N,N-dimethylacrylamide

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

N,N-dimethylacrylamide was tested for its skin sensitising properties in the guinea pig maximization test based on the method of Magnusson and Kligman (Product Safety Laboratories, 2003), comparable to OECD guideline 406. Ten female animals were induced intradermally with 6 injections (2 injections each of 0.1 ml 50% v/v Freund's adjuvant; 2 injections each of 0.1 ml of the test substance formulation (5% w/w solution) and 2 injections each of 0.1 ml 5% v/v Freund's adjuvant with the test substance (5% w/w solution)) and one week later epicutaneously with 25% solution of the test substance for 48 hours. Twenty-one days after intradermal induction animals were challenged epicutaneously with 25% solution of the test substance for 24 hours. The skin reactions were scored 24 and 48 hours later. One naive control group was used, which was given the same injections (A, B C) but without test substance, only with the formulating agent. Alpha-hexylcinnamaldehyde was used as a positive control. After the challenge (24 hours after removal of the patch) with the 25% test substance preparation, very faint erythema (0.5) was noted at five of ten test sites 24 hours following the challenge application. Similar irritation persisted at two sites through 48 hours. In the control group, very faint erythema (0.5) was noted at one of five test sites 24 hours following the challenge application. All animals were free of irritation by 48 hours. In the test with the positive control alpha-hexylcinnamaldehyde, 6 out of 10 test animals showed faint to moderate erythema (1-2) 24 and 48 hours after challenge patch removal. Very faint erythema (0.5) was noted for three other sites at the 24 and 48 hour interval.

According to the evaluation criteria as outlined in the study report, erythema scores of 0.5 or less are not considered to be positive responses. Therefore, based on the results of the study N,N-dimethylacrylamide was considered to be not sensitising to the skin.

Migrated from Short description of key information:
N,N-dimethylacrylamide is not considered to be a skin sensitiser.

Justification for classification or non-classification

Based on the result of the skin sensitisation test, the substance does not need to be classified according to Directive 67/548/EEC and according to the EU Classification, Labelling and Packaging of Substances and Mixtures (CLP) Regulation (EC) No. 1272/2008.