate sensor technology that would be like a pH level test strip for a pool. 

“A person can detect whether PFAS is there or not even at really low concentrations. They can then distinguish between some groups of PFAS compounds. The technology is getting better and better to the point where it may be able to get to a single compound resolution,” Crimi said.  

And the results are nearly instantaneous, she said. 

“That’s hugely valuable compared to taking a sample, sending it off, getting the lab results and having uncertainty still in those results. When you have to wait, it’s often too late to know if you should be doing something different,” Crimi said.  

Reducing the source of PFAS

To reduce PFAS in the environment, New York state has prioritized reducing the source of them in consumer products.  

“There’s a lot of different sources that need to be attacked at a higher level and getting that out of the source will get it out of byproducts, which is our main priority and the biggest bang for our buck when we’re dealing with these materials,” said Molly Trembley, a representative of the New York Department of Enviornmental Conservation during a December meeting on PFAS in Steuben County. 

Trees reflect in the Cohoctan River which runs through the area where sewage sludge has been spread. (Emily Kenny/Spectrum News 1)

New York has banned the use and sale of firefighting foam, carpet, textiles, apparel and food packaging that contain PFAS.  

And a bill proposed in the state Senate and Assembly that would phase out the sale of various products containing PFAS such as paint, cleaning products, cookware, outdoor apparel and anti-fogging wipes has not made it out of committee. However, in a November meeting, state lawmakers said they want to strengthen laws prohibiting manufacturing and use of PFAS in consumer products.

Waste management solutions for sewage sludge 

The use of biosolids on farms began as a way to recycle the end product from wastewater treatment plants — a practice recommended by state and federal entities for decades. The semi-solid material has beneficial compounds for soils and crops, said environmental toxicologist and professor emeritus at Cornell University Murray McBride. The challenge is there aren’t any good alternatives to get rid of the sludge.

“Land application, turns out, is the cheapest option which has been the driving force, and some farmers want to have this material because it saves them money on fertilizer,” McBride said. 

A kiln burning at Spruce Haven dairy farm. (Emily Kenny/Spectrum News 1)

There is some research into pyrolyzing — the process of using high temperatures to destroy certain materials — the sewage sludge to make biochar, McBride said. In Cayuga County, Spruce Haven Dairy Farm became the first New York farm to use biochar, a charcoal made from their cows’ manure, as fertilizer. 

“The dairy manure you could say is almost a surrogate for sewage sludge,” said Johannes Lehmann, the researcher who is leading the project at Spruce Haven Dairy. 

The view of the riverbed in Bath. (Emily Kenny/Spectrum news 1)

The dairy farm has about 2,000 milking cows and 1,700 heifers. 

“Pyrolysis and biochar is one approach to think about integrating into waste management at large because if we can make it work with dairy manure, we can probably make it work with a lot of [other] wastes as well,” Lehmann said.  

WATERTOWN, NEW YORK - JANUARY 23, 2025: Angel French, the chief operating officer at the Watertown wastewater treatment plant said they have only gotten positive feedback from farmers who use their biosolids. The plant takes in 10 million gallons of water per day and produces 4,000 wet tons of biosolids every year. (Photo by Emily Kenny)

The challenge with sewage sludge that doesn’t apply to dairy manure is the contaminants like heavy metals and PFAS chemicals, he said. 

“Any metals that are in the sludge that go through pyrolysis, they are still metals. They are not disappearing. That’s different of course for anything organic such as antibiotics, hormones, pathogens and potentially even PFAS and microplastics that can be denatured at high temperatures,” Lehmann said.  

The research is ongoing, and it would require more energy into making sewage sludge containing less PFAS.

An operator at the Watertown wastewater treatment plant scrapes biosolids from the press. (Emily Kenny/Spectrum News 1)

“The PFAS amounts in biochar is negligible compared to a sludge that goes [on land] but people have found PFAS then in the gas phase,” Lehmann said. 

The idea of making biochar from sewage sludge could work, but not without extensive research into the outcomes of this process, Lehmann said, including determining whether biochar made from sewage sludge is safe for use on land. However, pyrolysis would reduce the biosolids by 95% volume and could offer another solution, Lehmann said. 

Spruce Haven Dairy is the first New York farm to make and use biochar, a charcoal made from manure. The biochar is applied to fields as fertilizer and offers beneficial nutrients to the soil. (Emily Kenny/Spectrum News 1))

“Pyrolysis could be an intermediate step towards just reducing the problem because you can still landfill biochar, but you are landfilling 95% less,” he said.  

This would also offer the ability to investigate whether the biochar can be used in a way that is safe and beneficial.

“Is this material useful? Can we use it as a fertilizer? Can we make something innovative? That would be the question,” Lehmann said.