Alcohols, C12-15-branched and linear

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

The key study was performed using a protocol similar to OECD guideline 406 (maximisation test method) but prior to the introduction of GLP. The test material (Dobanol 25) was diluted in corn oil and used for induction at 0.1% intradermal and 5% occlusive epicutaneous; the challenge application was 2.5% occlusive epicutaneous. No skin reactions were seen in the test or control groups (Clark & Coombs 1978).

 

The Category hypothesis is that the long chain linear aliphatic alcohol family has at its centre an homologous series of increasing carbon chain length, which is associated with a consistency and predictability in the property data across the group, for the physicochemical, environmental and toxicological property data sets. In view of the structural and chemical similarities, it is considered that the results from a number of reliable skin sensitisation studies on single- or multiple-constituent alcohols with appropriate chain lengths can be read across to Alcohols C12-15 branched and linear.

No sensitisation was seen in guinea pig maximisation tests with Dodecanol (Iihama 1997a), Alcohols C12-13 branched and linear (Cassidy 1978c, Sasol 1998e, Vinegar 1976), Tetradecanol (Iihama 1997b), Alcohols C14-15 branched and linear (Biolab 1984c, Cassidy 1978d),

Hexadecanol (Driscoll 1996a) or Alcohols C16-17 branched and linear (Kern 1998). There were no sensitisation reactions in a human repeated insult patch test with Alcohols C16-17 branched and linear (Pagnoni 2003).

A weak sensitisation reaction was seen in a modified Draize test in guinea pigs treated with Decanol, (Sharp 1978) however insufficient data were provided to reach a conclusion on sensitisation. Positive results were recorded in a guinea pig maximisation test with Alcohols C12-13 branched and linear, although some protocol deviations were noted in this study (Ritz 1980). A mouse local lymph node assays (LLNA) performed with Alcohols C14-15 branched and linear and with Alcohols C16-17 branched and linear was also positive, although this study, which has significant deficiencies in terms of methodology and presentation of results, may have been confounded by skin irritation (House 2000). The LLNA studies pre-date the guideline, OECD TG 429, which indicates that for certain classes of substances, the LLNA may give false positives, and refers to Basketter et al (2009). This paper presents information on two fatty alcohols, and concludes that the fatty alcohols are not sensitisers, and may give a true false positive in the local lymph node assay. For such substances, use of the guinea pig maximisation assay is recommended. Data from guinea pig maximisation assays are available for a number of constituents of the substance and for multi-constituent substances with similar composition; the majority of these studies gave clear negative results. Therefore no classification is proposed for sensitisation, and the Category conclusion is that the members of the C6-24 alcohols category are not sensiters.

There is evidence throughout the carbon number range C6-C24 that long chain alcohols are not sensitising; this conclusion does not vary with carbon number within the Category: read-across substances are chosen based on carbon chain length and similarity of physicochemical properties.

Basketter D, Ball N, Cagen S, Carillo JC, Certa H, Eigler D, Garcia C, Esch H, Graham C, Haux C, Kreiling R, Mehling A (2009a). Application of weight of evidence approach to assessing discordant sensitisation datasets: implication for REACH. Reg. Toxicol. Pharmacol., 55, 90-96.

Migrated from Short description of key information:
In a reliable study, using a protocol similar to OECD guideline 406, Alcohols C12-15 branched and linear was not a skin sensitiser in the guinea pig maximisation test (Clark & Coombs 1978). A number of similar studies with related alcohols were also negative (Biolab 1984c, Cassidy 1978c, Cassidy 1978d, Driscoll 1996a, Iihama 1997b, Kern 1998, Sasol 1998e, Vinegar 1976) and no sensitisation was seen in a human repeated insult patch test with Alcohols C16-17 branched and linear (Pagnoni 2003). Some positive results were also with related materials in LLNA (House 2000); these are considered to be false positives.

Justification for selection of skin sensitisation endpoint:
The selected study was conducted according to an appropriate protocol.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information:

The test material contains no structural groups suggestive of respiratory sensitisation and, together with the lack of skin sensitising potential, it is unlikely to be a respiratory sensitiser.

Justification for classification or non-classification

Based on the available data, Alcohols C12-15 branched and linear would not be classified as a skin or respiratory sensitiser under Regulation (EC) No. 1272/2008 (CLP) or Directive 67/548/EEC (DSD). Tests on similar substances included in this category are also supportive of these results, which do not warrant classification for sensitisation under DSD or GHS criteria.