If you've heard the term "forever chemicals" and wondered what it actually means, you're not alone. PFAS have been showing up in headlines, regulatory filings, and procurement questionnaires with increasing frequency, but the foundational question—what they actually are and why they behave the way they do—often gets glossed over in favor of compliance checklists and management frameworks.
That's what this post is here to fix. Written by the PFAS experts at Reworld®, our Ultimate Guide to PFAS covers the business and operational side of PFAS management in depth. This post focuses on the fundamentals: what PFAS are, where they come from, how they get into the environment and the human body, and what makes them fundamentally different from other chemical hazards.
PFAS stands for per- and polyfluoroalkyl substances. It's an umbrella term covering a large and structurally diverse family of synthetic chemicals, not a single compound.
There are more than 12,000 individual PFAS, but they all share one defining characteristic: an exceptionally strong bond between carbon and fluorine atoms that makes them highly resistant to breaking down.
That resistance is what makes PFAS useful. And it's what makes them a problem.
PFAS were engineered to be durable. They resist heat, repel water and oil, reduce friction, and hold up under conditions that would degrade most other materials. Those properties made them a go-to solution across dozens of industries for decades.
But that same durability doesn't turn off at the end of a product's life. When PFAS enter the environment, they don't break down the way most substances do. They keep moving through soil, water, and living organisms without losing their structure.
The result is a set of characteristics that create real management challenges:
PFAS chemistry was first discovered in the late 1930s, and by the 1940s and 50s, industrial leaders were mass-manufacturing PTFE, PFOA, and PFOS. By the 1960s and 70s, PFAS had been incorporated into countless industrial and consumer applications. For roughly half a century, they were considered a success story in materials science.
The two most well-studied PFAS compounds, PFOA (perfluorooctanoic acid) and PFOS (perfluorooctane sulfonic acid), were the workhorses of that era. PFOA was used extensively in the production of Teflon and other fluoropolymers. PFOS became the active ingredient in Scotchgard and, starting in the 1960s, in the aqueous film-forming foam (AFFF) developed for military and airport firefighting operations.
Both have since been phased out or heavily restricted in the U.S. and globally. Their manufacturers voluntarily halted production of PFOS and PFOA in 2000. But phasing out two compounds didn't phase out PFAS. Manufacturers replaced them with newer, shorter-chain PFAS that were assumed to be less problematic. That assumption has proven to be overly optimistic.
PFAS don't appear in the environment from a single source. They get there through multiple pathways, often simultaneously.
PFAS contamination is not a localized problem. Because PFAS are mobile in water and stable in the environment, contamination from a single source can spread across large geographic areas over time.
The breadth of PFAS applications is part of what makes them so difficult to track and manage. They weren't used in one industry or one product category. They were woven into manufacturing processes, consumer goods, and industrial systems across virtually every sector of the economy.
|
Industry |
Application |
Why PFAS Were Used |
|
Food packaging |
Grease-resistant paper, wrappers, microwave bags |
Prevents oil and moisture from soaking through |
|
Textiles and apparel |
Waterproof and stain-resistant fabrics |
Repels water and stains without altering texture |
|
Cookware |
Non-stick coatings (Teflon) |
Reduces friction, prevents food from adhering |
|
Firefighting |
Aqueous film-forming foam (AFFF) |
Suppresses fuel fires faster than water alone |
|
Electronics |
Circuit board coatings, semiconductor manufacturing |
Protects components from moisture and chemical exposure |
|
Aerospace and automotive |
Hydraulic fluids, lubricants, seals |
Maintains performance at extreme temperatures |
|
Medical devices |
Tubing, coatings, implantable components |
Biocompatibility and chemical resistance |
|
Construction |
Sealants, caulks, roofing materials |
Weather resistance and durability |
|
Agriculture |
Pesticide formulations |
Improves spreadability and adhesion |
The practical reality is that PFAS became a default solution for any application that needed a surface or material to resist something: heat, water, oil, friction, or chemical attack. As Doug Rock, Senior Director of Pricing and Product Management at Reworld, put it, "If it sticks, shines, or glosses, it probably has PFAS in it."
The term "forever chemicals" isn't hyperbole. It's a reasonably accurate description of how PFAS behave in the environment and in biological systems.
The core issue is that PFAS have no natural degradation pathway. Most organic pollutants, even persistent ones, eventually break down through some combination of microbial activity, UV exposure, hydrolysis, or oxidation. PFAS resist all of these. The carbon-fluorine bond is simply too strong for the biological and chemical processes that break down other compounds.
When scientists say PFAS are persistent, they mean something specific. It's not just that PFAS last a long time. It's that they continue to move through natural systems, like water, soil, air, and living organisms, without losing their chemical structure.
A PFAS molecule released into a river in 1975 is chemically identical to that same molecule today. It may have traveled through groundwater systems, been taken up by fish, deposited in sediment, re-mobilized by flooding, and cycled through municipal water treatment. But it hasn't broken down.
PFAS contamination doesn't stay where it starts. Different PFAS compounds move through the environment in different ways, but the general pattern is the same.
This combination of persistence and mobility is what makes PFAS contamination so difficult to address. You can't simply wait for PFAS to degrade. You have to actively remove or destroy them, and even then, a contaminated site may continue receiving PFAS from other sources upstream.
