PFAS Contaminants: Where They Came From, Why They Persist & What We Can Do
The chemical group referred to as PFAS (per- and polyfluoroalkyl substances) — more popularly called “forever chemicals” — is rapidly evolving into one of humanity’s most severe environmental crises. Found in soil, water, air, plants, and animals everywhere across the globe and tainting the blood of virtually all Americans, PFAS are linked to a host of human diseases, including cancer.
The U.S. Environmental Protection Agency (EPA) believes two specific PFAS compounds, PFOA and PFOS, are toxic enough that the agency recently lowered its safe drinking water health advisories for the compounds to levels modern environmental laboratories cannot detect. The agency also published a similarly low health advisory for Gen-X, a newer PFAS compound created as a “safe” replacement for PFOA.
And like it or not, if you drank a glass of water today, you probably ingested some PFAS, too, even if your water was filtered.
So, where did this problem come from, and how did it get this bad? More importantly, what can be done about it?
What Are PFAS?
PFAS are a diverse group of manufactured chemicals numbering in the thousands, widely used in commercial manufacturing, beginning in the late 1940s. All PFAS molecules are comprised of carbon and fluorine atoms.
The carbon-fluorine bond structure imparts unique properties to the molecules, such as water and stain repellence, which can be modified in many ways for commercial uses. Although PFOA and PFAS have mostly been phased out, new chemistries have been developed to take their place. Coined by some as a game of chemical “whack-a-mole,” the result is that many PFAS remain in many manufacturing supply chains. Industries/applications that have used PFAS in their manufacturing processes include:
- Plastics production
- Petrochemical refining
- Metal finishing (e.g., chrome plating)
- Pulp and paper manufacturing
- Fire suppressing materials (foams) and firefighting gear
- Pulp and paper manufacturing
- Textiles and carpeting
- Renewable energy and communications (Li-ion batteries, electric vehicles, cellphones, tablets)
- And many others
In short, we contact or are surrounded by PFAS continuously, resulting in more than 98% of Americans with PFAS in their blood.
Where Did PFAS Come From? (A Brief Origin Story)
In 1938, a chemist working in a New Jersey Dupont lab “discovered” tetrafluoroethylene while attempting to make a new, “safer” chlorofluorocarbon-based refrigerant. Its non-stick, chemical- and thermal-resistant properties were quickly recognized during follow-up testing, and soon after, the mysterious, slippery substance known as Teflon was born.
Teflon was initially used to support U.S. World War II efforts. Teflon’s military uses included: gaskets and coating valves/seals in plutonium production and uranium enrichment, the nose cones of bombs to deflect radar, lining fuel tanks, and making explosives.
Following WW II, Teflon began to be incorporated into commercial products. A new plastics plant in Parkersburg, WV, was built to support this effort. Significant PFOA contamination discovered near the plant leading to the 2017 class action lawsuit settlement of $672 million was the subject of the 2018 documentary, The Devil We Know and the 2019 major motion picture Dark Waters.
A key ingredient to making Teflon commercially viable was a specific PFAS compound, called PFOA, manufactured by 3M. PFOA, also called C8 due to its eight carbon atoms, was increasingly ‘baked into’ many everyday household items and commercial manufacturing processes. Thousands of chemicals with the same carbon-fluorine backbone have since been created for commercial use.
In June 2022, the U.S. EPA updated its health advisory for PFOA in drinking water to 4 parts per quadrillion, a historically low designation compared to other groundwater contaminants and a concentration below detection limits for most laboratories. The concentration equals a single drop in 230 million gallons of water (about 350 Olympic swimming pools). Although PFOA and PFOS have largely been phased out, many other PFAS are currently found in U.S. supply chains today.
Why Are PFAS So Problematic?
Three factors merge to create a perfect storm, making PFAS uniquely problematic as environmental contaminants.
- Persistence: The carbon-fluorine bond comprising PFAS is one of the strongest in synthetic chemistry. This feature, handy for many industrial applications, makes them exceedingly resistant to breakdown. Unlike most organic chemicals, PFAS are not known to degrade over a typical human lifespan, earning their “forever chemicals” nickname.
