Cyclohexane, 5-isocyanato-1-(isocyanatomethyl)-1,3,3-trimethyl-, homopolymer, 3,5-dimethyl-1H-pyrazole-blocked

Endpoint summary

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 adverse effect observed (not irritating)

Additional information

For the assessment of skin corrosion an in vitro study according to OECD TG 431 with reconstructed human epidermis revealed a negative result.

 

For the assessment of skin irritation an acute skin irritation/corrosion test according to OECD TG 404 was conducted on 3 rabbits receiving each 0.5 g of the unchanged test substance on the previously shorn but healthy and intact skin. Corn oil was used to moisten the test substance in order to ensure a good contact with the skin. Due to a possible irritant potential of the test substance a stepwise approach was chosen. In the first step only one animal was used and three test patches were applied to this animal. After three minutes the first patch was removed and if no skin reactions were observed, the second patch was applied and removed after one hour. If at this stage the observations indicated that with respect to animal welfare the exposure can be extended to four hours, the third patch was applied and removed after four hours and the responses were graded one hour later. The test was then completed using two additional animals, each exposed for four hours. Skin irritation was scored and recorded approx. at 1, 24, 48 and 72 hours after patch removal. If no irritation indices were observed after 72 h, the study was finished. If dermal irritation was observed, animals were monitored usually on day 7 and 14 after patch removal until the changes had completely subsided, however for not more than 14 days after application.

As result a single application of 0.5 g test substance to the skin did not cause any changes (erythema and edema scores all zero after 24, 48, and 72 hours). No relevant systemic intolerance reactions were noted.

 

A test on eye irritation/damage to the eye was conducted according to OECD TG 405 on three rabbits that were each instilled 0.1 g of the unchanged test substance into the lower lid of one eye. With respect to animal welfare a stepwise approach was chosen. In the first step only one animal was used. If one hour after treatment a severe irritation was not observed, two further rabbits were treated likewise. Eye irritation was scored and recorded approx. at 1, 24, 48 and 72 hours post application. If no irritation indices were observed after 72 hours, the study was finished. If eye irritation was observed, animals were monitored usually on day 7, 14 and 21 after application until the changes had completely subsided, however, for not more than 21 days after application.

As result a single application of 0.1 g test substance per animal into the conjunctival sac did not cause changes in cornea opacity, iris and chemosis. For conjunctiva (redness) only a slight effect was noted after 24 hours for two of three rabbits (score 1). Changes were completely subsided after 48 hours at the latest. There were no systemic intolerance reactions.

 

With respect to respiratory irritation only mild unspecific signs were observed after a 4 -hour acute inhalation exposure at the maximum technically attainable concentration of 4953 mg/m³ (see chapter Acute toxicity: inhalation). Also the data from repeated inhalation exposure does not indicate a significant respiratory irritant potential.

Justification for classification or non-classification

According to Regulation (EC) No 1272/2008, Annex I, no classification is warranted for skin irritation/corrosion or for eye irritation/damage to the eye.

 

According to Regulation (EC) No 1272/2008, Annex I, no classification is warranted for respiratory irritation.