Registration Dossier

Administrative data

Description of key information

No significant skin sensitising potential in guinea pig maximisation test.

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not sensitising)
Additional information:

No information was available on the substance itself, thus the assessment relied on a read across approach. Solvent Red 008 and Similar Substance 02 are chromium complexes with 2 ligands. In both cases, the 2 ligands have the same chemical structure, i.e. a phenyl ring connected via diazo bond to a phenyl pyrazole. These ligands show minor differences in the position of substituents, i.e. hydroxy and nitro groups, as well as in the presence of a sulfonate group in Similar Substance 02.

All information about the read across process is inserted in section 13.

Guinea pig maximization study was conducted to evaluate the skin sensitising potential of Similar Substance 02 according to OECD guideline 406 and EU method B.6. Based on the results of a preliminary study, 5 and 50 % were selected as intradermal and topical induction doses respectively. The highest non-irritating test substance concentration used for challenge application was 50 %. 

The first challenge with test substance at 50 % gave 60 % positive skin reactions in the control group and 55 % in the test group. Thus, a second challenge was performed with an additional control group. Overall, test substance at 50 % in vaselinum album was determined twice as the highest non-irritating concentration.

However, by comparison, the second challenge did not confirm the first challenge. Indeed, no positive reactions were noted with test article at 50 % in the control group, while 15 % positive reactions were noted in the test group. On these bases, the interpretation is very ambiguous. Further, an additional test substance concentration of 25 % was applied in the second challenge procedure, causing no skin reactions in the control and test group.


Under the conditions of the study, the test substance was not considered to induce delayed contact hypersensitivity in treated animals when tested at the concentration of 25 %.

No toxic symptoms were noted in control and test animals.

Respiratory sensitisation

Endpoint conclusion
Endpoint conclusion:
no study available

Justification for classification or non-classification

According to the CLP Regulation (EC 1272/2008), skin sensitizer is a substance that will lead to an allergic response following skin contact. In case of a guinea pig maximisation test, a response of at least 30 % of the animals is considered as positive.

Under the experimental conditions employed, 0 % of the animals of the test and control groups showed skin reactions 24 and 48 hours upon challenge with test substance at 25 % concentration, thus no classification applied.

Based on the read across approach, Solvent Red 008 was considered as non skin sensitising.