Dangers of Per- and Polyfluoroalkyl Substances (PFAS)
You’ve likely used or handled consumer products, such as nonstick cookware, pizza boxes, and stain-resistant fabrics, that contain per- and polyfluoroalkyl substances (PFAS). PFAS are a diverse group of man-made chemicals that don’t readily break down and can be found in food, commercial household products, workplaces, drinking products, and living organisms. There is mounting evidence that PFAS exposure is unavoidable and can lead to adverse health effects in humans.
PFAS compounds are identified by signature elemental bonds of fluorine and carbon (an extremely strong bond), and are heat, water, and oil resistant. The most common and most studied PFAS are perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS). PFAS have been manufactured and used in a variety of industries since 1940s but were not widely documented in environmental samples until the early 2000s. They are used in hundreds of industrial processes and consumer products. The four major sources of PFAS are:
- Fire training/fire response sites
- Industrial sites
- Wastewater treatment plants/biosolids
These and other sources of PFAS have resulted in many releases to the environment. Subsequent exposure to and accumulations of PFAS in the human body may lead to increased cholesterol levels, effects on the immune system, low infant birth weights, and potentially cancer.
Regulatory Guidance for PFAS
Currently there are no federally enforceable standards for PFAS contamination in drinking water. In 2016, the EPA issued Lifetime Health Advisories (LHAs) for PFOA and PFOS of 70 nanograms per liter (ng/l, equivalent to 70 parts per trillion) in drinking water for each substance as well as combined. Several states have set guidance values for additional compounds (including PFNA, PFHxS, and PFBS).
The Toxic Substances Control Act (TSCA) allows the EPA to issue Significant New Use Rules to some of the PFAS compounds, allowing limited uses in selected industries and for certain applications. Several states (including Alaska, Maine, Michigan, North Carolina, and Texas) have established standards and guidance values for PFAS in drinking water and groundwater. Australia, Canada, and Western Europe have established polyfluoroalkyl substances in water and soil values.
Solid Waste Disposal
Some states require treatment of PFAS-contaminated soil at a RCRA-permitted incinerator. Since the characteristics of PFAS compounds vary, the estimated temperature to destroy the compounds also varies from approximately 300°C to greater than 1,000°C. Incineration is often the only viable disposal option for media contaminated with polyfluoroalkyl substances. Disposal of PFAS-contaminated soil in landfills may add to the PFAS contaminant load in the landfill leachate.
Liquid Waste Management
Many PFAS compounds can be treated by passing through special granulated media, including granular activated carbon (GAC), biochar, and ion exchange. The GAC adsorption capacity varies based on the type of PFAS compound, and breakthrough times depend on the length of the carbon chain. Breakthroughs are faster for short-chain PFAS. Biochar properties are comparable to GAC systems.
Currently there are no full-scale treatment systems in place for the removal of PFAS. Research indicates that biochar is effective in ultrapure water; however, when treating river water biochar is ineffective compared to GAC and ion exchange. The spent GAC and biochar requires disposal by incineration. Ion exchange has higher adsorption capacity for some PFAS and faster reaction kinetics than GAC. The breakthrough times depend on the PFAS compounds (their chain length and functional groups). Spent single-use media requires incineration or other treatment for disposal. Ion exchange regenerable media can be reused.
Other liquid waste management includes precipitation/flocculation/coagulation, redox manipulation, and membrane filtration.
We Can Help
PFAS can have harmful effects on the environment and human health and should be managed and disposed of properly. The experts at Triumvirate Environmental can assist with your PFAS waste disposal needs. Contact our team today.