- Prevalence: PFAS have been widely used across a spectrum of manufacturing processes for eight decades. Over time, they have become globally widespread across all environmental media.
- Health risks: Our understanding of PFAS and the risks they pose are rapidly evolving. However, mounting evidence suggests that exposure to even small amounts of certain PFAS compounds such as PFOA and PFOS increases the risk of disease. Reported health effects include thyroid disease, decreased fertility, lower birth weight, high cholesterol, decreased immunity, and cancer.
What Is Being Done Now to Address These Contaminants?
PFAS are a primary focus of the environmental industry. The EPA, state environmental agencies, and remediation professionals are taking steps to address PFAS contamination. The EPA has classified PFOA and PFOS as “hazardous substances” and aims to formalize maximum contaminant levels (MCLs) allowable in drinking water later this year. Many states, including New York, California, and most New England and Midwestern states have established their own version of MCLs ahead of the EPA.
Significant PFAS exposure risks occur when the chemicals enter groundwater, where they can impact drinking water sources and get into our food supply chains. The most common method to address PFAS removes the exposure risk by pumping groundwater above the ground and filtering the PFAS out of it using carbon, resins, or other filtration media. The approach, known as pump & treat, creates large amounts of PFAS-contaminated materials that must be disposed of in a landfill.
However, since PFAS do not degrade, they are highly likely to leach out of the landfills and re-contaminate groundwater, effectively recreating the problem elsewhere. Landfills are a significant source of PFAS pollution across the United States. Incineration of PFAS wastes is not favored and is increasingly not allowed. Due to the lack of studies showing PFAS contaminants can be incinerated safely, the U.S. Department of Defense recently instituted a moratorium on the practice.
Technologies destroying PFAS are primarily in the experimental stage and entail elaborative processes with high energy inputs needed to break the carbon-fluorine bonds. Most judge these destructive technologies as unsustainable for treating groundwater contaminated with PFAS, while research and testing to improve their efficiency continues.
One proven and highly sustainable technology involves the injection of a colloidal activated carbon (CAC) material that treats PFAS by immobilizing them in place. Commercially known as PlumeStop®, the CAC material is injected directly into the subsurface to treat groundwater, painting the sand particles or rock housing the groundwater with a coating of microscopic carbon particles. The treatment process creates an in-ground filtering system effectively removing PFAS from groundwater for decades. PlumeStop is currently being applied at PFAS-contaminated sites worldwide to prevent the risk of exposure to these hazardous chemicals. The longest-running PFAS treatment has been effective for more than six years, with an independent modeling expert suggesting it will remain effective for more than 60 years.
What Can You Do About It?
While the EPA, state/local agencies, and the environmental industry at-large work to eliminate PFAS exposure risk, there are a few simple steps anyone can take to reduce exposure to these harmful chemicals.
- Start with awareness. Become aware of PFAS, the potential risk of chemical exposure, and spread the news. Reading this article is a good place to start.
- Research your local water utility to learn if the water supply has been sampled for PFAS. If they are detected, ask what is being done about it. Most water utilities provide periodic reports on water quality and can be found through the tap water database tool published by the Environmental Working Group.
- Look for PFAS-free alternatives in your consumer purchases. Inquire about everyday consumer products that may contain PFAS, including food wrappers, cosmetics, dental floss, and weather-resistant clothing. Look for safer alternatives. Although you will likely not be at significant risk by continuing to wear your PFAS-treated shoes and boots, the continued manufacturing usage of PFAS leads to the contamination of groundwater and drinking water, and the risk of health effects.
About the Author
Maureen Dooley is Vice President, Industrial Sector for REGENESIS, where she is responsible for business development and technical support associated with industrial contaminant remediation on sites throughout North America. Recently, she has focused on site remediation for PFAS and chlorinated solvent impacts, working with manufacturing clients and property developers to mitigate risk and liabilities associated with these contaminants.
Earth911 August 2, 2022 at 04:39PM
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