By now, you may have heard of PFAS (per- and polyfluoroalkyl substances), a class of artificial chemicals found in soil, water, air, plants, animals, and in the bodies of virtually all Americans. Popularly known as the 'Forever Chemicals,' exposure to PFAS has been linked to numerous adverse health effects, including hypertension, low birth weights, immunodeficiency, thyroid disease, and cancer.
News releases detailing PFAS impacts are occurring daily, including a recent report of PFAS discovered in the City of Prescott's water supply. As coverage increases, public concern over PFAS has also risen. Below are five of the most common PFAS questions, with answers from an insider who, alongside colleagues, is actively working to solve PFAS contamination problems globally.
Sidebar - PFAS in Arizona's Drinking Water
A 2018 report published by the Arizona Department of Environmental Quality (ADEQ) identified 68 public water systems near suspected sources of PFAS. Out of the 109 wells sampled from these systems, six (5.5%) contained PFOA/PFOS above the previous U.S. EPA Health Advisory levels of 70 parts per trillion. However, since this report was published, the U.S. EPA has lowered its Health Advisory levels to 0.004 parts per trillion for PFOA and 0.02 parts per trillion for PFOS. These levels are well below the laboratory detection limits used for the sampling.
Q #1 - What are PFAS?
PFAS are a diverse group of manufactured chemicals numbering in the thousands and widely used in commercial manufacturing since the late 1940s. PFAS have several unique properties, including stain & water repellence and heat resistance, which make them popular for many commercial uses. Consequently, over the years many industries have used PFAS in their manufacturing processes, including:
Firefighting (fire-suppressing foams, firefighting gear and equipment)
Plastics production
Petrochemical refining
Metal finishing (e.g., chrome plating)
Pulp and paper manufacturing
Textiles and carpeting
Pesticides
Semi-conductors
Pharmaceuticals
Cosmetics
Renewable energy and communications (Li-ion batteries, electric vehicles, cellphones, tablets)
And many others
As a result of their widespread usage, we are in constant contact with PFAS.
Q #2 - Where did PFAS come from?
Like many technological innovations, polytetrafluoroethylene, was accidentally 'discovered' in 1938 by a chemist working in a New Jersey Dupont® laboratory. The discovery revealed a substance with remarkable non-stick properties, leading to the birth of Teflon®, the first known PFAS.
Early on, Teflon was used almost exclusively for U.S. WWII efforts but became incorporated into commercial products rapidly soon after. In the following decades, many new PFAS were created for thousands of industrial applications and consumer products. Although the more notable PFOA and PFOS have been banned from manufacturing in the U.S., many PFAS remain in our supply chains today.
Q #3 - How Bad is the PFAS Problem?
In a word: BAD.
One can only guess the full scope of PFAS impacts on the environment and human health due to the global scale of the problem and the unknown health effects caused by most PFAS.
In June, two of the most widespread and studied PFAS compounds, PFOA and PFOS (perfluorooctane sulfonic acid), were reported to be more harmful than initially thought. Recent toxicology studies caused the U.S. EPA to lower its safe drinking water Health Advisories (HA) levels thousands of times lower than the previous (2016) HAs. The new ‘safe’ levels are equal to a drop or two in a soccer stadium full of water and cannot be detected by modern laboratories. According to a recent Stockholm University study, when compared to the new HA levels, rainwater falling anywhere on Earth- even as far off as Antarctica! -is considered unsafe to drink. Complicating matters further, most PFAS go unnoticed since laboratories only look for a few dozen out of the potential thousands of PFAS in the environment.
Although PFAS exist in trace amounts almost everywhere, they cause the biggest problems in groundwater. Like a slow-moving stream, groundwater moves from high to low elevation beneath the surface. PFAS are very mobile and can effortlessly move with the groundwater for miles to impact downstream drinking water wells or surface waters. According to one estimate, 200 million people may be drinking PFAS-contaminated water in the U.S. But the highest concentrations and most significant health risks occur downstream of PFAS source zones or 'hot spots' where the chemicals were initially released. The known PFAS sites causing the highest risks of exposure must be addressed quickly to avoid further unnecessary, costly, and health-threatening damages.
