All PFAS Chemicals are Not the Same

    There are currently a group of chemicals which have been placed in the spotlight and are receiving significant attention. Per-and polyfluoroalkyl substances (PFAS) are being discussed in the media and are constantly referenced as substances that will lead to the next industrial disaster. Some of the information depicted about these can at times be hyperbolic. The Fluid Sealing Association (FSA) is therefore actively trying to give concrete, fact based, knowledge about this subject to counter some of the more hysterical reactions to these issues. One of the major focuses of the FSA is on the chemical Polytetrafluoroethylene (PTFE).

    By Ron Frisard, Global Training Manager, AW Chesterton / Gasketing Chairman of the Fluid Sealing Association

    What are PFAS?

    PFAS are a group of chemicals used to make fluoropolymer coatings and products that resist heat, oil, stains, grease, and water. There are over 4,700 known different chemicals that fit under the umbrella of PFAS. Fluoropolymer coatings are found in a variety of products, including clothing, furniture, adhesives, food packaging, and heat-resistant nonstick cooking surfaces. Many sealing products including valve packing, pump packing, gasketing, and O-rings in mechanical seals also contain Fluoropolymer.

    In order to highlight the vast range of chemicals, one can think of each compound as a different type of cat that exists in the world. Imagine 4,700 felines frolicking in a field. A lion and a tiger tussle at one end. A pair of kittens unravel yarn at the other. And in between, there are 4,696 leopards, pumas, jaguars, lynx, panthers, and house cats. Now imagine 4,700 PFAS per- and polyfluoroalkyl substances— polymers as well as non-polymers, spread across that same field. Some are large molecules. Others are small. Some are bioavailable, some are not. All are PFAS, and just as the felines, come in all shapes, sizes, and ferocity.

    PFAS Chemicals are Not all the Same

    All PFAS chemicals are not equal and should not be regulated as if they are. Each should be treated differently according to its application and toxicity. Umbrella legislation or regulation against all PFAS could end the use of non-harmful PTFE, a protector of people, the environment, and industrial equipment. According to the Organization of Economic Cooperation and Development (OECD), “PFASs are a chemical class with diverse molecular structures and physical, chemical, and biological properties, and it is highly recommended that such diversity be properly recognized and communicated in a clear, specific and descriptive manner. The term ‘PFAS’ is a broad, general, non-specific term, which does not inform whether a compound is harmful or not, but only communicates that the compounds under this term share the same trait for having a fully fluorinated methyl or methylene carbon moiety.”

    Why is PTFE Important?

    PTFE polymers in their finished form are corrosion resistant, save energy, increase safety, and allow easy movement of machine elements. These products are used in infrastructure, aerospace, military, power generation, chemical processing, food, and pharmaceutical industries. Fluid sealing products, including those with PTFE serve an essential role. They improve energy savings, reduce emissions, worker safety, and equipment reliability. The FSA promotes a targeted approach to regulating hazardous chemicals. It generally opposes regulatory overreach, and a one size fits all approach to PFAS chemicals, (would include safe PTFE and other fluoropolymers) as it may lead to unintended consequences for the climate, economy, and safety.

    PTFE materials are “generally regarded as safe” by the FDA and are approved for implantation and various medical devices per USP Class VI designation. In sealing products, PTFE prevents leakage from industrial equipment. Leaks from these assets contribute to greenhouse gas emissions in some applications and create significant safety hazards in others. Seals that utilize PTFE polymers reduce leakage rates to almost zero, making it a cornerstone in the effort to decrease fugitive emissions, battle climate change, and protect workers. In many applications the unique properties of PTFE mean that there is not an acceptable alternative solution.

    Where to find PAFS. Image source http://www.newmoa.org/events/docs/228/PFAS_Sampling_Chiang_Aug2016.pdf

    PFAS Chemicals of Concern

    PFAS chemicals of concern include perfluorooctanoic acid (PFOA) and perfluorooctane sulfonic acid (PFOS). These should be regulated to ensure that they do not entre drinking water or the environment. The thousands of other chemicals, which do not have these detrimental characteristics, should not therefore be grouped into one sweeping regulation or legislative action which may exclude or restrict the use of the safe materials that benefit safety and the environment. Major PTFE manufacturers have removed the use of PFOA from PTFE production processes entirely, eliminating risk and the use of hazardous materials.

    What the FSA Recommends for Legislation of PFAS

    The Fluid Sealing Association recommends that lawmakers use a science-based approach to regulating harmful PFAS chemicals, such as PFOA and PFOS. They also urge regulating bodies to base regulations on standardized test methods and acceptance limits of materials deemed harmful by the EPA. The EPA and other regulating bodies should keep using the grouping concept to distinguish hazardous chemicals from non-hazardous in making determinations; the scope of any regulation should exclude all chemicals deemed non-harmful.

    The FSA is also proposing language in state and federal legislation that would ‘carve out’ PTFE for industry use similar to language for using PTFE in medical usage. This will ensure industry keep running with current PTFE technology.

    FSA’s Mission

    The FSA’s mission is to be recognized as the primary source of technical information; to influence and support the development of related standards and to provide education in the fluid sealing area. To promote a safe, clean environment for society and a safe workplace the employees of the users of sealing products. To monitor the economic, environmental, and social changes which may impact our membership’s business and to maintain a forum for the exchange of this information. FSA supports sensible regulation and legislation to protect the health and safety of our communities and environment.

    ABOUT THE AUTHOR

    Ron Frisard has worked for the A.W. Chesterton Company for the last 30 years in all facets of Mechanical Packing and Gasketing. He is a technical expert in Mechanical Packing and Industrial Gasketing and has traveled over 900,000 miles to customers around the globe. He is currently the Global Training Manager where he manages the design, development, analysis, and execution of training for the company. He has worked with the Fluid Sealing Association for the last 15 years including past chairman of the Packing Division and currently the chairman of the Gasketing division. Ron has also been considered an “industry influencer” and an Industry person of the week by Empowering Pumps and Equipment.