Dimethyl cyclohexane-1,4-dicarboxylate

Endpoint summary

Additional information

Dermal irritation

The test substance, dimethyl 1,4-cyclohexanedicarboxylate (DMCD), was applied to the clipped back of 2 guinea pigs at concentrations of 5 and 10 mL/kg. Subsequently, the application site was occluded with a woven pad and a rubber dental dam for 24 hours. Following the application period, very slight edema was noted at the edge of the application site, which was accompanied by no or slight redness. Under the conditions of this study, DMCD was determined to be a very slight skin irritant.

Ocular irritation

To determine the potential for dimethyl 1,4-cyclohexanedicarboxylate (DMCD) to produce ocular irritation, data from a related compound, 1,4 - cyclohexane dicarboxylic acid (CHDA) was evaluated. CHDA was instilled into both eyes of 3 rabbits, and for each rabbit, the test article was removed from one eye by washing. Each eye was evaluated for evidence of irritation at 1, 24, and 48 hours after instillation, and after 7 and 10 days. In the unwashed eyes, moderate irritation was observed in 3 of 3 eyes at 1 and 24 hours after instillation, and slight irritation was observed in 3 of 3 eyes at 48 hours after instillation. Irritation was accompanied by moderate corneal opacity at 24 and 48 hours after instillation and by slight corneal opacity after 7 days. By 10 days after test article instillation, 3 of 3 eyes appeared normal. In the washed eyes, slight irritation was observed in 3 of 3 eyes at 1, 24, and 48 hours after instillation, and by 7 days after test article instillation, 3 of 3 eyes appeared normal.

Justification for classification or non-classification

Based on an absence of corrosivity and limited irritant effects observed when the neat test material or the test material in 25- 40% ethanol, 3A alcohol, or acetone:corn oil was applied under occluded contact to guinea pig skin for 24 hours, 2,2,4-trimethyl-1,3-pentanediol is not considered to be a primary skin irritant. 2,2,4-Trimethyl-1,3-pentanediol is not classified for Skin Irritation/Corrosion according to Annex I of Directive 67/548/EEC. Based on limited signs of irritation in the dermal toxicity studies, 2,2,4-trimethyl-1,3-pentanediol is not classified for Skin Irritation/ Corrosion according to EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008 or UN Globally Harmonized System of Classification and Labelling of Chemicals (GHS).

In a non-guideline study, reversible irritation was observed when a related compound (CHDA) was instilled into the conjunctival sac of 3 New Zealand white rabbits. Consequently, DMCD, a compound which produces CHDA in vivo through demethylation, is not currently classified for Serious Eye Damage/ Eye Irritation according to Annex I of Directive 67/548/EEC, and also is not classified for Serious Eye Damage/ Eye Irritation (Category 2) according to EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008 or Category 2 or 2B for Serious Eye Damage/ Eye Irritation according to UN Globally Harmonized System of Classification and Labelling of Chemicals (GHS).