Reaction mass of disodium 3-[(5-chloro-2-phenoxyphenyl)azo]-4-hydroxy-5-[[(p-tolyl)sulphonyl]amino]naphthalene-2,7-disulphonate and 3-[(5-chloro-2-phenoxyphenyl)azo]-4-hydroxy-5-[[(ptolyl)sulphonyl]amino]naphthalene-2,7-disulphonic acid

Endpoint summary

Description of key information

not-sensitising

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

The determination of the sensitizing potential has been based on the Read Across approach:

Acid Red 249:1 is a multiconstituent substance composed by the acidic and the sodium salt forms of the same structure (72.7 % and 14.95 % of the substances respectively).

The tests was performed on the similar substance 01 which is major component of the multiconstituent substance. Considering the high similarity between the structures and the composition of the substance the Read Across approach is considered as acceptable. See section 13.

The sensitizing potential was determined by a Maximixation test, according to OECD 406 guideline and GLP. The reaction on the test substance was observed in Guinea Pigs for 48 hours. Induction reactions, challenge reactions and changes in body weight were observed. Under the experimental conditions employed, 10% and 15% of the animals of the test group showed skin reactions 24 and 48 hours after removing the dressings, respectively. The substance does not show any sensitizing potential under the test condition.

Based on the test conducted on Similar Substance 01, even the Acid Red 249:1 is expected to be not sensitizer.

Justification for selection of skin sensitisation endpoint:

The test was performed on the major component of the multiconstituent substance

Respiratory sensitisation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information:

No data available

Justification for classification or non-classification

Skin sensitisation

According to the guide to the labelling of dangerous substances and the criteria for the choice of sentences indicating particular hazards (R sentences) attributed to dangerous substances (Commission Directive 93/21/EEC, April 27, 1993) a test article was classified as a sensitizer in the case where a positive response was noted in at least 30 % of the animals.

Under the experimental conditions employed, 10% and 15% of the animals of the test group showed skin reactions 24 and 48 hours after removing the dressings, respectively, therefore it cannot be classified a sensitizer (contact allergenic) potential in albino guinea pigs.

However, according to the CLP Regulation n. 1272/2008, a substances shall be classified as skin sensitisers (Category 1) where data are not sufficient for sub- categorisation (1A and 1B) in accordance with the following criteria:

(a) if there is evidence in humans that the substance can lead to sensitisation by skin contact in a substantial number of persons; or

(b) if there are positive results from an appropriate animal test ( according to 3.4.2.2.4.1).

At this point, when an adjuvant type guinea pig test method for skin sensitisation is used, a response of at least 30 % of the animals is considered as positive. For a non-adjuvant guinea pig test method a response of at least 15 % of the animals is considered positive.

The study reported was performed according to OECD 406, that includes the use of the adjuvant.

Positive results were observed, 10% and 15% of the animals of the test group showed skin reactions 24 and 48 hours after removing the dressings, respectively).

Based on these results, according to the paragraph 3.4. of the CLP Regulation n. 1272/2008, the substance shall be non classified as a skin sensitizer.

Respiratory sensitisation

No study available for this endpoint.