April 13, 2026 by Rhiannon Smith

Following Brexit, the EU chemical regulation (REACH – Registration, Evaluation, Authorisation, and Restriction of Chemicals) was mirrored in the UK as UK REACH. In May to July of 2024, the UK government opened a consultation on the ATRm (alternative transitional registration model) – amendments to the information requirements for UK REACH registrations of substances previously registered under EU REACH. The proposal was that the information requirements for these substances are significantly reduced and would rely mainly on the published summaries available via the ECHA dissemination portal, though the UK regulators would have the ability to request additional information should they deem this necessary.

The UK Government Department for Environment, Food and Rural Affairs (Defra) have now published the outcome of this consultation. Based on this outcome, the information requirements for substances covered under the ATRm will be split on the basis of tonnage band (≥1 – <10 or ≥10 tonnes per year (tpa)) and hazard classification of the substance, as follows:

• Full registrations at 1-10 tpa and intermediate registrations at any tonnage band: Classification
• Full registrations at >10 tpa for non-classified substances: Classification, PNECs and DNELs
• Full registrations at >10 tpa for classified* substances: Classification, PNECs and DNELs, physico-chemical properties (physical state, melting point, boiling point, vapour pressure, octanol-water partition coefficient, water solubility, biodegradability) and risk assessment as part of the Chemical Safety Assessment (CSA)

* Classified substances are those that meet the classification, labelling and packaging (CLP) criteria for explosive, oxidising, flammable, pyrophoric, chemically unstable gases, aerosols, substances which in contact with water emit flammable gases, organic peroxides, acute toxicity, skin or eye irritation/corrosion, sensitisation, mutagenicity, carcinogenicity, reproductive toxicity (fertility or development), specific target organ toxicity following single or repeat exposure, aspiration hazard, hazardous to the aquatic environment, hazardous to the ozone layer, PBT (persistent, bioaccumulative, toxic), vPvB (very Persistent, very Bioaccumulative).

In contrast to the originally proposed ATRm, the consultation outcome has confirmed that additional use and exposure information will not be required under UK REACH. Instead, the use and exposure information will remain in line with that required under the existing UK REACH regulation (i.e. in line with the requirements for EU REACH).

In the outcome from the consultation, Defra also confirmed that registrants should join substance groups to facilitate agreement of hazard conclusions, the sharing of data and, if relevant, any costs associated with the joint submission of that data. These will operate in a similar way to the EU’s ‘Substance Information Exchange Fora’ (SIEFs).

If you have any questions on UK REACH or if we can assist you with this in any way, please contact us.