5-amino-3-[[4-[[4-[[4-anilino-2-hydroxyphenyl]azo]phenyl]amino]-3-sulphophenyl]azo]-4-hydroxynaphthalene-2,7-disulphonic acid, sodium salt

Endpoint summary

Description of key information

Not skin irritating

Eye irrit, 2 (H319), according to the CLP regulation (EC) 1272/2008

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:

adverse effect observed (irritating)

Additional information

The following data was obtained for the Similar Substance 01. It is expected that the Target substance will present similar potential for skin and eye irritation/corrosion. Justification for the use of a read-across approach is provided in Section 13 of IUCLID.

SKIN IRRITATION

The irritancy potential of the Similar Substance 01 to the skin of New Zealand white rabbit was assessed according to the OECD Guideline 404. The intact skin of the rabbits was exposed for 4 hours to the substance (0.5 g moistened with bi-distilled water), in a semi-occlusive dressing. No acute clinical symptoms were observed and no mortality occurred. A black coloration on the back was observed in all animals from 1 to 72 hours, but no signs of irritations were observed. Test item showed a primary irritation score of 0.00 when applied to intact rabbit skin. Local signs (mean values from 1 hour to 72 hours) consisted of grade 0.00 erythema and grade 0.00 edema.

The study outcomes are confirmed by the results of a second experiment, during which three rabbits were treated with the substance (0.5 g, unchanged). The study was conducted according to the OECD guideline 404. 30 minutes after the patches were removed, very slight erythema (grade 1) was observed in two of the animals. In the readings carried out 24, 48 and 72 hours after administration, no alterations were observed on the skin of any of the animals. Mean scores for erythema and edema, 24 , 48 and 72 hours after treatment were 0.00 for the three animals. Following the last reading, the study was ended.

EYE IRRITATION

The irritancy potential of the Similar Substance 01 to the eye of New Zealand white rabbit was assessed, according to the OECD Guideline 405. Black staining of the cornea, iris, conjunctivae, nictitating membrane, sclera and of the eyelashes by the test material was noted in all animals until termination of observation. No iridal or cornea irritation effects were observed. Erythema was not visible in any of the animals through the study. Conjunctivae discharge and chemosis was observed in all animals after 1 hour and persisted after 24 hours for two out of three animals. No corrosion and no mortality occurred.

A second experiment was conducted under similar conditions, according to the OECD guideline 405. The right eye of three male rabbits was treated with the substance (non diluted) and after 24 hours the eyes were washed. In the course of the first 24 hours after administration, the substance induced edematic lesions. Also observed were injected vessels in the bulbar conjunctivae of all animals and discharge ranging from mild to moistening of the lids and surrounding hair, affecting a considerable area around the eye. All the animals showed opacity of the cornea. Due to the colouring produced by the test substance in the palpebral conjunctivae and iris of some of the animals, diffused crimson vessels were observed in only one animal. 2, 3 and 4 days following administration, observed ocular injuries had begun to subside. In the reading carried out 7 days post-administration, one animal showed vessels clearly more injected than normal in the palpebral conjunctivae. Also, another animal showed nearly half closed, swollen lids and opacity of the cornea which occupied less than one quarter of the total area.

In a third experiment, the substance was assessed according to the OECD guideline 405. The observations of the effects in cornea, iris and conjunctivae erythema at 1, 24 and 48 hours was not possible due to the black staining produced by the substance; at 72 hours and 7 days the staining only affected the nictitante membrane. Formation of reversible conjuctivae chemosis was noted in all animals. The mean conjunctivae chemosis score was greater than 2 in all animals. Effects on the cornea, iris or conjunctiva resulted to be fully recovered within the 21st day; only staining of the nictitante membrane persisted until the reading at 21st day.

The differences between the conclusion reached in the first test respect those trace in the other two experiments may be attribute to a different approach about how to consider the staining. In fact, although black staining of the cornea, iris, conjunctivae, nictitating membrane, sclera and of the eyelashes by the test material was noted in all animals until termination of observation (i.e. 72 hours), it was concluded that the substance was not irritating.

Based on the information given in the other two experiments, the substance seems to be able to cause eye irritation. All the effects on the cornea, iris or conjunctiva resulted to be fully recovered within the 21st day; only staining of the nictitante membrane persisted until the reading at 21^st day. However, considering that humans have only a rudimentary nictitante membrane, a classification as Eye Irrit 2 (H319) seems to be appropriate.

Justification for classification or non-classification

According to the CLP Regulation (EC) No 1272/2008, 3.2 Skin corrosion/irritation section, skin irritation means the production of reversible damage to the skin following the application of a test substance for up to 4 hours.

In the key study, the mean values from grading at 24, 48 and 72 hours after patch removal were lower than 2.3 in all animals for both erythema/eschar and oedema reactions.

According to the CLP Regulation (EC) No 1272/2008, serious eye damage means the production of tissue damage in the eye, or serious physical decay of vision, following application of a test substance, which is not fully reversible within 21 days of application.

Based on the review of all the experiments available, the substance seems to be able to cause eye irritation; however, effects can be recovered within 21 days.

In conclusion, the substance does not meet the criteria to be classified for the skin irritation; however, it should be classified as eye irritating, category 2 (H319), according to the CLP Regulation (EC) No 1272/2008.