Alcohols, C7-9-iso-, C8-rich

Endpoint summary

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin

Topical application of isooctanol produced only signs of mild irritation in the rabbit following a 4 hour semi-occluded dermal patch exposure. Dermal observations were conducted 45 minutes, 24, 48 and 72 hours and 7 days after exposure. All animals survived the exposure.  Well defined erythema was noted in 1 animal at the 45 minute point while the other animals had very slight erythema. Erythema increased after the 45 minute interval. Five animals were noted with well-defined erythema at the 24 and 48 hour intervals. At the 72 hour interval, all animals were noted with well-defined erythema. Erythema increased again at the Day 7 interval; two animals were noted with severe erythema and four animals were noted with well-defined erythema. The mean skin irritation scores between 24 and 72 hours were: erythema 1.89 and edema 1.22. Skin irritation had not resolved by the end of the study period (seven days).

In vitro evaluation of skin irritation potential by the Reconstructed Human Epidermis Test Method (OECD TG 439) suggests isooctanol is irritating to skin.

 

Eye

In this study, rabbits were administered isooctanol at a dose of 0.1 ml neat solution in the eye. Observations were made at 1, 4, 24, 48, and 72 h and 4 and 7 days post instillation. Eyes were scored for irritation in accordance with the Draize Eye Test. Signs of mild irritation were observed within 1 h post instillation, but resolved to unremarkable by Day 7. There were no signs of corneal damage in any of the test animals.  Individual and mean eye irritation scores are reported in the endpoint study summary table. Four out of 6 animals had a mean cornea score of 1. These findings warrant the classification of isooctanol as an eye irritant Category 2 under EU GHS guidelines.

Effects on skin irritation/corrosion: irritating

Effects on eye irritation: slightly irritating

Justification for classification or non-classification

According to the current UN criteria (http://www.unece.org/fileadmin/DAM/trans/doc/2011/dgac10c4/ST-SG-AC10-C4-2011-2e.pdf) adopted in June 2011 (http://www.unece.org/fileadmin/DAM/trans/doc/2011/dgac10c4/ST-SG-AC10-C4-42e.pdf) should be applied (see Example 2) while interpreting classification based on pre-OECD 405 test methods. Following these guidelines classification as eye irritation category 2 applies based on corneal observations. Classification for skin irritation category 2 is based on weight of evidence. In vivo testing indicates initially moderate skin irritation that does not resolve by seven days, but without corrosion. In vitro testing suggests isooctanol is irritating to skin. Together the weight of evidence for skin irritation suggests potential for a Category 2 skin irritant.