At the end of 2025, several important initiatives were published, including a crucial report that should not be missed. After some delay, the Organisation for Economic Cooperation and Development (OECD) finally published a report on the state of the science on endocrine disrupters under the Globally Harmonised System (GHS). The GHS is a globally recognised UN system which ensures that chemicals are identified and labelled in a systematic way around the world.
The report summarises the results of 1.5 years of work by an ad hoc expert group set up under the OECD which concluded that there is generally a gap in the GHS regarding the identification of endocrine disrupting chemicals (EDCs). In this article, we provide context on why this matters and how the report can contribute to greater protection from endocrine disrupters globally.
The story so far: EU experience on EDCs and adoption of hazard classes in EU law
Despite widespread exposure to EDCs, increasing evidence about the impacts for health and wildlife, and the recognition by the WHO and UNEP that EDCs are of global concern, there are currently no globally agreed hazard classes to identify chemicals with endocrine disrupting properties.
This means there is no international obligation on companies to identify, classify or label substances that have these properties in their products or supply chains. This creates regulatory blind spots in supply chains, where chemicals can circulate internationally without being flagged as endocrine-disrupting on safety data sheets or labels. Any regulatory measures depend on the respective countries/blocs introducing them, and this leads to different levels of protection for people around the world.
The European Union has worked to tackle the problem of identifying EDCs over the last 15 years, and has gained a lot of experience. Building on EDC criteria in the sector of pesticides and biocides that was established in 2017, the EU Commission adopted new hazard classes to identify endocrine disruptors in 2023. This legal change, which entered into force on 1st May 2025, amended the EU’s basic Regulation for the classification, labelling and packaging of substances and mixtures (CLP), and introduced categories for known and suspected EDCs. From this date, it became a legal requirement under the CLP regulation for chemical substances with endocrine disrupting properties sold in the EU to be identified, classified and labelled. This was a world first and marked a big step forward.
GHS committee to decide on identifying EDCs and other hazards at global level
In 2022, the EU presented a proposal to the GHS Sub-Committee of Experts for work to be undertaken on hazard classes not currently addressed by the GHS, including EDC, PBT (persistent, bioaccumulative and toxic) and PMT (persistent, mobile and toxic). The GHS Sub-Committee of experts is an international forum that is part of the GHS, which meets biannually to discuss and decide changes to the GHS system.
The GHS Sub-Committee agreed to include this proposal in its work plan and to convene an informal working group chaired by the EU Commission (called PHI IWG). Several initiatives were subsequently started, including a mandate for technical work on endocrine disrupters that was given to the OECD.
Final report from ad hoc OECD expert group confirms gap in GHS hazard classes
An ad hoc OECD group with expertise on the science and tools for identifying endocrine disruptors was set up, consisting of national experts from EU and non-EU countries, and stakeholder experts including CHEM Trust and scientists from the Endocrine Society.
The OECD experts were tasked with reviewing existing GHS hazard classes that may include endocrine disruptors, identifying gaps in appropriate classification for endocrine disruptors affecting various endocrine pathways, and assessing whether the existing definition of endocrine disruptors as defined by the WHO/IPCS in 2002 is sufficient in the context of the GHS. The experts explored the science and the existing methods available to identify endocrine disruptors for both human health and wildlife.
A key conclusion of the OECD expert group’s work, presented at the GHS Sub-Committee meeting in Geneva in December 2024, was that ‘the group agreed that there is generally a gap in the GHS hazard classes regarding the ability to identify EDs as such, according to the IPCS/WHO definition.’
The final report published in December 2025 gives more details about the work of the group, and Annexes A, B and C provide the details of available methodologies and relevant assays. While the OECD report does not amend the GHS, it provides an authoritative scientific basis for the GHS Sub-Committee to decide whether and how endocrine disruptors could be identified through GHS hazard classes.
Disagreements remain
In an informal document, the US and Canada expressed some disagreement and the need for further discussions. Civil society groups have recently called on the Canadian government to support the inclusion of EDCs in the GHS system.
The UK Government has highlighted domestically that, in their view, the EU has disregarded established international convention by adopting new hazard classes ahead of UN GHS.
The decision-making process requires consensus at the GHS Sub-Committee to act upon the recommendations it receives, so further discussion is needed. The GHS itself is a “building block” system whereby countries can implement the parts of the GHS that they find relevant for their national legislation.
Next steps
As the OECD expert group has published their report, the ball is now back in the court of the PHI-IWG – the GHS working group led by the EU Commission. This group will build on the work of the OECD group, and continue discussions based on additional analysis. Furthermore, the PHI-IWG group will also continue its work on other unaddressed hazard classes, including Persistent, Bioaccumlative and Toxic (PBT) and Persistent, Mobile and Toxic (PMT), which were also added by the EU to its classification and labelling laws at the same time as EDCs.
Michael Warhurst, Executive Director of CHEM Trust, said:
“Science has shown that endocrine disrupting chemicals pose a threat to human health and wildlife. This OECD report is right to identify gaps in the global GHS system for classifying chemical hazards which means that users of chemicals will be unaware of their harmful properties. The EU has made an important step forward by developing and implementing laws in this area, and we would strongly encourage all nations involved in the GHS to support global action on EDCs.
In the meantime, the ongoing implementation of the new ED hazard classes can provide useful input and support for all governments in order to increase the level of protection of their people & wildlife.”
The EU’s chemical agency has recently launched an improved database of chemicals and their properties, including classifications as EDC, PBT and PMT, which is freely available across the world.
