How Stockholm Convention Lists PFAS
The Stockholm Convention on Persistent Organic Pollutants provides an international treaty framework for eliminating or restricting chemicals that are persistent, bioaccumulative, toxic, and subject to long-range environmental transport. PFAS meeting these criteria can be listed in Annexes A (elimination), B (restriction), or C (unintentional release reduction) through a scientific evaluation process by the Persistent Organic Pollutants Review Committee (POPRC).
PFOS was listed in Annex B (restriction) in 2009 with specific exemptions for essential uses. PFOA was listed in Annex A (elimination) in 2019 with time-limited exemptions. PFHxS (perfluorohexane sulfonic acid) was added to Annex A in 2022. The POPRC evaluates several additional PFAS as candidates for future listings, including long-chain perfluorocarboxylic acids and their precursors.
Implementation Challenges
Convention implementation is the responsibility of individual Parties — the 184+ signatory countries. Implementation quality varies enormously: developed countries with established chemical regulatory infrastructure can implement relatively quickly, while developing countries often face capacity and resource constraints that delay or limit implementation.
The Stockholm Convention Global Monitoring Plan tracks PFAS levels in human blood, breast milk, and environmental matrices across participating countries to evaluate whether the Convention is achieving its objective of reducing global human and environmental PFAS exposure. Monitoring data demonstrate declining PFOA and PFOS trends in countries with effective implementation while showing continued high levels where implementation lags.
Future PFAS Listings and Emerging Issues
The POPRC’s PFAS work program continues with evaluation of multiple additional compounds and compound groups. The concept of listing entire PFAS classes rather than individual compounds — mirroring the EU universal restriction approach — is being discussed within the Convention framework but faces resistance from countries with significant PFAS manufacturing interests.
The intersection of climate change and PFAS governance is emerging as a policy priority: PFAS applications in energy transition technologies (solar panels, lithium-ion batteries, hydrogen fuel cells) may create tensions between PFAS elimination objectives and clean energy deployment goals. Navigating these tensions requires nuanced essential use frameworks rather than blanket restrictions.