PFAS River Export Analysis Highlights the Urgent Need for Catchment-Scale Mass Loading Data
Open accessAbstract
Abstract Source apportionment of per- and polyfluoroalkyl substances (PFAS) requires an understanding of the mass loading of these compounds in river basins. However, there is a lack of temporally variable and catchment-scale mass loading data, meaning identification and prioritization of sources of PFAS to rivers for management interventions can be difficult. Here, we analyze PFAS concentrations and loads in the River Mersey to provide the first temporally robust estimates of PFAS export for a European river system and the first estimates of the contribution of wastewater treatment works (WwTWs) to total river PFAS export. We estimate an annual PFAS export of 68.1 kg for the River Mersey and report that the yield of perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) in the catchment is among the highest recorded globally. Analysis of river and WwTW loads indicates approximately one-third of PFOA emitted from WwTWs is potentially stored in the catchment and approximately half of PFOS transported by the River Mersey may not originate from WwTWs. As governments move toward regulation of PFAS in WwTW effluents, our findings highlight the complexity of PFAS source apportionment and the need for catchment-scale mass loading data. This study indicates that strategies for reducing PFAS loading that focus solely on WwTW effluents may not achieve river water quality targets.
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There is a critical need for catchment-scale PFAS loading data.
“One study went as far as to state that there is a critical need for this type of catchment-scale PFAS loading data.16”
The observed PFBS concentration in river Ouse is similar to the 14.9 pg/mL reported for river Mersey in the UK.
“It must be noted that the observed concentration of PFBS in river Ouse are similar to that of 14.9 pg/mL reported for river Mersey in the UK (from August 2022 to July 2023; Byrne et al., 2024)).”
From Occurrence of emerging and persistent organic pollutants in the rivers Cam, Ouse and Thames, UK (2025) · cites this paper as Byrne et al., 2024
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- ■ NOTE ADDED AFTER ASAP PUBLICATION The version of this paper that was published ASAP February 19, 2024, was missing a Supporting Information file (excel file with supporting tables). This was added, and the revised version was reposted February 23, 2014. Environmental Science & Technology Letters pubs.acs.org/journal/estlcu Letter https://doi.org/10.1021/acs.estlett.4c00017 Environ. Sci. Technol. Lett. 2024, 11, 266-272
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- Authors
- Byrne, P., Mayes, W. M., James, A. L., Comber, S., Biles, E., Riley, A. L., & Runkel, R. L.
- Affiliations
- Liverpool John Moores University (GB)
- University of Hull (GB)
- Environment Agency (GB)
- University of Plymouth (GB)
- United States Geological Survey (US)
- Corresponding author
- Byrne, Patrick
- ORCID
- Venue
- Environmental Science & Technology Letters
- Publisher
- American Chemical Society (ACS)
- Published
- 2024-02-19
- Volume
- 11
- Issue
- 3
- Pages
- 266-272
- ISSN
- 2328-8930 (ISSN-L)
- OpenAlex
- W4391942481
- Cited by
- 34
- References
- 41
- Citations by year
- 2026: 18 · 2025: 15 · 2024: 1
- FWCI
- 4.49
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Licence
- Locations
- Environmental Science & Technology Letters (publishedVersion, cc-by)
- Repository@Hull (Worktribe) (University of Hull) (publishedVersion, other-oa)
- Repository@Hull (Worktribe) (University of Hull) (submittedVersion, cc-by)
- Liverpool John Moores University (submittedVersion)
- Funders
- Liverpool John Moores University
- Topics
- Physical Sciences › Environmental Science › Environmental Chemistry › Per- and polyfluoroalkyl substances research
- Physical Sciences › Environmental Science › Pollution › Pharmaceutical and Antibiotic Environmental Impacts
- Physical Sciences › Environmental Science › Environmental Engineering › Urban Stormwater Management Solutions
- Keywords
- per- and polyfluoroalkyl substances, source apportionment, wastewater treatment plants, PFOS, perfluorooctanoic acid, Mersey River, river water quality, PFAS regulation
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