Fatty acids, C12-18 (even-numbered), 3-methylbutyl esters

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

Justification for read-across

There are no data on the skin sensitisation potential of Fatty acids, C12-18, even numbered, 3-methylbutyl esters (CAS 1314963-50-2). The assessment was therefore based on studies conducted with analogue (source) substances as part of a read across approach, which is in accordance with Regulation (EC) No. 1907/2006, Annex XI, 1.5. For each specific endpoint the source substance(s) structurally closest to the target substance is/are chosen for read-across, with due regard to the requirements of adequacy and reliability of the available data. Structural similarities and similarities in properties and/or activities of the source and target substance are the basis of read-across. A detailed justification for the analogue read-across approach is provided in the technical dossier (see IUCLID Section 13).

CAS 163961-32-8

Fatty acids, C16-18 and C18-unsatd., branched and linear, butyl esters (CAS 163961-32-8) was tested in a guinea pig maximisation test according to OECD guideline 406 (Sanders, 2002a). Reliability checks had been performed 2 times a year with 10 test and 5 control animals using alpha-hexylcinnamaldehyde and 2-Mercaptobenzothiazole as positive control substances confirming the sensitivity and validity of the test method. 20 test and 10 control animals (Dunkin-Hartley guinea pigs) were induced intradermally with 1% test substance (no data on purity) in arachis oil BP. The epidermal induction was performed with the undiluted test substance. The animals were challenged with 50% (10 test and 5 control animals) and 75% (10 test and 5 control animals) test substance solutions in arachis oil. 24 and 48 hours after termination of the challenge exposure, skin readings revealed a positive reaction in only 1/10 animals, therefore the test substance was concluded to be not a skin sensitiser.

CAS 110-27-0

A guinea pig maximisation test was performed with Isopropyl myristate (CAS 110-27-0) according to a protocol similar to the OECD guideline 406 (Potokar, 1984). No range-finding study was performed for dose selection. 15 female Pirbright-Hartley guinea pigs were treated with the test substance at 5% for intra- and epidermal induction on days 1 and 7, respectively. 20 animals served as negative controls (one control animal died during the study). A positive control group was not included in the study and no information, on if, periodical testing of strain sensitivity occurred. 14 days after the epidermal induction, epidermal challenging was performed with a 25% test material dilution in 2% Carboxymethylcellulose and 0.5% Cremophor. 48 and 72 hours after challenging skin examination revealed no irritation in the test group or in the control group. Thus, the test material was found to be not sensitising to the skin of guinea pigs, when used as 5% solution for induction and 25% solution for challenge.

CAS 34316-64-8

A guinea pig maximisation test was performed with Hexyl laurate (CAS 34316-64-8) according to a protocol similar to OECD guideline 406 (Gloxhuber, 1978). Only a short summary is available, therefore detailed information is lacking. 20 female Pirbright-Hartley guinea pigs were induced with the test material (no data on purity). The route of induction procedure and the induction concentration was not specified. The challenge was performed epicutaneously with 1% test material in Vaseline for 24 h. A negative control group of 10 animals was included. No individual data given. However, the experimental and control animals reacted in a similar manner to the retreatment with perceivable reddening of the parts of the skin treated; this quickly subsided and 24 hours after removal of the patch no further reaction was visible. Thus, based on the results of this study, no sensitisation potential of the test substance was indicated.

Conclusion

A read-across approach was applied to assess the skin sensitising potential of the target substance Fatty acids, C12-18, even numbered, 3-methylbutyl esters (CAS 1314963-50-2). Guinea pig maximisation studies performed with the source substances Fatty acids, C16-18 and C18-unsatd., branched and linear, butyl esters (CAS 163961-32-8), Isopropyl myristate (CAS 110-27-0) and Hexyl laurate (CAS 34316-64-8) were negative. Taking into account the available information, Fatty acids, C12-18, even numbered, 3-methylbutyl esters is considered to be not skin sensitising.

Migrated from Short description of key information:
Skin sensitisation (GPMT): not sensitising

Justification for selection of skin sensitisation endpoint:
Hazard assessment is conducted by means of read-across from structural analogues. All available studies are adequate and reliable based on the identified similarities in structure and intrinsic properties between the source and target substances and overall quality assessment (refer to the endpoint discussion for further details).

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information:

Justification for selection of respiratory sensitisation endpoint:
Study not required according to Annex VII-X of Regulation (EC) No 1907/2006.

Justification for classification or non-classification

According to Article 13 of Regulation (EC) No. 1907/2006 "General Requirements for Generation of Information on Intrinsic Properties of substances", information on intrinsic properties of substances may be generated by means other than tests e.g. from information from structurally related substances (grouping or read-across), provided that conditions set out in Annex XI are met. Annex XI, "General rules for adaptation of this standard testing regime set out in Annexes VII to X” states that “substances whose physicochemical, toxicological and ecotoxicological properties are likely to be similar or follow a regular pattern as a result of structural similarity may be considered as a group, or ‘category’ of substances. This avoids the need to test every substance for every endpoint". Since the analogue concept is applied to Fatty acids, C12-18, even numbered, 3-methylbutyl esters (CAS 1314963-50-2), data will be generated from data for reference source substance(s) to avoid unnecessary animal testing. Additionally, once the analogue read-across concept is applied, substances will be classified and labelled on this basis. Therefore, based on the analogue read-across approach, the available data on skin sensitisation do not meet the classification criteria according to Regulation (EC) 1272/2008 or Directive 67/548/EEC, and are therefore conclusive but not sufficient for classification.