A biocide rejected because it could not be determined: the lack of reliable analytical methods led to the non-approval of the quaternary silane generated from dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride — Decision (EU) 2026/1424
Commission Implementing Decision (EU) 2026/1424 of 30 June 2026, published on 3 July, does not approve poly(dimethyloctadecyl[3-(trihydroxysilyl)propyl]ammonium chloride) generated in situ from dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (EC 248-595-8, CAS 27668-52-6) for biocidal products of product-types 2, 7 and 9. According to the ECHA opinions, reliable analytical methods for quantifying and characterising the substance could not be established.
- The substance is listed in Annex II to Delegated Regulation (EU) No 1062/2014 (review programme of existing active substances) with Spain as rapporteur, for product-types 2 (disinfectants not intended for direct application to humans or animals), 7 (film preservatives) and 9 (fibre, leather, rubber and polymerised materials preservatives). Spain submitted its assessment report on 14 September 2012, so the substance was evaluated under the substantive conditions of Directive 98/8/EC; during the work ECHA renamed it as a substance generated in situ.
- The applicant was asked to provide analytical methods, but ECHA considered the data submitted insufficient to quantify and characterise the substance. Without a reliable method, doses and concentrations in toxicological and ecotoxicological studies could not be properly determined and reference values could not be set, so neither the acceptability of risks to health and the environment nor whether the substance is carcinogenic, mutagenic or toxic for reproduction could be concluded.
- Additional data were of poor quality or missing, among others for in vitro and in vivo genotoxicity, reproductive toxicity, carcinogenicity, dermal absorption, acute oral, inhalation and dermal toxicity, sensitisation, toxicokinetics and repeated-dose toxicity. The applicant also failed to submit data on physical and chemical properties within the set deadline.
- Efficacy was not demonstrated: without an analytical method the effective dose could not be established, the tier-2 studies for product-type 2 were not representative of the product’s uses, and for product-types 7 and 9 they were missing. The Biocidal Products Committee adopted three ECHA opinions on 9 September 2025 (ECHA/BPC/488–490/2025); the decision entered into force on 23 July 2026.