2,2`-[6-(phenylamino)-heteromonocycle-2,4-diyl]diphenol

Endpoint summary

Description of key information

Not irritating to skin.
Not irritating to eyes.

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:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin irritation
The primary skin irritation potential of the test item was investigated according to OECD test Guideline No. 404. The test item was applied by topical semi-occlusive application of 0.5 g to the intact left flank of each of three young adult New Zealand White rabbits. The duration of treatment was four hours. The scoring of skin reactions was performed 1, 24, 48 and 72 hours after removal of the dressing.
The mean score was calculated across 3 scoring times (24, 48 and 72 hours after patch removal) for each animal for erythema/eschar grades and for oedema grades, separately. The mean erythema/eschar score of the three animals was 0.33, 0.00 and 0.33, respectively and the mean oedema score was 0.00 for all animals.

The application of the test item to the skin resulted in very slight erythema which was reversible and no longer evident 48 hours after treatment. The test item caused no staining of the treated skin. No corrosive effects were noted on the treated skin of any animal at any of the measuring intervals and no clinical signs were observed.

Thus, the test item did not induce significant or irreversible damage to the skin.

 

Eye irritation

The eye irritation potential of the test item was investigated according to OECD Guideline No. 405. The test item was applied by instillation of 0.1 g into the left eye of each of three young adult New Zealand White rabbits. Scoring of irritation effects was performed approximately 1, 24, 48 and 72 hours, as well as 7 and 10 days after test item instillation. 
The mean score was calculated across 3 scoring times (24, 48 and 72 hours after instillation) for each animal for corneal opacity, iris, redness and chemosis of the conjuctivae, separately. The individual mean scores for corneal opacity and iris were 0.00 for all three animals. The individual mean scores for the conjuctivae were 0.33, 1.33 and 1.00 for reddening and 0.00, 0.33 and 0.33 for chemosis, respectively. 

The instillation of test item into the eye resulted in mild, early-onset and transient ocular changes, such as reddening of the conjuctivae and sclerae, discharge and chemosis. These effects were reversible and were no longer evident 10 days after treatment, the end of observation period for all animals.
No abnormal findings were observed in the cornea or iris of any animal at any of the examinations. No corrosion was observed at any of the measuring intervals. No staining of the treated eyes by the test item was observed, although test item remnants were visible in the conjuctival sac 1 hour (all animals) and 24 hours (one animal) post treatment. No clinical signs were observed.

Thus, the test item did not induce significant or irreversible damage to the rabbit eye.

 

Justification for classification or non-classification

Skin irritation

According to the CLP Regulation (EC 1272/2008), classification as skin irritant (category 2) applies if the substance produces:
- mean value of ≥ 2.3 - ≤ 4.0 for erythema/eschar or for oedema in at least 2 of 3 tested animals from gradings at 24, 48 and 72 hours after patch removal or, if reactions are delayed, from grades on 3 consecutive days after the onset of skin reactions; or
- inflammation that persists to the end of the observation period normally 14 days in at least 2 animals, particularly taking into account alopecia (limited area), hyperkeratosis, hyperplasia, and scaling; or
- in some cases where there is pronounced variability of response among animals, with very definite positive effects related to chemical exposure in a single animal but less than the criteria above.
In the available study, no signs of irritation were seen, thus test item is not classified as a skin irritant.

 

Eye irritation
According to the CLP Regulation (EC 1272/2008), classification as eye irritant (category 2) applies if the substance produces in at least 2/3 tested animals, a positive response of:
- corneal opacity ≥ 1 and/or iritis ≥ 1, and/or
- conjunctival redness ≥ 2 and/or
- conjunctival oedema (chemosis) ≥ 2
calculated as the mean scores following grading at 24, 48 and 72 hours after installation of the test material, and which fully reverses within an observation period of 21 days.
Based on experimental findings in the key study, scores for effects observed are below the reference thresholds in at least 2/3 animals.

In conclusion, the test item is not classified for the eye/skin irritation, according to the CLP Regulation (EC) No. 1272/2008.