In an article published on March 21, 2017 in the peer-reviewed journal Environmental Science & Technology Zhanyun Wang and colleagues from ETH Zurich, Switzerland, present a global emission inventory of C4-C10 perfluoroalkanesulfonic acids from the life cycle of products based on perfluorooctanesulfonyl fluoride (POSF, CAS 307-35-7) in 1958-2030. Most of the emissions of perfluorooctanesulfonic acid (PFOS, CAS 1763-23-1) occurred between 1958 and 2002, followed by a substantial decrease. This reflects the ongoing efforts to phase out POSF-based products. However, the researchers expect substantial additional releases of these substances until 2030 when the transition period may be completed. Further, they demonstrate that “degradation of side-chain fluorinated polymers in the environment and landfills can be a long-term, (potentially) substantial source of PFOS.”
The current work complements the emission inventory compiled by the same lead author for C4-C14 perfluoroalkylcarboxylic acid (PFCA) substances, published in 2014 in the August and September volumes of the peer-reviewed journal Environment International.
In an article published on March 30, 2017 by regulatory news provider Chemical Watch, reporter Emma Davies summarized the previous and potential future uses of this research by the Organisation for Economic Cooperation and Development (OECD) and other international organizations concerned with managing risks of per- and polyfluoroalkyl substances (PFASs). The published inventories illuminate the levels and trends of PFASs in the environment, what in turn helps to assess the success of phase-out programs.
However, the work on PFAS inventories is impeded by the dearth of data on emission and production. Davies quotes the studies’ lead author, Wang, saying that “a lot of the time we don’t know which compounds are produced.” Wang hopes that the framework developed in his group will provide an incentive to others to fill data gaps and contribute to preparing further inventories. In a review published on February 22, 2017 in Environmental Science & Technology, Wang and colleagues from Sweden and the U.S. highlighted that most research and regulation has so far focused on a limited selection of long-chain PFASs such as PFOS, perfluorooctanoic acid (PFOA, CAS 335-67-1), and their precursors. However, the number of different PFASs which are, or have been, on the global market, is higher than 3,000. The scientists emphasize that “continuing to overlook the vast majority of other PFASs is a major concern for society.”
A large variety of PFASs are used in the manufacturing of food packaging for their anti-stick and fat-repellent properties (summarized in FPF dossier). Examples of food packaging containing PFASs include popcorn bags, fast food packaging in Europe and the U.S., and even the ‘eco-friendly’ bio-based tableware made of sugar cane.
Emma Davies (March 30, 2017). “Researchers build global emission inventory of PFSAs.” Chemical Watch
Wang, Z., et al. (2017). “Toward a comprehensive global emission inventory of C4-C10 perfluoroalkane sulfonic acids (PFSAs) and related precursors: focus on the life cycle of C8-based products and ongoing industrial transition.” Environmental Science & Technology (published March 21, 2017).
Wang, Z., et al. (2017). “A never-ending story of per- and polyfluoroalkyl substances (PFASs)? ” Environmental Science & Technology, 51: 2508-2518.
Wang, Z., et al. (2014). “Global emission inventories for C4-C14 perfluoroalkyl carboxylic acid (PFCA) homologues from 1951 to 2030, Part I: production and emissions from quantifiable sources.” Environment International, 70: 62-75.
Wang, Z., et al. (2014). “Global emission inventories for C4-C14 perfluoroalkyl carboxylic acid (PFCA) homologues from 1951 to 2030, part II: The remaining pieces of the puzzle.” Environment International 69: 166-176.