PFAS stands for “per- and polyfluoroalkyl substances.” These substances have really caused a big dustup recently because the EPA has now established safe drinking water limits for select PFAS. This obstinate group of compounds has been christened “forever chemicals” and here are some interesting highlights and facts about PFAS.
What are PFAS
PFAS consist of man-made chemicals that had been widely used in various industrial and consumer products since the 1940s. Their usefulness lies in their ability to repel water, oil, and stains. PFAS are most commonly found in products like non-stick cookware, waterproof clothing, food packaging, and firefighting foams. PFAS are concerning because of their persistence in the environment and their potential health effects.
Why they are called “forever chemicals”
These chemicals are highly resistant to degradation, earning them the nickname "forever chemicals." They can accumulate in the environment, including water and soil, and may also accumulate in the human body through food and water consumption. The primary reasons why they are so persistent include:
Chemical Structure
PFAS utilize carbon-fluorine bonds, some of the strongest chemical bonds known making them highly resistant to degradation through chemical, biological, or environmental processes.
Environmental Persistence
Once PFAS enter the environment, they do not easily break down over time. They can persist for decades or even longer. Some other chemicals we remediate can be oxidized, volatilized, or bioremediated with relative ease compared to PFAS. What makes them so useful in non-stick cookware also makes them extremely difficult to remediate.
Bioaccumulation
PFAS can accumulate in the environment and within living organisms, including humans. Once they enter the food chain or water supply, and if we consume them, they will build up in our bodies over time.
Health Concerns
Exposure to PFAS has been linked to various health problems, including weakened immune function, developmental issues, hormone disruption, and certain cancers.
Industries most often associated with PFAS
Some of the key industries and manufacturing activities that have historically been linked to PFAS contamination include:
Textiles and Apparel Manufacturing
More specifically, those that produce waterproof and stain-resistant textiles such as outdoor clothing, carpets, cloth umbrellas and shades, and upholstery.
Non-Stick Cookware Production
PFAS were a common component of non-stick coatings, such as Teflon.
Food Packaging
Grease-resistant wrappers and containers for fast food and takeout have utilized PFAS. When they come into contact with food, PFAS can leach out and potentially contaminate food products.
Firefighting Foams
Foams used for firefighting and fire training exercises were manufactured with PFAS. These foams were used widely at airports, military bases, and industrial sites. Accidental releases during manufacturing, spills associated with training activities, and large fires were contributors to PFAS contamination.
Chemical Manufacturing
As with most chemicals, the leading cause of contamination is from releases occurring during manufacturing or from their disposal. One of the more common manufacturing processes using PFAS is metal plating operations that use PFAS to enhance surface properties.
Paper and Packaging Production
Microwave popcorn bags and fast food wrappers have historically been treated with PFAS to impart grease and moisture resistance.
What is being done now to control PFAS
Efforts are underway globally to reduce PFAS use, regulate their disposal, and remediate contaminated sites to mitigate the environmental and health impacts associated with these chemicals. The EPA’s recent PFAS drinking water limits will reduce the public’s consumption of these chemicals from our public water sources and bottled water. An interesting side note is that PFAS in bottled water is most commonly associated with the source of the water and not the plastic bottle (however, polyethylene terephthalate (PET) plastic commonly used in water bottles may release antimony, phthalates, styrene, and microplastics; a condition worthy of discussion in another blog). Some PFAS are still legal to use in manufacturing but are being phased out with the cost of cleanup and exposure liabilities being a driving force in the reduction of their use.
How should I address PFAS in my Phase I ESA
The industries that are most often associated with PFAS discussed above may be used as a general screening tool into the possibility of a recognized environmental condition being associated with the subject property. Since ingestion is the main issue associated with PFAS and they are not volatile, impacts from adjacent sites are not expected to be significant. Exceptions exist such as a site using a well water for potable water next to a contaminated site or a site dewatering for construction next to a contaminated site. When interviewing the Key Site Manager, it would be advisable to ask if they were aware of the use of any PFAS. The determination of whether a recognized environmental condition exists on a subject property due to onsite PFAS does not differ greatly from other chemicals. Factors such as how long PFAS had been used, how it was stored, where was it stored, in what quantities, how was it applied, and whether there were any reported spills or releases are all factors that will contribute to your findings and opinions.
How should I address PFAS in my Phase II ESA proposal
From what I have been able to glean, PFAS do not appear to be as pervasive as a chlorinated solvent. I would therefore presume that that they are not likely to impact the subsurface via concrete pipes or controlled spills on concrete slabs or other intact surfaces. If there had been a release to the subsurface, the PFAS would likely be detected in the soil regardless of how long ago a release had occurred. Shallow soil sampling in suspect areas would therefore be my choice as a screening tool.
Currently, there are several analytical methods for testing for PFAS. Methods 537N and 1633 are the most commonly used, but other methods are in the process of being proposed. These methods, much like TO-15, provide you with a long list of compounds that are detected in each sample. My laboratory charges between $350 (for 537N) and $500 (for 1633). At this time, the EPA is looking at 1633 as the standard, but because its costs are prohibitive, I would guess that changes will come in the future. Based on their characteristics, I am not aware of any preservative needed in taking or shipping the samples to the lab but for now, refrigeration appears to be the industry standard.
Summary
PFAS are one more item we will now need to add to our Phase I ESAs. Good luck and please feel free to comment or call us anytime.
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