A group of thousands of chemicals known as perfluoroalkyl and polyfluoroalkyl substances (PFAS) have made it difficult for researchers to understand their complexities.

“I have been telling my students that this is the issue they get to deal with for the next 15 to 20 years,” said Doug Daley, a professor of environmental resources engineering at SUNY College of Enviornmental Science and Forestry in Syracuse.  

PFAS chemicals are not naturally occurring despite some of the naturally occurring components like fluorine and carbon. They were manufactured for specific purposes, Daley said. Some of the common purposes are non-stick cookware, fire retardant clothing, and waterproof clothing. 

NOVEMBER 18, 2024 - BONNY HILL, NY: Leslie 'Skip' Smith's pond and drinking water well whcih are both contaminated with PFAS chemicals. Smith stocked the pond with fish but now only does catch and release. He won't allow anyone to eat the fish. (Photo by Emily Kenny)

“If I go look for PFAS anywhere, I will find them in one form or another,” Daley said. 

These chemicals have been used in products for decades, but there has recently been increased concern that Daley attributes to having the technology to determine how prevalent they are.

“I think they’ve emerged more recently because they’re omnipresent. They are in our bloodstream; they are in our body organs because we’re exposed to them through any number of avenues,” Daley 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)

Another emerging concern comes from the use of sewage sludge, or biosolids, being spread on farms as fertilizer.

“Biosolids are a semi-solid material that results from treating wastewaters, domestic wastewaters that all residents, commercial establishments and manufacturers generate,” Daley said.  

In the 1970s, farmers began using these biosolids on their farmland as fertilizer. 

“Biosolids came into popular use because we recognized the value contained in that organic material for nutrient management, nitrogen, phosphorus and some of the micronutrients that are essential for keeping our soils healthy, and then of course, the carbon that’s in there also enhances soil health and productivity of soils,” Daley said.  

CAMERON MILLS, NEW YORK - NOVEMBER 18, 2024: Antlers which Tim Hargrave has found and some from deer he has hunted. Hargrave has lived on the property for 59 years. He hunts the nearby deer and harvests them for meat. "It's too late for me now," he said, referencing the PFAS chemicals which he blieves contaminate the deer. (Photo by Emily Kenny)

Some of the biosolids are put into a landfill, others are spread on fields, but something has to be done with these materials, Daley said.

“Individually, we flush our toilet, and we don’t think about what happens to it, but the folks at the end of the pipe manage our wastewaters in a way so that we don’t have adverse impacts on the local environment. Consequently, the wastewater treatment facilities have to deal with this material,” Daley said.  

SUNY ESF was given funding from the New York Department of Environmental Conservation to research PFAS compounds going in and out of wastewater treatment plants, Daley said. His research models a study done in Michigan.

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)

“What they found in Michigan was that the facilities that had industrial wastewater contributors within their service area were the most likely to have elevated PFAS concentrations in their biosolids,” Daley said.  

And facilities that were taking wastewater from residential contributors had lower concentrations of PFAS compounds than facilities with industrial wastewater contributors. Daley said the Michigan study looked at about 25 compounds, but his research focuses on 40 that may skew their totals higher. 

The results of his research can’t be divulged yet, but he said they have been consistent with what other states have seen.  

“If you’ve got industry in your service area, you’re probably going to see elevated PFAS compounds but just as a reminder, we’re all contributing PFAS compounds to our domestic wastewater on a regular basis,” Daley said. 

Jean Bonhotal, director of Cornell University’s Waste Management Institute, said there should be a temporary ban on the spreading of biosolids until researchers learn more about PFAS.  

“Until more of the scientific data is gathered and we can access whether the lands are contaminated,” Bonhotal said. “It’s one of those things that’s sleepy but it’s been growing.”

Bonhotal said there is no safe level of exposure to these chemicals, and we don’t know much about the health impacts of PFAS.  

“There is no safe level of exposure to PFOS and PFOA and there’s 15,000 of these chemicals out there. The research is being done, and the research is going to take a long time. It’s coming fast and furiously, but it’s going to take a long time,” Bonhotal said.