A 20-year study reveal decrease in per- and polyfluoroalkyl substances (PFAS) in a pelagic seabird from the Western
Ruifeng Lu1, Pere Colomer-Vidal2, Juan Muñoz-Arnanz2
1State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China.
Environmental Pollution (Barking, Essex : 1987)
|September 26, 2024
Summary
European regulations have significantly reduced per- and polyfluoroalkyl substances (PFAS) by 77% in Mediterranean shearwaters over 20 years. Despite declines, shifts to substitute chemicals like PFTrDA highlight ongoing environmental challenges and the need for global cooperation to mitigate PFAS.
Area of Science:
- Environmental Science
- Ecotoxicology
- Marine Biology
Background:
- Per- and polyfluoroalkyl substances (PFAS) are persistent environmental pollutants with global distribution.
- Regulatory actions, including the 2009 ban on perfluorooctane sulfonic acid (PFOS), aim to reduce PFAS contamination.
- The long-term effectiveness of European regulations on PFAS levels in marine ecosystems remains under investigation.
Purpose of the Study:
- To assess temporal trends and levels of 19 PFAS compounds in Scopoli's shearwaters from the Mediterranean basin (2003-2022).
- To evaluate the impact of regulatory measures on PFAS accumulation in marine wildlife.
- To identify shifts in PFAS profiles and potential substitute chemicals.
Main Methods:
- Analysis of 19 PFAS compounds in liver tissues of 62 Scopoli's shearwaters.
- Temporal trend analysis of PFAS concentrations from 2003 to 2022.
- Statistical analysis, including Principal Component Analysis (PCA), to identify patterns and shifts in PFAS composition.
Main Results:
- Overall PFAS concentrations in shearwater livers decreased by 77% over two decades.
- Perfluorooctane sulfonic acid (PFOS) was frequently detected, but perfluorotridecanoic acid (PFTrDA) and perfluoroundecanoic acid (PFUnDA) also showed significant presence.
- A notable shift from PFOS to perfluoroalkyl carboxylic acids (PFCAs) was observed, with PFTrDA temporarily surpassing PFOS after 2009, indicating regulatory substitution effects. Odd-numbered, long-chain PFCAs accumulation trend was observed.
- PCA revealed a clear shift in PFAS patterns from PFOS dominance towards PFCAs over the study period.
Conclusions:
- European PFAS regulations have led to significant overall reductions in environmental contamination, as evidenced by declining PFAS levels in marine birds.
- The study highlights the complex interplay between regulations, chemical substitution (e.g., PFTrDA replacing PFOS), and evolving PFAS profiles in the environment.
- Despite declines, the persistent presence of various PFAS necessitates enhanced international cooperation to address emissions from both regulated and unregulated sources to protect marine ecosystems.
