disodium [N, 2-[(2-hydroxy-5-nitrophenyl)azo]-3-oxobutyramidato(2-)][3-hydroxy-4-[(2-hydroxy-1-naphthyl)azo]-7-nitronaphthalene-1-sulphonato(3-)]chromate(2-)

Endpoint summary

Description of key information

Skin sensitising

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (sensitising)

Additional information:

No studies on "Skin Sensitisation" are available for the substance in itself nevertheless, studies were conducted with an analogue molecule (Similar Substance 01). Further information are reported in the Read Across justification attached to section 13.

The potential of the test material to provoke delayed skin sensitization reactions was tested in a study conducted following the maximisation test described in the OECD guideline 406, EU method B.6 (Skin sensitisation).

The test was performed on 5 male and 5 female guinea pigs in the test group and 5 male guinea pigs in the control group.

Test article was first tested by intradermal injection in a pretest phase at 5 % in physiological saline; then several epidermal applications where performed using different concentrations of the substance on separate animals: 5, 10, 20, 30, 40 and 50 % in physiological saline were tested. 50 % was the highest possible concentration of the test article in physiological saline. The tested concentrations did not induce erythema reactions.

5 % and 50 % were the concentrations selected for the intradermal application and epidermal application respectively. After the first challenge application, reaction were observed in 40 % of the animals of the control group, therefore a second challenge, using a lower test article concentration and a new control group, was performed. 10 % was the new concentration of test article tested. After the second challenge test none of the control group animals showed skin reactions 24 and 48 hours after removing the dressing. In the test group 50 % and 70 % of the animals showed skin reactions after 24 and 48 hours after removing the dressing, respectively.

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

According to CLP Regulation (EC 1272/2008), a substance has to be classified as Skin sensitiser Sub-category 1B if during a Guinea pig maximisation test the animals with a positive response are:

≥ 30 % to < 60 % responding at > 0,1 % to ≤ 1 % intradermal induction dose or

≥ 30 % responding at > 1 % intradermal induction dose

During the test more than 30 % of the animals showed a reaction, therefore the test substance is Classified as skin sensitizing Sub-category 1B according to the CLP Regulation (EC 1272/2008).