Occurrence and infant exposure assessment of per and polyfluoroalkyl substances in breast milk from South Africa
By Linda R Macheka, Ovokeroye A Abafe, Liziwe L Mugivhisa, and Joshua O Olowoyo
November 2, 2021
The exposure of infants to per and polyfluoroalkyl substances (PFAS) through breast-feeding is of global concern owing to their numerous detrimental health effects. This study investigated the occurrence of eleven perfluorocarboxylic acids (PFCAs) and four perfluorosulfonates (PFSAs) in breast milk of nursing mothers from South Africa. The concentrations of PFAS in these samples were measured by using a validated UHPLC - MS/MS method. The median concentrations of Σ15 PFAS ranged from <LOQ - 0.420 ng mL-1, with PFCAs frequently detected in breast milk than PFSAs. However, perfluoropentanoic acid (PFPeA) accounted for 28% of total PFAS concentrations in all samples, the median concentrations of PFUdA, PFDoA and PFTrDA were at par with those of PFOA. The estimated feeding frequency and infant sex but not birth weight and gestation period, were strongly correlated with the body-burden of some short- and long-chain PFAS in breastmilk. On the average, the EDI and HQ of PFOA and Σ4 PFAS (PFOA, PFNA, PFHxS & PFOS) but not PFOS present significant risk to exclusively breastfed infants in South Africa. The results of this study reflect the widespread occurrence of short chain (i.e., C < 6) and long chain (i.e., C11 - C13) PFAS and provide preliminary data for future human biomonitoring of PFAS and other persistent organic pollutants in South Africa, and indeed the African continent.