The honest answer is: It depends on which PFAS, how much, and for how long.
The term “PFAS” represents a class of thousands of compounds. Not all PFAS compounds have been studied, and the ones we know the most about are the ones that have been around the longest, primarily PFOA and PFOS. For newer PFAS compounds, research is still catching up.
What we do know is enough to take seriously.
For PFOA and PFOS specifically, a substantial body of research has linked exposure to a range of health effects. The Agency for Toxic Substances and Disease Registry (ATSDR) and the EPA have reviewed this literature extensively. The health concerns most consistently associated with PFOA and PFOS exposure include:
The EPA's 2024 drinking water standards set maximum contaminant levels for PFOA and PFOS at 4 parts per trillion (ppt). The fact that the EPA set enforceable limits at that level reflects how seriously the agency views the risk, even at extremely low concentrations—and is just one example of how rapidly PFAS regulations are evolving across the U.S.
There isn't a single threshold that applies to all PFAS compounds or all people. The health risk depends on which specific PFAS compounds are present, the duration and route of exposure, and individual factors like age, body weight, and health status.
What the research does suggest is that there is no established "safe" level of exposure for the most concerning PFAS compounds. The EPA's 4 ppt standard for PFOA and PFOS was set specifically because health effects have been observed at concentrations approaching that level in long-term epidemiological studies.
For organizations managing PFAS-containing materials, the practical implication is this: the regulatory trend is toward lower limits and broader compound coverage, not higher thresholds and narrower scope.
PFAS enter the human body primarily through contaminated drinking water and food. Once inside, they don't behave like most chemicals. Rather than being metabolized and excreted quickly, certain PFAS bind to proteins in the blood and accumulate in organs, particularly the liver and kidneys.
According to CDC and ATSDR, most people in the U.S. have been exposed to PFAS and have it in their blood. That doesn't mean everyone is at immediate health risk. But it does reflect how deeply embedded PFAS have become across the food supply, water systems, and everyday products that people have been using for decades.
PFAS contamination refers to the presence of PFAS compounds in environmental media, drinking water, groundwater, soil, sediment, and air, at concentrations that may pose a risk to human health or the environment.
The challenge with PFAS contamination is that it doesn't look like anything. You can't see it, smell it, or taste it. It requires laboratory testing to detect, and the testing methods themselves have only recently become sensitive enough to measure PFAS at the parts-per-trillion levels now considered relevant for health.
PFAS contamination isn't just a problem for facilities with direct PFAS use. It can arrive through sourced materials, affect facilities near historically contaminated sites, and show up in wastewater streams that weren't previously monitored for PFAS. The starting point is always visibility: knowing where PFAS may exist before assuming they don't.
PFAS are a class of more than 12,000 synthetic compounds built around carbon-fluorine bonds. They were developed starting in the 1940s for their resistance to heat, water, oil, and chemical degradation. That same resistance makes them persistent in the environment and difficult to destroy once released. The term "PFAS" covers both perfluorinated compounds (where all hydrogen atoms on the carbon chain have been replaced by fluorine) and polyfluorinated compounds (where only some have been replaced).
Yes, PFAS are described as forever chemicals because they have no known natural degradation pathway. Unlike most organic compounds, PFAS do not break down through microbial activity, UV exposure, or hydrolysis. They persist in soil, water, and biological systems for years to decades.
Research on the most-studied PFAS compounds (primarily PFOA and PFOS) has linked exposure to increased cholesterol, liver effects, immune system changes, certain cancers, and reproductive health effects. For newer PFAS compounds, research is still ongoing, but the regulatory direction is toward treating the entire class with caution.
PFAS are found in drinking water and groundwater, soil, food, food packaging, stain-resistant textiles, non-stick cookware, firefighting foam, electronics, and many other products. The CDC and ATSDR have detected PFAS in the blood of nearly all Americans tested in national surveys, reflecting the widespread nature of exposure.
No. PFAS is an umbrella term for more than 12,000 individual compounds, and they don't all behave the same way. The most studied are long-chain PFAS like PFOA and PFOS, which have been linked to the most significant health and environmental concerns and are now heavily restricted or phased out in the U.S. When those were pulled from the market, manufacturers replaced them with shorter-chain alternatives like GenX chemicals and PFBS, which were marketed as safer. Research has since raised similar concerns about those replacements.
Yes, but it requires specific conditions and purpose-built PFAS destruction technologies. Breaking down PFAS requires sustained high temperatures above 1,100°C in a controlled combustion environment—conditions that most standard waste facilities aren't engineered to achieve.
Reworld Thermomechanical Treatment Facilities (TTFs) naturally meet those conditions. They operate under sustained high-temperature, controlled combustion parameters engineered to break powerful bonds, including the carbon-fluorine bonds that make PFAS so persistent. This isn't a general-purpose waste facility handling PFAS on the side. The engineering, operating conditions, and monitoring protocols are ideal for the specific requirements of PFAS destruction.
Reworld ReAssure™ PFAS Destruction program delivers this capability as an end-to-end managed solution:
If you're working through what PFAS exposure looks like in your operations and what your options are, our team can help you assess where you stand and what a realistic path forward looks like.
Connect with us to start the conversation.