Per- and Poly-Fluoroalkyl Substances in Portuguese Rivers: Spatial-Temporal Monitoring
Open accessAbstract
Eighteen per-and polyfluoroalkyl substances (PFASs) were investigated in surface waters of four river basins in Portugal (Ave, Leça, Antuã, and Cértima) during the dry and wet seasons. All sampling sites showed contamination in at least one of the seasons. In the dry season, perfluorooctanoate acid (PFOA) and perfluoro-octane sulfonate (PFOS), were the most frequent PFASs, while during the wet season these were PFOA and perfluobutane-sulfonic acid (PFBS). Compounds detected at higher concentrations were PFOS (22.6 ng L−1) and perfluoro-butanoic acid (PFBA) (22.6 ng L−1) in the dry and wet seasons, respectively. Moreover, the prospective environmental risks of PFASs, detected at higher concentrations, were evaluated based on the Risk Quotient (RQ) classification, which comprises acute and chronic toxicity. The results show that the RQ values of eight out of the nine PFASs were below 0.01, indicating low risk to organisms at different trophic levels in the four rivers in both seasons, wet and dry. Nevertheless, in the specific case of perfluoro-tetradecanoic acid (PFTeA), the RQ values calculated exceeded 1 for fish (96 h) and daphnids (48 h), indicating a high risk for these organisms. Furthermore, the RQ values were higher than 0.1, indicating a medium risk for fish, daphnids and green algae (96 h).
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PFAS have been widely reported in European surface water, sediment, and biota.
“Across Europe, PFAS have been widely reported in surface water, sediment, and biota [6,7,8,9].”
From Integrated Targeted and Suspect Screening Workflow for Identifying PFAS of Concern in Urban-Impacted Serbian Rivers (2026) · cites this paper as [7]
The Introduction (§1) says PFAS occurrence in surface water has been reported across Europe and identifies sediments among compartments where PFAS have been detected. It discusses bioaccumulation but does not establish that PFAS have been widely reported in European biota, or that reports of sediment occurrence are widespread across Europe. (LLM, conf=0.84)
Experimental — accuracy not yet measuredDifferences in PFAS levels suggest an influence of local point sources, possibly linked to industrial discharges, wastewater effluents, and agricultural runoff.
“Again, it could be said that the differences in levels suggest an influence of local point sources, possibly linked to industrial discharges, wastewater effluents, and agricultural runoff [7].”
From Integrated Targeted and Suspect Screening Workflow for Identifying PFAS of Concern in Urban-Impacted Serbian Rivers (2026) · cites this paper as [7]
In Results and Discussion §2.1.1 (page unavailable), the paper links differences in PFAS levels along the Ave River to a wastewater treatment plant and notes an industrial influence; the Conclusions also identify point-source pressures. Section 2.1.4 says intensive agriculture and industry may explain higher contamination in another river, but the paper does not specifically identify agricultural runoff as a PFAS source. (LLM, conf=0.82)
Experimental — accuracy not yet measuredThe performance characteristics of the instrumental method used in this study were previously validated and described by Barbosa et al.
“The performance characteristics of the instrumental method used in this study were previously validated and described by Barbosa et al. [7].”
From Integrated Targeted and Suspect Screening Workflow for Identifying PFAS of Concern in Urban-Impacted Serbian Rivers (2026) · cites this paper as [7]
The comparative overview of maximum concentrations of targeted PFAS in European surface waters reveals pronounced spatial differences among freshwater systems across Europe.
“The comparative overview of maximum concentrations of targeted PFAS in European surface waters (Table S7) reveals pronounced spatial differences among freshwater systems across Europe”
From Integrated Targeted and Suspect Screening Workflow for Identifying PFAS of Concern in Urban-Impacted Serbian Rivers (2026) · cites this paper as [7]
The Sava River PFAS levels align with findings in other moderately impacted European rivers.
“aligning with findings in other moderately impacted European rivers [7].”
From Integrated Targeted and Suspect Screening Workflow for Identifying PFAS of Concern in Urban-Impacted Serbian Rivers (2026) · cites this paper as [7]
Reports of PFAS in surface waters in Europe indicated PFOS and PFOA as the most frequently detected PFAS compounds.
“Table S8 summarises reports of PFAS in surface waters in Europe which indicated PFOS and PFOA as the most frequently detected PFAS compounds (Barbosa et al., 2023; Junttila et al., 2019; Loos et al., 2010; Pignotti et al., 2017; Sims et al., 2022).”
From Occurrence of emerging and persistent organic pollutants in the rivers Cam, Ouse and Thames, UK (2025) · cites this paper as Barbosa et al., 2023
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References 62 · Cited by 26
Research works printed but not linked: 3
- [6]SC-4/17 Stockholm_Convention, Report of the Persistent Organic Pollutants Review Committee on the Work of Its Fourth Meeting—Addendum to the Risk Management Evaluation for Perfluorooctane Sulfonate United Nations Environment Programme Nairobi, Kenya 2008
- [7]UNEP/POPS/POPRC.14/6/Add.2 Stockholm_Convention, Report of the Persistent Organic Pollutants Review Committee on the Work of Its Fourteenth Meeting—Addendum to the Risk Management Evaluation on Perfluorooctanoic Acid (PFOA), Its Salts and PFOA-Related Compounds United Nations Environment Programme Nairobi, Kenya 2018
- [62]Campo J. Lorenzo M. Pérez F. Picó Y. Farré M. Barceló D. Perfluoroalkyl substance contamination of the Llobregat River ecosystem (Mediterranean area, NE Spain) Environ. Res. 2016 147 503 512 10.1016/j.envres.2016.03.010 24935262 · DOI · Paper page
- Authors
- Barbosa, M. O., Ratola, N., Homem, V., Pereira, M. F. R., Silva, A. M. T., Ribeiro, A. R. L., Llorca, M., & Farré, M.
