Methyl 2-ethylhexanoate

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

The study was performed according to US EPA OPPTS 870.2600 and OECD 406 to assess the skin sensitisation potential of the test substance in accordance with GLP. The study was conducted using a preliminary irritation screen, a two-stage induction phase and a challenge phase. Preliminary irritation testing was performed on eight animals to establish the highest concentration of the test substance that causes mild to moderate irritation for use in the induction phases of the study and the highest non-irritating concentration (HNIC) of the test substance for use in the challenge phase of the study. The concentration of the test substance selected for the intradermal phase of the study was 5% w/w mixture in mineral oil. The undiluted test substance with the use of sodium lauryl sulfate was determined to be the concentration for the topical induction phase, and a 50% w/w mixture in mineral oil was selected as the HNIC for the challenge phase of the study. The first stage of the induction phase involved intradermal injections of a 5% w/w mixture of the test substance in mineral oil, a 5% w/w mixture of the test substance in 50% v/v Complete Freund's Adjuvant in distilled water, and 50% aqueous Complete Freund's Adjuvant alone into the dorsal area of each of 10 guinea pigs. A sham group ( 5 animals) was maintained under the same environmental conditions and injected with mineral oil ( 100% ), mineral oil mixed with 50% v/v Complete Freund's Adjuvant in distilled water, and 50% aqueous Complete Freund's Adjuvant alone into the dorsal area. The second stage of the induction phase entailed the topical application of the undiluted test substance onto the shaved dorsal area of the test group animals. Due to a lack of irritation produced during preliminary testing all animals received a pretreatment of sodium lauryl sulfate prior to test substance application. The sham group was treated with mineral oil for topical induction. Twenty days after test initiation, a challenge dose of the test substance (50% w /w mixture in mineral oil) was applied to a naive site on each test animal. The sham group was also treated with a 50% w/w mixture of the test substance in mineral oil for challenge. Approximately one hour after the topical induction patch removal and 24 and 48 hours after the challenge phase patch removal, the animals were evaluated for the presence of erythema. Under the conditions of this study, the test material is not considered to be a contact skin sensitizer.

Migrated from Short description of key information:
non-sensitising, Guinea Pig (male), EPA OPPTS 870.2600, Product Safety Laboratories 2003

Justification for selection of skin sensitisation endpoint:
one in vivo study Klimisch 1 according to GLP and following Magnusson-Kligman GPMT Method methodology.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

The substance does not meet classification criteria under EU Directive 67/548/EEC for skin sensitisation.

The substance does not meet classification criteria under Regulation (EC) No 1272/2008 for skin sensitisation.

In the GPMT test the severity of effects were limited and in the range of the naive control group (erythema score 0.5). The effects were specifically less than erythema score 1 in all organisms. The test was validated by a historic positive control group which gave responses of score 1 to 3 at > 1% intradermal induction dose. Under EU criteria no significant effects were observed in the in vivo GPMT study on exposure to the substance at > 5% v/v intradermal induction dose. The substance cannot be considered a skin sensitiser.