The Stockholm Convention on Persistent Organic Pollutants (POPs) relies heavily on scientific input. The POPs Review Committee (POPRC) is the main scientific body of the Convention, which receives nominations for potential POPs, determines if the substance is a POP that warrants global action, and identifies risk management options. The POPRC then recommends if  the Conference of the Parties (COP) should agree to prohibit or restrict a chemical’s production and use with suggestions on specific cases where short-term ongoing use could be acceptable. Additionally, POPRC conducts other technical work upon parties’ request.

At its twenty-first meeting (POPRC-21), the Committee considered the draft risk profile for polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) and mixed polybrominated/chlorinated dibenzo-p-dioxins and dibenzofurans (PBCDD/Fs). This was the second stage of the review for the Swiss proposal to list these unintentionally produced chemicals, meaning that POPRC members scrutinized scientific data to determine whether global action is warranted. PBDD/Fs and PBCDD/Fs are not intentionally produced but are a by-product of various industrial and combustion processes including waste incineration, metallurgical operations, and thermal processing. These substances are precursors to chlorinated dioxins and furans that are already listed in the Annex C of the Convention.  

POPRC-21 also conducted a significant amount of other technical work, including:

• evaluation of the continued need for perfluorooctane sulfonic acid (PFOS), its salts and perfluorooctane sulfonyl fluoride (PFOSF) for acceptable purposes and specific exemptions;
• review of the specific exemption for the use of perfluorooctyl iodide (PFOI) for the production of perfluorooctyl bromide (PFOB) for the purpose of producing pharmaceutical products;
• consideration on how to support the review of medium-chain chlorinated paraffins (MCCPs), to be undertaken by the COP at its fourteenth meeting in 2029; and
• review of the indicative lists of substances covered by the listings of long-chain perfluorocarboxylic acids (PFCAs), their salts and related compounds, perfluorooctanoic acid (PFOA), its salts and PFOA-related compounds, and perfluorohexane sulfonic acid (PFHxS), its salts and PFHxS-related compounds.

POPRC-21 convened at the Food and Agriculture Organization (FAO) headquarters in Rome, Italy, from 29 September to 3 October 2025.

The Earth Negotiations Bulletin (ENB) writers for this meeting were Anna Dubrova and Jennifer Allan, Ph.D. The Digital Editor was Ángeles Estrada. The Editor was Pam Chasek, Ph.D.