Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Administrative data

Description of key information

Key value for chemical safety assessment

Repeated dose toxicity: via oral route - systemic effects

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed
Dose descriptor:
NOAEL
840 mg/kg bw/day
Study duration:
subchronic
Species:
rat

Repeated dose toxicity: inhalation - systemic effects

Endpoint conclusion
Endpoint conclusion:
no study available

Repeated dose toxicity: inhalation - local effects

Endpoint conclusion
Endpoint conclusion:
no study available

Repeated dose toxicity: dermal - systemic effects

Endpoint conclusion
Endpoint conclusion:
no study available

Repeated dose toxicity: dermal - local effects

Endpoint conclusion
Endpoint conclusion:
no study available

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. Repeated dose toxicity studies are not available for the UVCB substance. The potential to induce hazard after repeated exposure 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

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

With regard to the Guerbet alcohols in the UVCB, a well documented 13 week subchronic toxicity study is available for 2-octyldodecan-1-ol (C20 Guerbet alcohol). Male and female rats received the sustance daily by gavage. There were no indications that 2-octyldodecan-1-ol was toxic at the limit dose of 1 ml/kg bw/d (or 840 mg/kg bw, assuming test substance density of 0.84 g/cm3).Due to their structural similarity no effects are expected after repeated oral application of 2 -hexyldecan-1-ol either.

Concerning the esters of 2 -hexyldecan-1-ol & 2-octyldodecan-1 -ol with C12 and C14 fatty acids, no study was available for the specific components as such. Taking into account toxicokinetic aspects, it can be expected that the esters are cleaved in the body to the corresponding Guerbet alcohols and fatty acids. For the Guerbet alcohols, a study with 2-octyldodecan-1-ol hasalready been discussed in this chapter. The other type of cleavage products, C12 and C14 fatty acids, is identical with nutrient fatty acids contained in the daily diet. Therefore, a toxic impact is not assumed. 

A part of the esters contained in the UVCB substance might not undergo a metabolic cleavage and could theoretically be absorbed after micellular solubilisation. Therefore, repeated dose toxicity data for esters of branched alcohols with fatty acids were also taken into account. A repeated dose toxicity study is available for the reaction product of 2-ethylhexanol with C8-16 fatty acids. This compound is a close homologue 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.

 

In a 28-day study with the close homologue, areaction product of 2-ethylhexanol with C8-16 fatty acids,a NOAEL of1000 mg/kg was found based on the lack of toxicity in clinical, neurological, hematological and biochemical examinations as well as necropsy observations, organ weights, body weights, food consumption and histopathological findings.

The UVCB substance to be registered has a low vapour pressure of <= 2.3*10-7 atm ( <= 2.3*10-2 Pa; <= 2.3*1o-4 mbar) at 20 °C) and a relatively high boiling point (>= 344 °C), indicating that inhalation as a vapour will be negligible. If the UVCB substance reaches the respiratory tract, passive diffusion is unlikely due to the high log Pow, the low water solubility the relatively high molecular weight. Theoretically, a systemic uptake could take place after micellular solubilisation. However, the oral route seems to be more appropriate for evaluating the repeated dose toxicity, as a higher bioavailability can be assumed.

Due to the expected low dermal uptake and the resulting lower bioavailability, the oral route represents a worst case compared to the dermal route. Consequently, the actual dermal LD50 can be assumed to be in the range of the oral LD50 or even higher.

In conclusion, no hazard was identified for the compounds in the UVCB substance with regard to repeated dose toxicity.

Justification for selection of repeated dose toxicity via oral route - systemic effects endpoint:
- Acceptable, well documented report.
- Study with longest study duration.
- Substance is most representative for the UVCB

Justification for classification or non-classification

Available data are conclusive but not sufficient for classfication with regard to repeated dose toxicity.