Benzoic acid, 2-[4-(diethylamino)-2-hydroxybenzoyl]-, hexyl ester

Endpoint summary

Description of key information

Skin irritation (OECD TG 404, GLP): not irritating
Eye irritation (OECD TG 405, GLP): not irritating

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)

Additional information

Skin irritation:

Two skin irritation studies according OECD TG 404 and GLP were conducted with two specifications of Hexyl 2-(1-(diethylaminohydroxyphenyl)methanoyl)benzoate:

The key study (BASFAG18H0636/022173) used the test substance as pasty melt, representing the currently manufactured product.

Additional study (BASFAG18H0408/992237) used the test substance in cristalline form.

In both studies 3 young adult New Zealand white rabbits (males and females) were exposed to 5 mL and 5 g (moistened with aqua bidest) of the test substance in the key study and in the supporting study respectively. Hexyl 2-(1-(diethylaminohydroxyphenyl)methanoyl)benzoate was applied on a patch of 2.5 cm x 2.5 cm in a semiocclusive dressing for 4 hours. After the 4 hours exposure time, the test substance was washed of and the animals were observed for 7 days after removal of the patch in the key study.

Irritation was scored according to the EU method B.5 and the OECD 405 guideline. The average irritation scores (including all relevant observation timepoints and animals tested) were as follows:

- key study: 1.3 for erythema and 0.0 for edema

- additional study: 0.1 for erythema and 0.0 for edema.

The cutaneous reactions observed in the key study (reversible within 7 days), were based on a secondary effect, beeing related to a prolonged exposure period due to residuals/ adhesive remains of the test substance which were still found after subsequent washing at the time points when the skin reactions were assessed (1, 24, 48, 72 hours and 7 days). The other study results support this assumption since no remains of test substance were found, leading to lower erythema scores.

In line, repeated dermal application of Hexyl 2-(1-(diethylaminohydroxyphenyl)methanoyl)benzoate (20 or 10%) on guinea pigs showed no more severe skin reactions than observed after application of the respective vehicle (BASFAG99H0636/02074).

Taken together, the average erythema scores (< 2) in addition to the edema scores in both studies (0) provide evidence for the absence of a signficant dermal irritation potential of Hexyl 2-(1-(diethylaminohydroxyphenyl)methanoyl)benzoate.

Eye irritation:

Two eye irritation studies according to OECD 405 and GLP were conducted with Hexyl 2-(1-(diethylaminohydroxyphenyl)methanoyl)benzoate.

BASFAG11H0636/022174 was selected as the key study because the used test substance specification, i.e. pasty melt, represents the currently manufactured product.

In the additional study (BASFAG11H0408/992236) the crystalline form of Hexyl 2-(1-(diethylaminohydroxyphenyl)methanoyl)benzoate was applied directly to the eye.

Both studies showed comparable results:

In the key study, the test substance (melted for volume determination, i.e. 0.1 mL and subsequent cooling down) was instilled into the conjunctival sac of the right eye of young adult New Zealand White rabbits (2 males, 1 female) for 24 hours. The substance was rinsed with water after 24 hours. Animals then were observed for 72 hours. Irritation was scored by EU Method B.5 and OECD Method 405. The average score (including all relevant observation timepoints and animals tested) for eye irritation was as follows:

- key study: 0.0 for corneal opacity and for iris, 0.1 for conjunctival redness and 0.0 for chemosis

- additional study: 0.0 for corneal opacity and for iris, 0.3 for conjunctival redness and 0.0 for chemosis

Taken together, the present data provide evidence for the absence of a significant eye irritation potential of Hexyl 2-(1-(diethylaminohydroxyphenyl)methanoyl)benzoate.

Justification for classification or non-classification

The present data on skin and eye irritation do not fulfill the criteria laid down in 67/548/EEC and 1272/2008/EEC, and therefore, a non-classification is warranted.