In an article published on March 14, 2017 in the peer-reviewed journal Food Chemistry, Itsaso Zabaleta and colleagues from the University of the Basque Country, Bilbao, Spain report on screening, identification, and quantification of per- and polyfluoroalkyl substances (PFASs) in microwave popcorn bags.
Investigated bags were purchased in Europe (Spain, France, Austria, The Netherlands, Hungary, Germany, Italy, Ireland, Czech Republic, Sweden, United Kingdom, and Portugal), America (Mexico, Brazil, and U.S.), and Asia (China and India) during 2015-2016. All bags obtained were manufactured in the country of purchase.
For extraction and high accurate mass spectrometry-based analysis, the authors applied and further developed the procedures that they have described in 2016. They measured various PFASs including polyfluoroalkylphosphates (PAPs) and their intermediate and end degradation products. PAPs are of concern because they are potential precursors of perfluorocarboxylic acids (PFCAs), such as perfluorooctanoic acid (PFOA) or perfluorononanoic acid (PFNA), which are highly persistent. Thus, continuous manufacturing of PAPs contributes to further accumulation of PFCAs in the environment, wildlife, and humans.
Up to 46 different fluorinated substances could be identified and quantified in different samples, including several intermediates of PFCA precursors, namely the fluorotelomer saturated acids (FTCAs) and fluorotelomer unsaturated acids (FTUCAs) of different chain lengths. These findings lend further support to the link between PAPs and PFCAs.
In European and American samples, the short-chain PFCAs (C4-C8) and their precursors were found to be predominant, thus reflecting the ongoing efforts to replace the long-chain PFCAs (C8-C16). On the contrary, Asian samples, especially those from China, still contained high levels of long-chain PFCAs. Noteworthy, a recent study in mice has shown that not only long-chain but also the short-chain PFCAs are being taken up and accumulated in different organs in the body (FPF reported). The toxicological hazards of short-chain PFCAs have not been studied in detail and may require further investigation to ensure safety.
FPF dossier (July 7, 2016): “Per- and polyfluoroalkyl substances (PFASs).” DOI:10.5281/zenodo.57198 (pdf)
Buck, R.C., et al. (2011). “Perfluoroalkyl and polyfluoroalkyl substances in the environment: Terminology, classification, and origins.” Integrated Environmental Assessment and Management 7: 513-541.
Zabaleta, I., et al. (2017). “Screening and identification of per- and polyfluoroalkyl substances in microwave popcorn bags.” Food Chemistry 230: 497-506.
Zabaleta, I., et al. (2016). “Fast and simple determination of perfluorinated compounds and their potential precursors in different packaging materials.” Talanta 152: 353-363.