Per- and Polyfluoroalkyl Substances (PFAS) are a vast group of synthetic chemicals used since the 1940s in countless industrial and consumer applications. Their chemical structure, anchored by an extremely strong carbon-fluorine bond, makes them uniquely resistant to heat, water, oil, and degradation. This stability is why they are often labeled “forever chemicals,” persisting in the environment and in living organisms for exceptionally long periods. Due to their ubiquitous nature, most people have some level of PFAS detectable in their blood. Managing the body’s burden of these persistent chemicals is a growing focus of environmental health research.
Understanding How PFAS Persist in the Body
The persistence of PFAS in the human body stems directly from their unique chemical composition. Unlike many toxins the body can metabolize and break down, the carbon-fluorine bond in PFAS is virtually unbreakable by human enzymes. The body, therefore, has no effective metabolic pathway to chemically degrade these compounds.
PFAS are primarily filtered through the kidneys and liver for elimination via urine and bile. However, many PFAS compounds are highly efficient at binding to proteins in the bloodstream, particularly Human Serum Albumin (HSA). This strong protein binding keeps the chemicals circulating in the blood and prevents them from being freely filtered out by the kidneys.
The small amount of PFAS excreted into the bile can be reabsorbed back into the bloodstream through a mechanism called enterohepatic circulation. This constant cycle of excretion and reabsorption significantly slows the overall elimination rate. This results in a prolonged biological half-life. For two of the most studied compounds, PFOA and PFOS, the half-lives are estimated to be approximately 2.3 to 3.5 years and 3.4 to 5.5 years, respectively.
Clinical Approaches to Accelerating PFAS Excretion
Given the long half-lives of PFAS, researchers have explored clinical interventions to accelerate their removal from the body. Standard medical detoxification methods like hemodialysis are generally ineffective because the strong binding of PFAS to serum proteins prevents them from passing through the dialysis membrane. Current research focuses on interrupting the enterohepatic circulation or physically removing the compounds from the bloodstream.
Bile Acid Sequestrants
One promising research area involves bile acid sequestrants, medications normally prescribed to lower cholesterol. Compounds like cholestyramine and colesevelam work by binding to bile acids in the intestine, preventing their reabsorption and promoting excretion in the feces. Since PFAS are excreted in the bile, these drugs can effectively trap the PFAS compounds and accelerate their removal via the fecal route.
Recent studies show that bile acid sequestrants can significantly reduce serum concentrations of some PFAS compounds. One medication demonstrated reductions as high as 40% for certain PFAS variants over a treatment period. While encouraging, this approach is not yet a standard treatment. Researchers are still investigating whether faster clearance translates into measurable health benefits and if long-term drug use carries acceptable risks.
Blood and Plasma Donation
A more immediate, voluntary intervention showing measurable success is regular blood or plasma donation (phlebotomy). This method physically removes the PFAS compounds that are bound to the proteins in the blood serum. A randomized clinical trial involving firefighters, a group often exposed to high levels of PFAS, provided specific data on this approach.
The trial found that regular whole blood donation resulted in a significant reduction in serum PFAS levels compared to an observation group. Plasma donation, which allows for more frequent procedures, proved even more effective, achieving up to a 30% decrease in PFOS levels over a year. This demonstrates that regular blood or plasma removal can meaningfully accelerate the body’s natural elimination process, provided the procedure is medically supervised.
Reducing Your Exposure to PFAS Going Forward
Since the body struggles to eliminate PFAS, the most reliable strategy for lowering the body’s burden is to minimize future exposure. Drinking water is a common source of exposure, making filtration a practical, high-impact action. Home filtration units using granular activated carbon (GAC) or ion exchange resins can be effective at removing many PFAS compounds.
High-pressure membrane systems, such as reverse osmosis (RO) units, are considered the most effective for in-home treatment, capable of removing a wide range of PFAS compounds with high efficiency. The effectiveness of GAC can vary, as some short-chain PFAS are more difficult to remove than longer-chain varieties. Testing your water source for PFAS can help determine the necessary level of filtration.
Avoiding PFAS in consumer products is another important step, as these chemicals are widely used for their stain- and water-resistant properties. Consumers should be wary of products advertised as stain-resistant, water-resistant, or grease-resistant. To limit exposure, focus on the following areas:
- Replacing non-stick cookware, which often contains PFAS, with alternatives like stainless steel, cast iron, or glass.
- Avoiding food packaging such as microwave popcorn bags and grease-resistant takeout containers.
- Checking local fish and game advisories before consumption, as PFAS can accumulate in fish from contaminated waterways.
- Limiting use of items like carpets and upholstery advertised as stain-resistant.