Experts discuss how PFAS got into our water, and efforts to eliminate ‘forever chemicals’



A Dayton Daily News investigation found more than a dozen Miami Valley public water systems have levels of a toxic, man-made chemical that exceed standards proposed by the U.S. EPA, and area leaders and scientists say work is needed to meet that change and keep drinking water safe.

Per- and polyfluoroalkyl substances (PFAS) are a group of powerful, toxic chemicals created to be resistant to heat and other elements. PFAS are very difficult to break down due to their chemical composition, which consists of strong bonds of fluorine and carbon atoms.

This group of substances are called “forever chemicals” by some for that reason, according to University of Dayton Research Institute scientist Tak Yamada.

Read the whole project:

- PFAS detected in 15 local public water systems over proposed EPA guidelines

- Experts discuss how PFAS got into our water, and efforts to eliminate ‘forever chemicals’

- Dayton says they’re working to address PFAS, but won’t go into detail

- Concerned about PFAS contamination? Here’s 5 things you can do at home

- Health, infrastructure costs of PFAS in the billions; Who should pay for it?

Local researchers and officials are planning ways to address these forever chemicals in coming years, but some work is already underway.

Producers of PFAS more than 60 years ago did not have an understanding of the long-lasting health implications of the substance they created, Yamada said. They created the persistent group of chemicals to extinguish flames, particularly fire sparked by fuel.

Yamada said that in the Dayton area, a major PFAS contamination source was firefighting foam used at Wright-Patterson Air Force Base and other area firefighting training centers.

Other sources of PFAS

These chemicals, once expelled, permeate water sources through runoff and rainwater. PFAS take thousands of years to break down in the environment and can travel far, Yamada said.

The most common types of PFAS are perfluorooctane sulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), which have been found in recent years at levels higher than the U.S. EPA’s proposed 4 parts per trillion (ppt) limit in 15 public water systems throughout the region, according to Ohio EPA data.

One part per trillion is equivalent to a grain of sand in an Olympic-sized swimming pool.

PFAS is used in many products that people interact with on a daily basis: food packaging, baby products, cosmetics and non-stick pans, in addition to PFAS that has been detected in water systems. PFAS has also been detected in wildlife, specifically fish.

Environmental Working Group, a group of scientists who study drinking water and the impact of its contaminants on health, says PFAS in drinking water is a major concern of their group and no exposure to PFAS in drinking water is safe.

Incinerating PFAS

Yamada said the proposed limit of no more than 4 ppt for PFOA and PFOS for public water systems may be too difficult of a goal for local governments to achieve in a few years time.

“70 parts per trillion to four parts per trillion… that’s a big change,” he said.

PFOS and PFOA are also only two of the thousands of different PFAS chemicals that exist. They are the most common and are not as difficult to filter out compared to newer versions of PFAS.



He and his fellow researchers at the University of Dayton Research Institute are looking into solutions for ridding the environment of what was once thought to be a permanent issue. One approach involves literally incinerating PFAS.

“We burn the substances in a well-controlled environment, then collect and analyze the gas emissions to see if any PFAS remain and what kind of incineration byproducts are produced if they are not completely decomposed,” Yamada said.

The researchers are collaborating with the EPA and with the Department of Defense for this project, as well as a few businesses, as they continue their studies of PFAS.

‘A brutal circle’

Substances like activated carbon are used by many water treatment facilities to keep harmful contaminants out of the drinking water they send out to their communities.

But just like with filters used in water pitchers, after so much time and use, the activated carbon becomes “spent” and is no longer usable for effective filtration, Yamada said.

When that activated carbon — which is now contaminated with PFAS chemicals — becomes spent, it has to be discarded in some way.

Warren County water department deputy director Chris Wojnicz said this is a major concern of his water department.

Because PFAS does not naturally disappear in an environment, if this activated carbon is disposed of in environments where it’s exposed to rain or can leach through soil, it can appear back in water systems.

“It’s a brutal circle,” Wojnicz said. “And until we figure out how to break the circle, this stays here.”

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