Transport of perfluoroalkyl acids in a water-saturated sediment column investigated under near-natural conditions

The aim of this study was to gain an understanding of the transport of C4-10 perfluoroalkyl carboxylic acids (PFCAs) and C4,6,8 perfluoroalkyl sulfonic acids (PFSAs) in a water-saturated sediment column representing a riverbank filtration scenario under near-natural conditions. Short-chain PFCAs and PFSAs with up to six C-atoms showed complete tracer-like breakthrough. Longer chain ones were retarded due to sorption to the sediment or due to other processes in the aqueous phase. The study reports the first column derived sediment-water partition coefficients ranging from 0.01 cm3 g-1 to 0.41 cm3 g-1 for C4,6 PFSAs and from 0.0 cm3 g-1 to 6.5 cm3 g-1 for C4,5,6,8,9 PFCAs. The results clearly indicate that short-chain PFCAs and PFSAs may pose a problem if contaminated surface waters are used for drinking water production via riverbank filtration.