Registration Dossier
Registration Dossier
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EC number: 203-698-7 | CAS number: 109-72-8
Endpoint summary
Administrative data
Description of key information
Key value for chemical safety assessment
Additional information
In accordance with column 2 of REACH Regulation 1907/2006/EC Annex VII section 8.5 for substances not fulfilling the criteria of intermediates handled under strictly controlled conditions a study on this endpoint does not need to be conducted if the substance is classified corrosive to the skin.
N-butyllithium is a corrosive and pyrophoric intermediate, manufactured and handled under strictly controlled conditions.
Studies to determine the acute systemic toxicity cannot be performed with n-butyllithium because of its reactivity and corrosive properties (n-butyllithium is classified as corrosive cat. 1B by the registrant). In addition, n-butyllithium is pyrophoric and would react violently (exothermic) on exposure with animal tissues (due to the water content), releasing corrosive lithium hydroxide and likely starting to burn. Therefore the oral toxicity study has also to be waived for animal welfare reasons.
Further, according to an expert statement (iTEConsult. 2011-12-08) there is no need for further classification (read across) for lithium organyles with the same classification as for lithium according to Regulation (EC) No 1272/2008 when they are used undiluted and / or exposure can be excluded due to the applied risk management measures that are stipulated e.g. for a corrosive, pyrophoric intermediate that is handled under strictly controlled conditions.
Thus, for regulatory purposes (registration, C&L) the performance of the oral toxicity study is not technical feasible or in line with animal welfare (corrosive, pyrophoric properties).
Justification for classification or non-classification
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
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