Scientific scrutiny is central to the work of the Stockholm Convention on Persistent Organic Pollutants (POPs). The main scientific body of the Convention is the POPs Review Committee (POPRC), which receives nominations of potential POPs, determines if the substance is a POP that warrants global action, and identifies risk management options. By the time parties review a chemical for listing in the Convention, this 31-member committee has set out a recommendation that could prohibit or restrict a chemical’s production and use and identifies any cases where short-term ongoing use could be acceptable.

Over its 20-year history, the POPRC has become an exemplar of an effective science body that informs political decision making. While celebrating this anniversary and its achievements, the Committee members took up a wide range of issues.

Switzerland proposed to address the unintentional production of polyhalogenated dibenzo-p-dioxins and dibenzofurans during the production of brominated flame retardants or during fires where such flame retardants are present. The POPRC reviewed this nomination, which was unique because countries usually nominate potential POPs that are intentionally produced.

The Committee also considered risk management evaluations for:

• Chlorinated paraffins with carbon chain lengths in the range C14–17 and chlorination levels at or exceeding 45% chlorine by weight (used as a flame retardant in various PVC products such as floor coverings, cable casings and insulation materials); and
• Chlorpyrifos (a pesticide).

These evaluations set out the case for prohibiting or restricting production and use, and identifying if there are any essential uses where safe alternatives are not available or economically feasible.

Due to its track record of successfully contributing to the protection of human health and the environment from POPs, the POPRC is sometimes tasked with additional work. Along these lines, POPRC-20 considered implementation issues for the Convention, including on the scope of “forever chemicals” perfluorooctanoic acid (PFOA), its salts and PFOA-related compounds listed in the Convention.

Members also debated a report on POPs in stockpiles, products and articles in use, and in wastes. It can be extremely difficult to identify which waste products (from insulation to plastics) contain POPs and which do not. Some products might be recycled, which could re-release POPs into the environment and re-expose people to their dangers. The POPRC is working on options to identify and more safely manage such products.

POPRC-20 convened at the headquarters of the Food and Agriculture Organization (FAO) in Rome, Italy, from 23–27 September 2024.

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