Aquatic predicted no-effect-concentration derivation for perfluorooctane sulfonic acid
Environmental Toxicology and Chemistry
|January 6, 2011
Summary
Perfluorooctane sulfonic acid (PFOS) poses minimal aquatic ecosystem risk, with toxicity thresholds between 0.61-6.66 µg/L. Understanding the toxic mode of action is crucial for accurate risk assessment.
Area of Science:
- Environmental Chemistry
- Ecotoxicology
Background:
- Perfluorooctane sulfonic acid (PFOS) is a widespread anthropogenic pollutant.
- Limited data exists on PFOS toxicity thresholds in aquatic ecosystems.
Purpose of the Study:
- Derive predicted no-effect concentrations (PNECs) for PFOS in aquatic environments.
- Assess the aquatic toxicity risk of PFOS.
Main Methods:
- Utilized four different approaches to derive PNECs.
- Applied the interspecies correlation estimation (ICE) program and final acute-to-chronic ratio (FACR) based on PFOS's toxic mode of action (MOA).
Main Results:
- Recommended aquatic toxicity thresholds for PFOS range from 0.61 to 6.66 µg/L.
- PFOS does not appear to pose a significant threat to aquatic organisms based on PNEC values, microcosm results, and environmental concentrations.
Conclusions:
- Mode of action (MOA) is critical for reliable PNEC derivation.
- The ICE-based species sensitivity distribution (SSD) method is valuable for deriving PNECs with limited toxicological data.
- This study facilitates future research combining QSAR models and ICE for PNEC estimation.
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