What are Perfluoroalkyl Substances?
Perfluoroalkyl substances (PFAS) are a class of man-made, highly fluorine chemicals, that are getting a lot of attention as emerging contaminants. Though there are nearly 4,800 different types of perfluoroalkyl substances, there are two that are commonly focused on because of their use in everyday household products: perfluorooctanoic acid and perfluorooctanesulfonic acid. Perfluorooctanoic acid, also known as PFOA or C8, is a chemical compound with the molecular formula of C8HF15O2. Perfluorooctanesulfonic acid, also known as PFOS, is a chemical compound with the molecular formula of C8HF17O3S. Both are considered stable chemicals, comprised of 8 carbons. The stability of these carbons and fluorine atoms make them extremely persistent in the environment, and difficult to abate.
Where are Perfluoroalkyl Substances like PFOA and PFOS found?
PFOA and PFOS are industrial chemicals widely used, across the globe. Their known for their ability to repel water and other sticky substances, making them ideal for a number of different applications. Common applications include:
- As surface protection for items such as:
- Non-stick cookware
- Carpeting and rugs
- A component in the manufacturing of:
- Food and beverage packaging
- Personal hygiene goods like floss, waxes, and makeup
- Automotive parts and fabrics
- Consumer goods packaging
- Outdoor clothing and gear
- They are also commonly used in manufacturing facilities as:
- Wetting agents
PFOA and PFOS make surfaces resistant to buildup, and easier to clean, making them ideal for many everyday products. Many people are shocked to find out that PFOA and PFOS can be found in just about every room in their home. Recent reports show that it can transfer from surfaces, this includes transferring from non-stick surfaces into the foods, as well as into wastewater when these surfaces are washed.
Perfluoroalkyl Substances are so commonly used, dangerous levels of PFOA and PFOS have been identified in nearly all bodies in the United States, and other industrialized parts of the world, and reaching as far as the arctic. This leads many researchers to believe that Perfluoroalkyl Substances can transport very easily, over wide areas. The concentration of PFOA and PFOS are generally much higher in areas downstream from water and waste processing facilities, pointing towards a direct correlation between human use and this pollution.
Why are PFOA and PFOS a Concern?
These perfluoroalkyl substances have made it onto the emerging contaminants list because of their resistance to environmental degradation, and their confirmed negative effects on animal and plant life, including humans. Because they are often released into the air around manufacturing facilities, higher accumulations of perfluoroalkyl substances have been found in humans and animals living in these areas. Ingestion of food and water that is sourced near these facilities has also shown increased bodily accumulation. Studies have shown these higher levels of accumulation are directly tied to a number of concerning conditions, including liver issues, hypertension, developmental delays, high cholesterol, issues with immune responses, thyroid disease, pregnancy complications, and a number of different cancers. These chemicals have been noted as toxic to animals, showing extreme reproductive and systemic issues, after even short-term exposure. The American Conference of Governmental Industrial Hygienists (ACGIH) has classified PFOA as a Group A3 carcinogen; this means it is a known cancer-causing agent in animals, and highly suspected (unconfirmed) in humans. As for the effect on humans, the World Health Organization (WHO) does classify perfluoroalkyl substances, including PFOA and PFOS, as potential human carcinogens.
PFOA and PFOS Restrictions:
In 2002, published research on the environmental concentrations of perfluoroalkyl substances, and their effects, led to a voluntary reduction of use by US manufacturers. In 2006, eight of the major users of PFOA and PFOS agreed to completely phase out use by 2015. Although the number of facilities producing perfluoroalkyl substances has decreased, the risk of local environmental consumption has not decreased, due to the lack of environmental degradation to previously released emissions. The risk of contamination through household products remains a risk, since facilities across the globe are still using perfluoroalkyl substances in and on their products.
In 2016, the EPA found that the level of perfluoroalkyl substances in nearly all water sources in the United States warranted a recommendation that all water processing facilities take steps to filter and abate the chemicals. In addition, they suggested that all people should use a filtration system of some sort, before drinking or cooking with tap water, to reduce the amount of exposure to perfluoroalkyl substances. The concentration of these chemicals in fish and seafood is also a concern, because of the high concentrations that have been found in their flesh. Although the EPA has not set forth any guidelines regarding the consumption of contaminated fish, the states have begun to.
Firm regulatory guidelines have not been issued regarding perfluoroalkyl substances, yet. However, The EPA does recognize PFOA and PFOS as contaminants of emerging concern, meaning further research may soon lead to new rules and regulations. As mentioned above, states in the North East have begun to implement rulings and recommendations for abatement in processes using and manufacturing PFOS and PFOA. GCES is proud to be collaborating with these states, as well as individual, forward thinking companies, to develop and provide industry leading abatement solutions.
How do we treat PFOA and PFOS?
There are a number of ways to treat PFOA and PFOS. One way is with a Regenerative Thermal Oxidizer. This type of oxidizer uses extremely high heat, about 1500°F, to clean the exhaust of dangerous pollutants and compounds. Developed for large volumes, and low VOC concentration air pollution applications, Regenerative Thermal Oxidizer technology is based on using ceramic media as heat exchangers and switching valves. This design contrasts with Recuperative Thermal Oxidizers which use metallic heat exchanger technology, with primary and/or secondary heat. In a configuration utilizing a secondary heat exchanger, among other distinctions, the outgoing stream (typically fresh air) of the secondary heat exchanger process is routed to another part of the plant for its use or back to the process itself.
Although the RTO is a great option, an important factor to consider is hydrofluoric acid formation as a result of combustion of these compounds. The hydrofluoric acid will likely damage the ceramic media and fiber insulation, over time. In some cases, the concentration will be low enough that the damage can be considered “normal wear and tear.” However, if the concentrations are high, it would likely require specially coated insulation, as well as chemical porcelain ceramic media.
Other options for treating PFOA and PFOS would be a Thermal Recuperative Oxidizer, a Carbon Adsorber, or a Direct Fired Thermal Oxidizer. Regardless of the oxidation technology chosen, the system must include a quench or scrubber, to reduce the dangers of hydrofluoric acid emissions.
Gulf Coast Environmental Systems has been following the EPA’s list of emerging contaminants closely, and we have worked on several pollution control solutions for facilities looking to take steps to reduce their perfluoroalkyl substances emissions. Our commitment to the health of our planet, and all who inhabit it, make projects like these exciting. We look forward to the continued opportunities to reduce the amount of perfluoroalkyl substances released into the environment. If you are interested in perfluoroalkyl substance abatement solutions, please contact us at email@example.com or 832.476.9024