- Affiliations
- Universidade do Porto (PT)
- Consejo Superior de Investigaciones Científicas (ES)
- Corresponding author
- Llorca, Marta
- Farré, Marinella
- ORCID
- Venue
- Molecules
- Publisher
- MDPI AG
- Published
- 2023-01-26
- Volume
- 28
- Issue
- 3
- Pages
- 1209
- ISSN
- 1420-3049 (ISSN-L)
- PMC
- PMC9921101
- OpenAlex
- W4318200320
- Cited by
- 26
- References
- 62
- Citations by year
- 2026: 10 · 2025: 6 · 2024: 7 · 2023: 3
- FWCI
- 2.24
- Type
- journal article
- Language
- en
- Open access
- gold
- doi.org
- Licence
- Locations
- Molecules (publishedVersion, cc-by)
- PubMed Central (publishedVersion, cc-by)
- PubMed (publishedVersion)
- DIGITAL.CSIC (Spanish National Research Council (CSIC)) (submittedVersion, other-oa)
- DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
- Portuguese National Funding Agency for Science, Research and Technology (RCAAP Project by FCT) (submittedVersion, other-oa)
- Funders
- IMAGE PROJECT (PID2020-116789RB, CEX2018-000794-S, LA/P/0045/2020, UIDB/00511/2020, UIDP/00511/2020, UIDB/50020/2020, UIDP/50020/2020, NORTE-01-0145-FEDER-000069, CEECIND/00676/2017, DL57/2016)
- Spanish Ministry of Science and Innovation (PID2020-116789RB, CEX2018-000794-S, LA/P/0045/2020, UIDB/00511/2020, UIDP/00511/2020, UIDB/50020/2020, UIDP/50020/2020, NORTE-01-0145-FEDER-000069, CEECIND/00676/2017, DL57/2016)
- ALiCE (PID2020-116789RB, CEX2018-000794-S, LA/P/0045/2020, UIDB/00511/2020, UIDP/00511/2020, UIDB/50020/2020, UIDP/50020/2020, NORTE-01-0145-FEDER-000069, CEECIND/00676/2017, DL57/2016)
- LEPABE (PID2020-116789RB, CEX2018-000794-S, LA/P/0045/2020, UIDB/00511/2020, UIDP/00511/2020, UIDB/50020/2020, UIDP/50020/2020, NORTE-01-0145-FEDER-000069, CEECIND/00676/2017, DL57/2016)
- LSRE-LCM (PID2020-116789RB, CEX2018-000794-S, LA/P/0045/2020, UIDB/00511/2020, UIDP/00511/2020, UIDB/50020/2020, UIDP/50020/2020, NORTE-01-0145-FEDER-000069, CEECIND/00676/2017, DL57/2016)
- Project “HealthyWaters—Identification, Elimination, Social Awareness and Education of Water Chemical and Biological Micropollutants with Health and Environmental Implications” (PID2020-116789RB, CEX2018-000794-S, LA/P/0045/2020, UIDB/00511/2020, UIDP/00511/2020, UIDB/50020/2020, UIDP/50020/2020, NORTE-01-0145-FEDER-000069, CEECIND/00676/2017, DL57/2016)
- Scientific Employment Stimulus—Individual Call (PID2020-116789RB, CEX2018-000794-S, LA/P/0045/2020, UIDB/00511/2020, UIDP/00511/2020, UIDB/50020/2020, UIDP/50020/2020, NORTE-01-0145-FEDER-000069, CEECIND/00676/2017, DL57/2016)
- Transitory Norm Programme (PID2020-116789RB, CEX2018-000794-S, LA/P/0045/2020, UIDB/00511/2020, UIDP/00511/2020, UIDB/50020/2020, UIDP/50020/2020, NORTE-01-0145-FEDER-000069, CEECIND/00676/2017, DL57/2016)
- Topics
- Physical Sciences › Environmental Science › Environmental Chemistry › Per- and polyfluoroalkyl substances research
- Physical Sciences › Environmental Science › Health, Toxicology and Mutagenesis › Toxic Organic Pollutants Impact
- Physical Sciences › Environmental Science › Water Science and Technology › Fluoride Effects and Removal
- Keywords
- per- and polyfluoroalkyl substances, PFAS contamination, surface water contamination, river water quality, seasonal variation, perfluorooctanoic acid, PFOS, PFBS, risk quotient, ecotoxicity, fish, daphnids, green algae
- MeSH terms
- Alkanesulfonates, Animals, Caprylates, Environmental Monitoring, Fishes, Fluorocarbons, Portugal, Prospective Studies, Water Pollutants, Chemical, Alkanesulfonic Acids, Rivers
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