Registration Dossier

Administrative data

Description of key information

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not sensitising)
Additional information:

The skin sensitizing potential of 1,4 -Butynediol (B3D) has been examined in 3 well documented GLP and non-GLP OECD 406 guideline (or equivalent) in vivo studies (BG Chemie 1990, Jedrychowski, et. al. 1992, and Hüls AG 1985). In all three studies, B3D did not produce significant skin sensitization. These data are supported by results in human patch testing that, although showing significant skin reactions after challenge applications, failed to reliably demonstrate a sensitizing effect (Kligman, 1966 and GAF, undated).

Migrated from Short description of key information:

Not a skin sensitizer

Justification for classification or non-classification

1,4-Butynediol is classified as a skin sensitizer under Annex I of EU Directive 67/548/EEC and Annex VI of Regulation (EC) 1272/2008. However, this mandatory classification does not appear warranted based on the following two factors: (1) predominantly negative results of three OECD 406 Guideline, or equivalent, studies performed according to the Guinea Pig Maximisation protocol, one of which was performed under GLP conditions and which either showed no positive response or a response rate of <30%, and (2) the results of human patch testing which, although showing significant skin reactions after challenge applications, failed to reliably demonstrate a sensitizing effect.