As public concern about “forever chemicals” contamination escalates, scientists are working to better identify and track thousands of compounds that could unlock greater regulatory power and bolster plaintiffs’ ability to reap damages from polluters.

The goal is to determine a scientific “fingerprint"—a tool used in sampling and tracking other chemical pollution—for contamination sources of per- and polyfluoroalkyl substances (PFAS).

“Everybody is going to get into fingerprinting,” scientist and Oregon State University professor Jennifer Field told Bloomberg Environment. “Fingerprinting is the first step in finger-pointing.”

Hundreds of lawsuits, dozens of state regulators, and countless citizens concerned about chemicals in their blood are all grappling with the same question: Who will pay?

Often that question can’t be answered. Out of an estimated 6,000 PFAS chemicals, just over a dozen can now be reliably tested for, Field said.

She and other scientists are building the tools to better track the substances. But unlike gumshoes hunting bank robbers with unique fingerprints, scientists studying PFAS contend with myriad factors making the analysis much more murky.

Searching for Signatures

Researchers at the Columbus, Ohio-based Battelle Memorial Institute are developing a process to find signatures common to various sources of PFAS contamination.

The process works by creating a library of the chemicals, which is then grouped into categories, such as contamination that would indicate a source from a textile plant versus a paper plant.

“When we’re looking at a particular signature, it is so common across all of these sources,” Kavitha Dasu, principal research scientist at Battelle said. “We understand all of these things and we have come up with some of the distinct signatures of each of these applications, which chemicals are used for any particular application.”

Field said she and other researches across the U.S. are wrapping up research that will provide a tool to identify between 300 and 400 substances, and possibly up to 1,500.

Right now many substances can’t be identified with sufficient detail to differentiate between sources, she said.

“I think it’s the next big thing,” Field said. “We’re on the cusp now.”

Fractionation

But many researchers are more cautious about the state of the science, and say getting to the point where a contamination source could produce a unique fingerprint could still be far off.

And even if regulators learn how to narrow down potential chemical sources, determining who is responsible for those chemicals—and thus cleanup and damages—could still be a struggle.

At a National Ground Water Association conference on PFAS last month, several presenters highlighted difficulties of determining the source of PFAS contamination.

“Fingerprint, to me that’s like a detective show, where they lift it, and it’s the thing that seals the case, they catch the killer,” Scott Bell, senior environmental engineer and vice president for LimnoTech said. “It’s not like that.”

In a presentation, Bell showed how samples of contamination from different sources can have some overlapping attributes, making source attribution challenging.

Another complicating factor is the pervasiveness of the chemicals, found in water and people’s blood across the country.

And because some PFAS chemicals have gone through various iterations over the years and companies have used different formulas, water samples can have a blend of different formulations.

Pulling one sample doesn’t tell the whole story, Adam Janzen, an environmental engineer with Barr Engineering Co., said. As they move through groundwater the chemicals go through a process called fractionation, which means parts of a mix of multiple compounds in water will “stick” to soil closer to the contamination source.

A sample pulled close to a source could therefore have a different composition than one taken further away.

Finger Pointing

Should scientists overcome these practical difficulties, fingerprinting and related analytical tools could greatly clear up liability determinations in hundreds of lawsuits, especially cases with multiple sources of PFAS contamination.

Michigan has become a bellwether for the limitations of the current science. The state has the most known PFAS contamination sites, and a statewide survey found PFAS in 10 percent of public drinking water sources.

After state regulators found PFAS near an elementary school in Robinson Township, Mich., the state began groundwater tests to trace the chemicals back to potential sources. So far, the studies haven’t found a source.

A separate proposed class action in the U.S. District Court for the Western District of Michigan claims that 3M, Georgia-Pacific LLC, and a Georgia-Pacific subsidiary must pay up for PFAS contamination found in the Parchment, Mich., water supply at levels up to 26 times the U.S. EPA’s nonbinding health advisory of 70 parts per trillion.

The residents allege that substances leached into the water supply from a landfill associated with a now-defunct paper mill near the city, leading to a switch in municipal water and concerns over long-term health impacts for the area’s 3,000 residents.

Although Georgia-Pacific, which is owned by Koch Industries, has been assisting the Michigan Department of Environment, Great Lakes, and Energy (EGLE) with a groundwater investigation, the company contends it isn’t legally responsible for the contamination.

Instead, the paper company is pointing the finger at nine other sources of potential liability, including nearby manufacturing companies, an auto wash facility, former owners of the landfill, and EGLE itself, which was formerly called the Michigan Department of Environmental Quality.

‘More Information’

Aaron M. Phelps, a partner in Varnum LLP’s Grand Rapids office, said regulators countrywide are in the early stages of PFAS investigation, “so I think that anything that helps us get more information faster is better.”

Some cases are clear-cut, Phelps said. Fingerprinting won’t be necessary, he said, in the 200 cases in which he represents 400 Michiganders suing shoemaker Wolverine World Wide and chemical producer 3M.

While the companies deny liability, the residents claim substances from a Wolverine tannery in Rockford, Mich., seeped into nearby drinking water, causing health concerns. The tannery is on Wolverine’s property, and they purchased their PFAS chemicals from 3M, the residents claim.

In murkier situations, like at a landfill where multiple companies may have disposed of chemical waste, better analysis from fingerprinting could come in handy.

“If somebody dumped 100 tons and another person only dumped 1 ton, that would probably be relevant to the courts in terms of determining a percentage of fault in that contamination,” Phelps said.