PFAS Research Advances Shed Light on Environmental Contamination

Scientific studies have identified PFAS, or per- and polyfluoroalkyl substances, as persistent environmental contaminants found in a wide range of settings. Ongoing research is focused on understanding how these chemicals spread and developing techniques to detect and remove them from the environment.

PFAS have been produced and used for decades in items such as nonstick cookware, waterproof clothing, firefighting foams, food packaging, and cosmetics. Their strong carbon-fluorine bonds make them resistant to natural breakdown, resulting in accumulation in water, soil, air, food, and human blood. These chemicals have been detected across the globe, including in remote regions and in wildlife.

Multiple exposure routes to PFAS have been identified, including ingestion through contaminated food and water, inhalation of indoor and outdoor air, and skin contact with treated products. Laboratory studies have shown that human skin tissue can absorb substantial amounts of PFAS, with certain compounds reaching up to 60% absorption after prolonged exposure.

PFAS contamination in marine environments can originate from sources such as landfills, airport runways, farm fields, and failing septic systems. In some locations, including Miami’s Biscayne Bay, urban canals have been identified as major contributors. Surface water near land has been found to contain PFAS concentrations nearly six times higher than offshore waters, increasing exposure risks for marine organisms living near the surface.

What the numbers show

• PFAS exist in over 10,000 forms, with only a small fraction tested for toxicity
• Lab-grown human skin tissue absorbed up to 38% of PFOA and nearly 60% of some short-chain PFAS
• Rice University’s method achieved 99.98% removal of PFOA and over 96% defluorination
• University of Adelaide’s process broke down PFOS by nearly 99% using visible light
• University of Cambridge study found certain gut microbes expelled up to 75% of long-chain PFAS in mice

Research in Norway has shown that PFAS can travel long distances through the atmosphere, carried by sea spray before returning to land. This atmospheric transport helps explain their widespread presence even in remote environments, including polar regions. Only a small proportion of the many PFAS compounds have been studied for their health effects, and most remain uncharacterized.

Several recent studies have focused on methods to remove or break down PFAS. The University of Missouri-Columbia published findings that heating PFAS with granular activated carbon at about 572°F can convert about 90% of the chemicals into inorganic fluorine. Rice University researchers developed a flash joule heating technique that, when combined with mineralizing agents, resulted in over 96% defluorination and nearly complete removal of PFOA, while also converting the carbon material into graphene.

The University of Adelaide reported using a photocatalytic material activated by visible light to degrade PFOS by nearly 99%, producing fluoride and potentially reusable byproducts. Another approach from the University of Cambridge found that certain gut microbes in mice could absorb and expel up to 75% of long-chain PFAS, suggesting possible future applications for probiotic treatments.

Advances have also been made in PFAS detection. Researchers developed an electrochemical sensor using two-dimensional aluminium quasicrystal, which can detect PFOA at sub-picomolar concentrations. In addition, a deep-learning geospatial framework has been created to predict PFAS contamination in surface water using environmental and land-use data.

* This article is based on publicly available information at the time of writing.