Q #4 - How are PFAS Being Cleaned Up in Groundwater Now?
The most familiar method for PFAS cleanup in groundwater is extraction and treatment (i.e., pump & treat). This method pumps the groundwater aboveground and filters the PFAS out of it using carbon, resins, or reverse-osmosis filtering. Pump & treat is the process used to make water safe for drinking after PFAS enter drinking water wells. But pump & treat is not the way to clean up PFAS contaminants in groundwater before they impact drinking water.
Besides being inefficient, costly, and generally unsustainable, pump & treat systems create large amounts of PFAS-contaminated waste that must be disposed of in a landfill. Since PFAS do not degrade, they will eventually leach out from the landfills and re-contaminate groundwater elsewhere, effectively spreading the problem. Landfills are significant sources of PFAS pollution across the country. In addition, pump and treat systems require a significant amount of energy to run.
As a result, there is an intensive search for technologies that can destroy PFAS. But the technologies available now and in the foreseeable future require massive energy to break the carbon-fluorine bonds, resulting in extraordinary costs to operate. Most industry experts agree that these destructive technologies are unsustainable for treating PFAS in groundwater.
A Proven PFAS Solution
While most methods for addressing groundwater contamination do not work for PFAS, one solution has proven effective at eliminating PFAS exposure risk. Since 2016, a low-cost and sustainable PFAS treatment approach has used colloidal activated carbon (CAC), a patented material called PlumeStop®, to contain the contaminants in place. The CAC material is fed directly into the groundwater, where it coats the aquifer solids with microscopic carbon particles.
The treatment process creates an in-ground filtering system, forming a barrier that removes PFAS from groundwater before it contaminates a drinking water well or a stream. Since the treatment occurs below ground, there is no pumping involved. Installed CAC treatments do not generate toxic PFAS wastes and do not consume energy or create emissions. PlumeStop treatments prevent PFAS movement for decades upon a single application. The warranty-backed approach using CAC is being applied at PFAS-contaminated sites worldwide to prevent the risk of exposure to these hazardous chemicals and protecting communities where exposure to PFAS is now avoided.
Q #5 - What Can I Do About PFAS?
PFAS is a primary concern for environmental agencies and the environmental cleanup industry in the U.S. and worldwide. While environmental professionals work to find PFAS sources and clean up the contaminants, there are a few easy steps anyone can take to reduce exposure to these harmful chemicals.
Become educated about PFAS and the potential risk of chemical exposure and spread the news. Share PFAS-related information with your friends, family, and neighbors.
Research your local water utility to learn if the water supply has been sampled for PFAS. If PFAS contaminants have been detected, ask what is being done about it. Most water utilities provide periodic reports on water quality. These reports are also found through the Environmental Working Group's Tap Water Database search tool. Contact your local officials if you do not get the answers you need.
Buyer beware - Review ingredient lists and use your buying power to purchase PFAS-free alternatives to everyday products. These products are diverse, from food wrappers to cosmetics, dental floss to weather-resistant clothing. If you see chemicals with the letters “fl” together, look for safer alternatives. There is little to no risk in wearing the PFAS-treated shoes and boots you already own. However, the continued manufacturing processes using PFAS chemicals lead to groundwater and drinking water contamination and the risk of health effects for many.
Finally, rest in knowing that solutions to the highest risk PFAS problems are available and being implemented now.
About the Author:
Daniel Nunez has over 18 years of experience in environmental compliance, site investigation and site remediation. He provides technical and management expertise for soil and groundwater remediation projects, regulatory compliance, and client negotiations. Mr. Nunez has designed, implemented and managed various phases of site characterizations, feasibility studies, and full-scale soil and groundwater remediation at numerous contaminated sites in the Southwest United States and throughout Australia. His remedial expertise is related to PFAS, LNAPL, DNAPL, 1,4-dioxane, NDMA, perchlorate and nitrate both ex-situ and in-situ. He is currently the West Region Manager for REGENESIS. Daniel holds a B.S. in Chemistry from the University of California Irvine and an M.S. in Environmental Science from California State University Fullerton.
Comentarios