Per- and polyfluoroalkyl substances, often referred to as PFAS, are a broad category of synthetic chemicals widely integrated into modern society. Their unique properties made them desirable for numerous industrial and consumer applications. Growing scientific understanding of their widespread presence and implications for environmental systems and human well-being has led to increased public and scientific interest.
What are Per- and Polyfluoroalkyl Substances?
Per- and polyfluoroalkyl substances (PFAS) are human-made organic chemicals defined by a chain of carbon atoms where fluorine atoms are strongly bonded to the carbon backbone. The distinctive carbon-fluorine bond is one of the strongest in organic chemistry, contributing to their exceptional stability and rendering PFAS highly resistant to heat, water, and oil.
Due to this robust carbon-fluorine bond, PFAS are often called “forever chemicals.” They do not easily break down in the environment or within the human body, persisting for extremely long periods. Their development began in the 1930s, with early innovations leading to materials like polytetrafluoroethylene (PTFE), known for its non-stick properties. These early compounds were valued for their ability to repel water and stains, offering novel solutions for various industrial and consumer needs.
Widespread Presence and Sources
PFAS have been incorporated into a vast array of consumer products. Non-stick cookware, such as pans coated with Teflon, historically used PFAS to prevent food from sticking. They are also found in stain-resistant carpets and upholstery, water-resistant outdoor clothing, and some personal care products like cosmetics. Food packaging, including grease-resistant pizza boxes and microwave popcorn bags, has also contained PFAS.
Beyond consumer goods, PFAS have extensive industrial applications. They have been used in chrome plating, electronics manufacturing, and oil and gas recovery. A significant source of environmental contamination has been aqueous film-forming foams (AFFF), specialized firefighting foams used to extinguish flammable liquid fires. PFAS enter the environment through multiple pathways due to these varied uses. Industrial discharges, wastewater treatment plant effluents, and leachate from landfills can release PFAS into water bodies and soil. These chemicals can then travel long distances through water and air, contaminating remote areas.
Impact on Human Health and the Environment
PFAS chemicals demonstrate bioaccumulation, meaning they build up in living organisms over time. When humans are exposed to PFAS, these compounds are absorbed into the body and can remain there for years, accumulating in blood, organs like the liver and kidneys, and even breast milk. This occurs because the body has difficulty breaking down and eliminating these persistent substances.
Their environmental persistence is also significant; once released, PFAS can remain in water, soil, and air for extended periods, contributing to widespread contamination. Their high mobility allows them to travel through groundwater and surface water, affecting drinking water supplies. Scientific studies have linked PFAS exposure to potential health effects in humans. These include impacts on the immune system, potentially reducing vaccine effectiveness. Exposure has also been associated with altered thyroid hormone levels, increased cholesterol, and liver enzyme changes.
Concerns also extend to reproductive health, with studies suggesting connections to decreased fertility and developmental effects in children. Certain PFAS compounds have been linked to an increased risk of specific cancers, such as kidney and testicular cancer. Research into the full spectrum of PFAS health impacts is ongoing, and understanding of these effects continues to evolve as more studies are conducted.
Addressing PFAS: Regulation and Mitigation
Governments and scientific bodies worldwide are actively working to address PFAS contamination. In the United States, the Environmental Protection Agency (EPA) has been developing strategies to regulate PFAS in drinking water and address industrial discharges. Many states have also implemented regulations, setting limits for PFAS in drinking water and initiating cleanup programs for contaminated sites. International agreements and frameworks are also being explored to manage these globally distributed chemicals.
Research is underway to develop technologies for detecting and removing PFAS from water, soil, and air. Remediation methods include advanced filtration systems, such as granular activated carbon and reverse osmosis, which can capture PFAS molecules. Other experimental technologies, such as electrochemical oxidation and high-temperature incineration, are being investigated for their ability to break down the carbon-fluorine bond. Scientists are also focused on developing safer chemical alternatives that can provide similar functional properties without the environmental persistence and health concerns of traditional PFAS.
Individuals can potentially reduce their exposure to PFAS in everyday life. Checking product labels for “PFAS-free” or “PFOA-free” claims when purchasing non-stick cookware, water-resistant clothing, and food packaging is recommended. Using certified water filters designed to remove PFAS from drinking water is another practical measure. Avoiding microwave popcorn bags and opting for stainless steel or cast iron cookware can also reduce potential exposure.