Registration Dossier

Administrative data

Description of key information

Skin irritation (similar to OECD 404): not irritating; RA from CAS 16470-24-9
Eye irritation (similar to OECD 405): not irritating; RA from CAS 16470-24-9

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

No data is available on irritation/corrosion for the test substance. However, reliable data from irritation studies performed with CAS 16470-24-9; a close structural analogue, is available.

Skin irritation:

In a primary dermal irritation study, 3 female and 3 male New Zealand White rabbits were dermally exposed to 0.5 g of the test substance (CAS 16470-24-9; > 80% pure) diluted in polyethylen glycol and saline (50%) for 24 hours under occlusive conditions. Animals were observed for 7 days. The test substance was applied to intact and scarified skin and irritation was scored according to the Draize Scoring System after 24, 48, 72 h and 4 and 7 days. Only the findings observed with intact skin are taken in account for evaluation. Slight effects were observed in all animals. The mean score for the 24, 48 and 72 h reading for erythema was 0.8 (1.0, 1.3, 1.0, 1.0, 0.3, and 0.0, respectively) and for edema 0.4 (1.0, 0.7, 1.0, 0.0, 0.0 and 0.0, respectively). All skin reactions were fully reversible within 72 hours; in one animal erythema lasted until day 4 (fully reversible within 7 days). Animal #4 died on day 6, but this was not considered treatment-related as no symptoms had been observed before. The study was performed according to a protocol similar to the OECD test guideline 404 with major deviations: occlusive instead of semi-occlusive conditions, 24 h treatment instead of 4 h, and a 50% solution instead of a paste. Nevertheless, the data are considered reliable and suitable for assessment, as the deviations would predominantly lead to an overestimation of the effects as the conditions chosen were harsher than required by the actual guideline. However, the effects observed were below the threshold for classification and thus, the test substance is considered non-irritating and classification for skin irritation is not warranted (CIBA-GEIGY Ltd., 1981).

Supporting data from a human patch test with CAS 16470-24-9 is available. 102 females were repeatedly (11 applications) treated with the test substance (1%) and skin reactions were recorded to evaluate the irritating as well as the sensitising potential of the test substance. No effects were observed (Bayer AG, 1973).

 

Eye irritation:

An eye irritation test was performed with the undiluted test substance (CAS 16470-24-9; > 80% pure) according to a protocol similar to the OECD test guideline 405. 0.1 g of the test substance was instilled into the conjunctival sac of 3 New Zealand White rabbits per sex. The eyes of 3 animals were rinsed after 30 seconds. Scoring according to the Draize Scoring System was performed at 1, 24, 48 and 72 h and 4 and 7 days. Only the results of the non-rinsed eyes were taken into account for evaluation. The mean scores for the 24, 48 and 72 h reading for iris, cornea opacity and conjunctivae chemosis were 0 at any reading time point. The mean score for the 24, 48, and 72 h reading for conjunctivae redness was 0.2 and was fully reversible within 48 hours (score = 2 at 24 h in one animal).One animal died on day 7. The death was not considered treatment-related as no symptoms had been observed prior to death. Thus, the test substance is considered non-irritating to the eyes and classification for eye irritation is not warranted (CIBA-GEIGY Ltd., 1981).

Justification for classification or non-classification

The available data on skin and eye irritation is reliable and suitable for classification. Based on this data, classification for skin irritation/corrosion and eye irritation according to 67/584/EEC and EC/1272/2008 is not warranted.