European Chemicals Agency (ECHA) Board of Appeal Upholds Appeal in Developmental Neurotoxicity Study Dispute Under REACH

On May 7, 2026, the Board of Appeal of the European Chemicals Agency (ECHA) issued its final decision in Case A-008-2024 concerning a compliance check under the REACH Regulation for the substance Tris(methylphenyl) phosphate (EC No. 809-930-9; CAS No. 1330-78-5). The appeal was submitted by LANXESS Deutschland GmbH against an ECHA decision requiring submission of a developmental neurotoxicity study under OECD Test Guideline 426. The Board of Appeal concluded that while ECHA retains authority to request additional information during compliance checks under Annex VIII of the REACH Regulation, the Agency lacked the legal basis to specifically require developmental neurotoxicity information through the cited provision in this case. The Board determined that the relevant Annex VIII provision concerns effects observed in repeated dose toxicity studies and does not clearly authorize developmental neurotoxicity testing requirements. The decision further noted that developmental neurotoxicity is specifically addressed under reproductive toxicity provisions in Annexes IX and X of REACH and may also be investigated through substance evaluation procedures under Article 46. As a result, the Board of Appeal annulled the contested ECHA decision and remitted the case back to the Agency for further action.