Perfluorinated chemicals (PFCs) are man-made, super chemicals. PFCs have unique properties due to the incredible strength of the carbon-fluorine bond. PFCs have been widely used since 1950 due to their resistance to heat, friction, moisture, oil, and other chemicals. Aerospace, alternative energy, automotive, construction, electronics, military, petrochemical, and other industries rely on the use of PFCs (https://fluorocouncil.com/PDFs/Industrial-Reliance-on-FluoroTechnology.pdf). PFCs are utilized in the production of many everyday consumer products including nonstick cookware, food packaging, cosmetics, furniture, clothing, and carpeting. Fluorochemical-based surfactants in aqueous film-forming foams (AFFFs) block oxygen from feeding fuel fires and prevent the release of flammable fuel vapors. PFCs may be present in various goods as a by-product of manufacturing, as an impurity, or as the product itself.
PFCs have become ubiquitous in the environment because of their stability and wide-spread use. PFCs have been detected in water, soil, air, wildlife, and humans throughout the world. Perfluorinated alkyl acids (PFAAs), especially perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), are the most commonly discussed PFCs in scientific literature and by regulators. PFOS and PFOA were included on the 2009 final contaminant candidate list 3 for consideration under the Safe Drinking Water Act and six PFAAs are currently being monitored under the Unregulated Contaminant Monitoring Rule. Additional regulatory notification rules and other proposed rulemaking has been made by US EPA under Toxic Substances Control Act (TSCA) based on the 2009 long-chain PFC action plan. Long-chain (with carbon chain lengths of eight or greater) PFAAs are bioaccumulative in wildlife and humans and considered toxic to laboratory animals and wildlife, producing reproductive, developmental, and systemic effects in laboratory tests. PFAAs may enter the environment through industrial release (e.g., via effluent, emission, and/or landfill), consumer product use and disposal, application of AFFFs in firefighting and training, and the degradation of larger compounds and polymers that contain a perfluoroalkyl functional group. Other PFCs, including these “precursor” PFCs, are gaining attention of regulators and scientific research. Whereas PFAAs are highly water soluble, neutral PFCs such as perfluoroalkyl sulfonamides (FASAs), perfluoroalkyl sulfonamido ethanols (FASEs) and fluorotelomer alcohols (FTOHs), which are reported to degrade to PFAAs in the atmosphere, are not as water-soluble and are more volatile.
Environmental Standards, Inc. personnel have observed an increase in the frequency regulators request PFAA analyses since 1999, when we were first asked to help in the development of an analytical procedure for the analysis of PFOA by a Fortune 100 client. A handful of commercial laboratories responded to the need for PFAA analysis and developed their own varied, proprietary methodologies. The EPA has since introduced an analytical method for drinking water (EPA 537) and the number of laboratories offering PFAA analysis has been growing. Various procedural differences amongst these laboratories can lead to data quality and comparability issues. Environmental Standards, Inc .personnel have observed differences through auditing and data validation activities of many of the laboratories offering PFAA analysis. Although the laboratories generally use the same instrumentation (LC/MS/MS), there can be significant differences in sample preparation and introduction to the instrument as well as differences in calibration and quantitation techniques. Examples include the strict avoidance of glass versus the use of glass fiber filters, use of materials that may contain PFCs in the laboratory, differences in the parent/daughter transitions monitored, presence or absence of branched isomers in addition to linear isomers in standards, evaluation for branched isomers, and the number and types of isotopes used.
Contact Principal Chemist David R. Blye or Senior Technical Chemist Meg A. Michell at 610.935.5577 to discuss how Environmental Standards can assist you with PFAA analysis needs.