Guideline on the determination of Perfluoroalkylated substances (PFAS) in seawater.

Abstract

Perfluorooctane sulphonic acid (PFOS), perfluorooctanoic acid (PFOA) and other per- and polyfluoroalkyl substances (PFASs) are considered global environmental contaminants. PFOS and PFOA are chemically and biologically inert and very stable (Poulsen et al. 2005). PFOS meets the P (persistent) and vP (very persistent) criteria due to very long half lifes. PFOS is also bioaccumulative (B) and toxic (T) (OSPAR 2005). PFOA is considered as very persistent (vP) and toxic (T), but not bioaccumulative (Van der Putte et al. 2010). Both have the capacity to undergo long-range transportation. These guidelines concentrate on the sampling, extraction and instrumental analysis of per- and polyfluoroalkyl substances (PFASs) from seawater and also address special aspects of the sampling matrix. Currently, there are no HELCOM monitoring guidelines for PFASs in biota and sediments but information can be found in Ahrens, L., Vorkamp, K., Lepom, P., Bersuder, P., Theobald, N., Ebinghaus, R., Bossi, R., Barber, J. L., McGovern, E. 2010. Determination of perfluoroalkyl compounds in water, sediment, and biota. ICES Techniques in Marine Environmental Sciences No. 48. 16 pp. These guidelines provide advice for the analysis of per- and polyfluoroalkyl substances in total seawater which basically includes the following steps: i) sampling, ii) extraction and clean-up, and iii) instrumental analysis and quantificationThe extraction and preconcentration of the PFASs is a crucial step in the procedure as the expected concentrations in seawater are often only in the pg L-1 range. Extraction and enrichment are usually conducted through solid phase extraction (SPE).