Occurrence of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) in N.E. Spanish surface waters and their removal in a drinking water treatment plant that combines conventional and advanced treatments in parallel lines

Abstract

Perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) are two emerging contaminants that have been detected in all environmental compartments. However, while most of the studies in the literature deal with their presence or removal in wastewater treatment, few of them are devoted to their detection in treated drinking water and fate during drinking water treatment. In this study, analyses of PFOS and PFOA have been carried out in river water samples and in the different stages of a drinking water treatment plant (DWTP) which has recently improved its conventional treatment process by adding ultrafiltration and reverse osmosis in a parallel treatment line. Conventional and advanced treatments have been studied in several pilot plants and in the DWTP, which offers the opportunity to compare both treatments operating simultaneously. From the results obtained, neither preoxidation, sand filtration, nor ozonation, removed both perfluorinated compounds. As advanced treatments, reverse osmosis has proved more effective than reverse electrodialysis to remove PFOA and PFOS in the different configurations of pilot plants assayed. Granular activated carbon with an average elimination efficiency of 64±11% and 45±19% for PFOS and PFOA, respectively and especially reverse osmosis, which was able to remove ≥99% of both compounds, were the sole effective treatment steps. Trace levels of PFOS (3.0-21 ng/L) and PFOA (<4.2-5.5 ng/L) detected in treated drinking water were significantly lowered in comparison to those measured in precedent years. These concentrations represent overall removal efficiencies of 89±22% for PFOA and 86±7% for PFOS.

Perfluoroalkyl substances (PFASs) in wastewater treatment plants and drinking water treatment plants: Removal efficiency and exposure risk

“…However, very limited information is available for the various PFASs in DWTPs (Shivakoti et al, 2010;Takagi et al, 2011;Thompson et al, 2011;Eschauzier et al, 2012;Flores et al, 2013). The concentrations of PFOS and PFOA in influent and effluent of WWTPs and tap water around the world are listed in Tables S6 and S7.…”

“…But granular activated carbon (GAC) and reverse osmosis (RO) can remove PFASs completely when GAC is new (Takagi et al, 2011;Flores et al, 2013). To the best of our knowledge, only a few previous studies investigated multiple PFASs levels in different stages of drinking water treatment plants and most of the previous works were mainly focused on PFOA and PFOS (Shivakoti et al, 2010;Takagi et al, 2011;Thompson et al, 2011;Eschauzier et al, 2012;Flores et al, 2013). Therefore, there is still a need to understand the occurrence, fate and removal mechanism of various PFASs in various WWTPs such as membrane bio-reactor (MBR) and Unitank process as well as in DWTPs.…”

Występowanie perfluorowanych związków organicznych w środowisku i fizykochemiczne metody usuwania ich z roztworów wodnych

“…The principle of the process of membrane filtration, based on [52] Nanofiltracja (NF) oraz odwrócona osmoza (RO) to metody skuteczne dla usuwania perfluorowanych związków alifatycznych z wody. Flores w swoich badaniach po czterech dniach prowadzenia NF i RO osiągnął wysoki stopień usuwania PFOS i PFOA wynoszący powyżej 90% [22]. Odwrócona osmoza w tym przypadku okazała się bardziej skuteczna.…”

Degradation of pharmaceuticals by ultrasound-based advanced oxidation process

“…The presence of these types of compounds is reported everywhere from river water to the drinking water at relatively higher concentration and reported to pose threats to aquatic and terrestrial organisms (Jones et al 2005;Kim et al 2007a;Stolker et al 2004;Ternes et al 2002). The two largest contributors of pharmaceuticals to the aquatic environment are believed to be from hospitals and households including both human and & Charuvila T. Aravindakumar cta@mgu.ac.in 1 animal excretion and drain disposal of pharmaceuticals (Asimakopoulos et al 2013;Cabeza et al 2012;Flores et al 2013;Liu et al 2011;Miege et al 2009;Snow et al 2012Snow et al , 2013. High-volume drugs are nonsteroidal anti-inflammatory drugs, cardiovascular drugs, central nervous system drugs, anticancer drugs, respiratory drugs, endocrinology drugs and antimicrobials (Khetan and Collins 2007).…”