Comparing measured and modelled PFOS concentrations in a UK freshwater catchment and estimating emission rates

Abstract

Contact CEH NORA team at noraceh@ceh.ac.ukThe NERC and CEH trademarks and logos ('the Trademarks') are registered trademarks of NERC in the UK and other countries, and may not be used without the prior written consent of the Trademark owner. Convention and largely restricted in Europe. It continues to be detected in aquatic 18 environments, with only limited studies into the on-going sources. This paper explores PFOS 19 emissions discharged by the general population into a small catchment comprising of two 20 rivers in the UK. A sampling campaign was undertaken to improve our understanding of 21 population-derived PFOS sources from sewage treatment plants (STPs) and in rivers. A 22 corresponding modelling exercise allowed an emission estimate of 13 µg/day/per capita to be 23 derived for the Aire and Calder rivers. PFOS emission was linked to STP discharges, and 24 thereby population density, by using a correlation with the artificial sweetener sucralose, a 25 conservative chemical marker for waste water (R 2 = 0.69). The model was able to accurately 26 estimate the spatial trends of PFOS in the rivers, while predicted concentrations were within a 27 factor of three based on per capita emission values taken from the literature. Measured PFOS 28 concentrations in rivers suggested that emissions from STPs are partially dependent on 29 treatment type, where plants with secondary or tertiary treatment such as activated sludge 30 processes emit less PFOS, possibly due to increased partitioning and retention. With 31 refinements based on the type of treatment at each STP, predictions were further improved. 32 2 The total PFOS mass discharged annually via rivers from the UK has been estimated to be 33 between 215 and 310 kg, based on the per capita emissions range derived in this study. 34 1 Comparing Measured and Modelled PFOS Concentrations in a UK

Contamination risk of raw drinking water caused by PFOA sources along a river reach in south-western Finland

“…2 l). The measured PFOS concentrations were considerably higher than the PFOA concentrations in our study: from b LOQ (0.3 ng/l) to 20.7 ng/l (Earnshaw et al, 2014) and 1.5-7.3 ng/l (Miyake et al, 2014). Thus the uncertainty from sample analysis was likely lower in these studies.…”

“…Methods that have been used to assess the importance of different PFAA sources include mass balance calculations (Filipovic et al, 2013;Scott et al, 2010;Takazawa et al, 2009), modeling applications (Earnshaw et al, 2014;Paul et al, 2012), and estimation of correlations between PFAA concentrations and for example population or catchment surface area (Müller et al, 2011;Murakami et al, 2008;Pistocchi and Loos, 2009;Takazawa et al, 2009). Different studies place varying emphasis on the importance of the known PFOA sources: communal wastewater treatment plants (CWWTPs) (Becker et al, 2008;Müller et al, 2011;Perkola and Sainio, 2013;Yu et al, 2009), industrial WWTPs (Murakami et al, 2008;Pistocchi and Loos, 2009;Takazawa et al, 2009) and atmospheric deposition (Filipovic et al, 2013;Scott et al, 2010) have all been reported to be major PFOA sources.…”

A review of the pathways of human exposure to poly- and perfluoroalkyl substances (PFASs) and present understanding of health effects

“…For PFOS, wastewater is thought to account for approximately 85% of releases on a continental scale, while industrial sites can be most significant at the local scale. 64, 65…”

North Atlantic Deep Water formation inhibits high Arctic contamination by continental perfluorooctane sulfonate discharges

“…On the continental scale, wastewater is thought to account for the majority of PFOS releases (~85%) to the environment [Buser and Morf, 2009;Earnshaw et al, 2014]. Atmospheric emissions of unstable PFOS precursors can also occur during chemical manufacturing but are estimated to account for only 1% of total inputs to the ocean [Armitage et al, 2009a].…”