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 UVCB substance to be registered is a mixture of the two Guerbet alcohols 2 -hexyldecan-1-ol & 2-octyldodecan-1 -ol and their corresponding esters with C12 and C14 fatty acids. Skin sensitization studies are not available for the UVCB substance. The skin sensitizing potential is evaluated on the basis of experimental data for Guerbet alcohols and esters of branched alcohols with fatty acids.

Of these two substance classes present in the UVCB substance, the Guerbet alcohols are considered to have the higher impact on the toxicological evaluation, for the following reasons:

-      The two Guerbet alcohols are the major components in the UVCB substance, accounting for appr. 30-50%

-      The ester components are expected to be metabolized to fatty acids and the two free Guerbet alcohols, thus contributing to the fraction of Guerbet alcohols

-      In comparison to the Guerbet alcohol esters, the free Guerbet alcohols have a lower molecular weight, which would favor their uptake (a prerequisite for the induction of skin sensitizing effects)

-      Having a free functional group, the Guerbet alcohols are more prone to undergo physiological reactions

Data on skin sensitisation are presented for 2 -octyl-dodecanol, a mixture of the two C20 isomers 2-octyldodecan-1-ol and 2 -hexyltetradecan-1-ol, and the reaction product of 2-ethylhexanol with C8-16 fatty acids. The latter is a close homologues to the esters in the UVCB substance, with a very similar fatty acid pattern, but an alcoholic structure which differs in the chain length (close homologue: C8 branched alcohol, esters in the UVCB substance: C16 or C20 branched alcohol). Due to these minor structural variations, the data for the close homologue can be considered for the evaluation of the skin sensitization potential of the ester components in the UVCB substance.

All tested substances exhibited no skin sensitising effects in Guinea pig maximization tests. Additional information is available for the category of Guerbet alcohols, as the REACH consortium in charge has evaluated the sensitization potential of the whole category on a broader data basis. It was concluded that the category of Guerbet alcohols is not suspected to induce skin sensitisation.

Altogether, no skin sensitizing potential is expected for Guerbet alcohols and their esters with C8 -16 fatty acids on the basis of all available information.

Justification for selection of skin sensitisation endpoint:
Based on the lower molecular weight and the higher predicted dermal absorption (modeled with DERMWIN (v1.43)), which is a prerequisite for the induction of skin sensitisation, the free Guerbet alcohol was considered to be the worst case compared to the reaction product of 2-ethylhexanol with C8-16 fatty acids.
The study was furthermore conducted according to guideline (Klimisch 1).

Respiratory sensitisation

Endpoint conclusion
Additional information:
Migrated from Short description of key information:
no data available

Justification for classification or non-classification

Available data are conclusive but not sufficient for classfication of 2-hexyldecan-1-ol with regard to skin sensitisation.

There are data lacking for the classification of 2-hexyldecan-1-ol with regard to respiratory sensitisation.