The Expert group on plastic pollution convened by the International Science Council outlines science-based recommendations to inform the final stages of plastics treaty negotiations and a robust and effective instrument.
As governments prepare for the final round of negotiations on a global treaty to end plastic pollution, a newly published Commentary in Nature Sustainability highlights the critical need to embed robust scientific evidence into the treaty’s development and implementation. Authored by the International Science Council’s (ISC) Expert Group on Plastic Pollution, the article offers timely guidance for diplomats and policy-makers ahead of the resumed negotiations (INC-5.2) in Geneva in August 2025.
Titled “Effective progress and implementation of the INC-5 plastics treaty through scientific guidance”, the article outlines science-based priorities to support the development of a global instrument capable of ending plastic pollution and mitigating its widespread impacts on the environment and human health. Convened by the ISC in early 2024, the expert group, comprised of 16 researchers from across diverse regions and scientific fields, was established to provide independent scientific input throughout the treaty process and to support Member States in shaping an effective and inclusive instrument. (https://doi.org/10.1038/s41893-025-01574-0)
The publication follows the inconclusive outcome of the fifth round of negotiations (INC-5) in Busan, which ended without agreement on a treaty text. The authors stress that independent, science-based input is vital to inform the final stage of negotiations, providing a neutral foundation to solving key contentious technical issues and ensuring the treaty is both effective and actionable throughout the implementation phases.
The Commentary presents science-based recommendations on four key elements of the treaty which will determine the treaty’s success:
- A global target to limit production of primary plastic polymers to sustainable levels within a specific time frame, based on scientific indicators and regularly reviewed by a scientific body;
- Global, science-based criteria and lists for harmful chemicals and problematic plastic products, along with clear phase-out timelines;
- A framework for robust monitoring and effectiveness evaluation, supported by globally standardized protocols and open-access data systems to assess the treaty’s effectiveness and ensure transparent, data-driven decision-making;
- A robust science–policy–society interface, grounded in independence, interdisciplinarity, inclusivity and policy relevance, to support decision-making and treaty implementation.
The authors urge Member States to include binding provisions to reduce unsustainable plastic production and and address chemicals and products of concern in plastics, and to adopt inclusive advisory models for integrating interdisciplinary scientific evidence, Indigenous Peoples’ and local knowledge and stakeholder inputs into treaty implementation.
About the ISC Expert Group* on Plastic Pollution
Established in 2024 by the International Science Council (ISC), the expert group brings together global experts from diverse disciplines in marine science, toxicology, circular economy, chemistry, and environmental law. The group provides independent, multidisciplinary scientific input to inform the development of an international legally binding instrument to combat plastic pollution and support evidence-based decision-making.
In this ISC Expert group, IUPAC is represented by Christine Luscombe, Past President of the Polymer Division, and Fani Sakellariadou, Vice President of Chemistry and Environment.
ISC reference
https://council.science/news/nature-comment-plastics-treaty/, published May 26, 2025