Publication of GB mandatory classification and labelling (GB MCL) Agency Opinions

The next batch of GB MCL Agency Opinions are now available for download.

A GB MCL Agency Opinion formally proposes the GB MCL for chemical substances, based on the scientific and technical assessment of the scientific data in line with the GB CLP Regulation, together with an assessment of the policy and socio-economic impacts on the UK.

It sets out whether there is adequate scientific evidence to support a new or revised GB MCL of a substance and what the potential impact of the proposed GB MCL may be.

Download the next batch of Agency Opinions from the GB MCL publication table.

These GB MCL Agency Opinions relate to substances for which HSE (as the GB CLP Agency) published an Agency Technical Report under Article 37 of the GB CLP Regulation in 2024.

At the time of publication, the classification and labelling proposed in these Agency Opinions have not been agreed and/or adopted in Great Britain.

For information on the next steps in the process, please see our webpage on the GB MCL system.

We expect to publish our next batch of Agency Opinions in December 2025. CLP ebulletin alerts will be issued when Agency Opinions are published on the HSE website. 

If you have any questions or feedback on the GB MCL Agency Opinions, please contact us at: GBCLP.GBMCL@hse.gov.uk

Journalists should contact HSE’s press office for further information.

ECHA public consultation

Call for comments

The GB MCL process includes the consideration of information gathered from public consultations, conducted by HSE or international bodies such as the European Chemicals Agency (ECHA). 

ECHA has announced public consultations on the following proposals for harmonised classification and labelling (CLH):

Deadline: 2 January 2026

• propaquizafop (ISO) (EC: -; CAS: 111479-05-1). Pesticide active substance. All hazard classes open for commenting

Deadline: 9 January 2026

• 2,4,6-tris(dimethylaminomethyl)phenol (EC: 202-013-9; CAS: 90-72-2). Chemical registered under REACH. Health hazard classes open for commenting

View the consultation on the ECHA website.

Interested parties are invited to submit comments to the above consultation by the dates specified above. The comments will be published on ECHA's website.

UK-based businesses with an interest in the proposal are strongly encouraged to share any relevant information. 

Scientific and technical information should be submitted directly to ECHA using their commenting webform by the deadlines above. Comments will be published on ECHA's website.

Further information

If your business is affected by the GB CLP Regulation, please also consider if you are likely to be affected by the classification and labelling proposals.

Let us know at an early stage if you anticipate any significant impacts or benefits.

Information on wider policy and impact considerations can be submitted to HSE at GBCLP.GBMCL@hse.gov.uk. 

Under the GB CLP Regulation, HSE will consider published opinions of the Committee for Risk Assessment of ECHA (RAC) before publishing its own Agency Technical Reports and Agency Opinions, so any information you provide will be important in any final GB MCL decision.

More information on the new GB MCL system is available on the HSE website.