2-Propenoic acid, 2-methyl-, C13-15-branched and linear alkyl esters

Endpoint summary

Description of key information

Skin irritation (in vitro): not irritating

Eye irritation (in vitro): not irritating

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Additional information

Skin irritation:

The potential of 2-Propenoic acid, 2-methyl-, C13-15-branched and linear alkyl esters to cause dermal irritation was assessed by a single topical application of 30 μL undiluted test substance to a reconstructed three-dimensional human epidermis model (EpiDerm™). Three EpiDerm™ tissues were incubated with the test substance for 1 hour followed by a 42-hour post-incubation period. In addition to the test substance, 30 μL per tissue of a negative control (PBS) and of a positive control (5% SDS) were applied to three tissues each. Tissue destruction was determined by measuring the metabolic activity of the tissue after exposure/post-incubation by using a colorimetric test. The reduction of mitochondrial dehydrogenase activity measured by reduced formazan production after incubation with a tetrazolium salt (MTT) was chosen as endpoint. The formazan production of the epidermal tissues treated with the test substance is compared to that of negative control tissues. The quotient of both values indicates the relative tissue viability. The test substance is not able to reduce MTT directly. Therefore, an additional MTT reduction control KC (freeze-killed control tissues) was not introduced. The relative mean viability of the tissues treated with the test substance determined after an exposure period of 1 hour with an about 42-hour post-incubation was 101.1%. The variability between the results of the tissues is within the acceptance range. The tissues treated with the positive control 5% SDS showed a relative mean viability of 2.8%, reflecting the expected sensitivity of the tissues. The mean OD570 of the negative control (PBS) fulfills the acceptance criteria and demonstrates the validity of the assay. It was concluded that 2-Propenoic acid, 2-methyl-, C13-15-branched and linear alkyl esters does not show a skin irritation potential in the EpiDerm™ in vitro skin irritation test under the test conditions chosen.

Eye irritation:

The potential of 2-Propenoic acid, 2-methyl-, C13-15-branched and linear alkyl esters to cause ocular irritation was assessed by a single topical application of 50 μL undiluted test substance to a reconstructed three-dimensional human cornea model (EpiOcular™). Two EpiOcular™ tissues were incubated with the test substance for 30 minutes followed by a 2-hour post-incubation period. In addition to the test substance, 50 μL per tissue of a negative control (deionized water) and a positive control (methyl acetate) were applied to two tissues each. Tissue destruction was determined by measuring the metabolic activity of the tissues after exposure/post-incubation by using a colorimetric test. The reduction of mitochondrial dehydrogenase activity measured by reduced formazan production after incubation with a tetrazolium salt (MTT) was chosen as endpoint. The formazan production of the epidermal tissues treated with the test substance is compared to that of negative control tissues. The ratio of the values indicates the relative tissue viability. The test substance is not able to reduce MTT directly. Therefore, an additional MTT reduction control KC (freeze-killed control tissues) was not introduced. The relative mean viability of the tissues treated with the test substance was 114.4 %. The variability between the results of the tissues is within the acceptance range. The tissues treated with the positive control methyl acetate showed a relative mean viability of 39.3 %, reflecting the expected sensitivity of the tissues. The mean OD570 of the negative control (deionized water) fulfills the acceptance criteria and demonstrates the validity of the assay. It was concluded that 2-Propenoic acid, 2-methyl-, C13-15-branched and linear alkyl esters does not show an eye irritation potential in the EpiOcular™ in vitro eye irritation test under the test conditions chosen.

Justification for classification or non-classification

Based on the results, the test item was not classified and labelled according to Regulation (EC) No 1272/2008 (CLP).

 

Nevertheless, for the group of substances (monoalkyl or monoaryl or monoalkyaryl esters of methacrylic acid) an entry in Table 3.1 and 3.2 of Annex VI of Regulation (EC) No 1272/2008 exists which has to be adopted for 2-Propenoic acid, 2-methyl-, C13-C15-branced and linear alkyl esters although obtainded data show the opposite. Thus, the substance is classified as skin irrit. cat. 2 (H315, causes skin irritation), eye irrit. cat. 2 (H319, causes serious eye irritation) and as STOT SE cat. 3 (May cause respiratory irritation) according to Regulation (EC) No 1272/2008 (CLP).