Assessing per- and polyfluoroalkyl substance (PFAS) exposure from cell phone contact

Abstract

Per- and polyfluoroalkyl substances (PFAS) are found throughout the environment and can adversely affect human health. In this study, we monitored PFAS on cell phones to understand whether cell phones contribute to human PFAS exposure through dermal adsorption and hand-to-mouth exposure. Cell phone (n=118) and hand wipes (n=50) were collected in Ontario, Canada and each sample was paired with a participant lifestyle survey. Wipes were analyzed for 25 PFAS using liquid chromatography tandem mass spectrometry (LC-MS/MS). The analytes included perfluorinated carboxylic acids (PFCAs), perfluorinated sulfonic acids (PFSAs) and polyfluorinated phosphate esters (PAPs). PFAS were detected on 99.2% of cell phones and 100% of hand wipes. The 6:2 disubstituted polyfluorinated phosphate ester (6:2 diPAP) was detected most frequently on both cell phone and hand wipes. The range of ∑PFAS was <MDL to 65.5 ng on cell phones and 0.1 to 259 ng on hands. The median estimated dermal adsorption was 15.3 and 3.1 ng per day from hands and cell phones, respectively. The median estimated hand-to-mouth exposure was 0.93 and 0.49 ng per day from hands and cell phones, respectively. While cell phone wipes may offer supplementary information, the findings suggest that hand wipes remain the preferred matrix for accurate exposure assessment. Cell phones were demonstrated to be an additional source of exposure to perfluorohexanoic acid (PFHxA), perfluorooctanoic acid (PFOA), 8:2 monoPAP, 6:2 diPAP, and 6:2/8:2 diPAP. PFAS exposure was also correlated with age (14–65+), education, race, and continent of birth, based on lifestyle survey findings. Our results point towards diverse and multi-factor exposure pathways for the examined PFAS.