Butan-2-ol

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

The skin sensitisation potential of s-butanol was assessed in a study performed according to OECD Guidelines for the Testing of Chemicals No. 406 and in compliance with GLP in male and female Dunkin-Hartley guinea pigs (de Jouffrey, 1997).  In the main study, 10 animals/sex comprised the s-butanol test group and 5 animals/sex comprised the vehicle control group.  The intradermal induction was carried out with 0.1 mL of 5% (w/w) of s-butanol in vehicle (paraffin oil), and epicutaneous induction was performed with 0.5 mL of undiluted s-butanol to the dorsal area under occlusive conditions.  The challenge exposure also was conducted with 0.5 mL of undiluted s-butanol.  Additionally, all animals were dermally exposed to 0.5 mL of 10% w/w sodium lauryl sulphate (SDS) in vaseline 24 hours prior to topical sensitisation of the skin area in order to induce local irritation (s-butanol was shown to be moderately irritating with no necrosis or ulceration of the skin via intradermal injection and non-irritating via the topical application in the preliminary test).  Skin reactions were observed and recorded 1 hour after dermal induction and 24 and 48 hours after the challenge exposure, all according to the grading scale by Magnusson and Kligman. No positive skin reactions were observed in all animals 24 or 48 hours after challenge. Under the experimental conditions and according to the maximization method of Magnusson and Kligman, no cutaneous reactions attributable to the sensitisation potential of s-butanol were observed in guinea-pigs.  Therefore, the results of this study demonstrated that s-butanol showed no evidence of contact skin sensitisation in guinea pigs.

The low potential of s-butanol to cause skin sensitisation is supported by another skin sensitisation test in which no guidelines was followed. The method followed, however, was similar to that of OECD and the study was performed in compliance with GLP. The scoring method of Magnusson and Kligman was followed. The intradermal induction was carried out with 0.1 mL of 0.1% of s-butanol in vehicle (corn oil), and epicutaneous induction was performed with 0.3 mL of 50% of s-butanol to the dorsal area under occlusive conditions.  The dermal challenge exposure also was conducted with 0.1 mL of 25% of s-butanol.  s-Butanol was reported to show no positive responses in rabbits (10/sex) at either 24 or 48 hours after removal of the challenge patches (Price, 1986).

Migrated from Short description of key information:
Skin sensitisation studies on s-butanol in guinea pigs, one of which was performed according to test guidelines, have demonstrated that the compound is not sensitising.

Justification for classification or non-classification

The substance does not meet the criteria for classification and labelling for this endpoint, as set out in Regulation (EC) No. 1272/2008.