5-amino-o-cresol

Endpoint summary

Description of key information

Eye irritation

According to the result of the key studies (Klimisch 1, GLP compliant, OECD guidelines 438 and 492 methods), the registered substance was defined as No Classififed for Eye Irritation/Corrosion according to CLP regulation.

Skin irritation:

According to the results of the key studies (GLP compliant, Klimisch 1, OECD guideline method 439 and 431), the registered subtance 4 -amino-2 -hydroxytoluene did not induce skin irritation or corrosion on reconstructed human epidermis and was Not classiffied for Irritation and Corrosion.

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

Two available key studies were performed in order to assess the eye irritation potential of the registered substance.

- An Isolated Chicken Eye Test (ICE) was performed following OECD GLP principle, OECD guideline 438 method and was quoted as Klimisch 1 :

4 -amino-2 -hydroxytoluene was evaluated neat for eye irritation potential in the Isolated Chicken Eye (ICE) test. In addition, the test included a negative control (saline) and a positive control (BAC). Chicken eyes were obtained from slaughter animals used for human consumption. The isolated chicken eyes were exposed to a single application of 30 mg for 10 seconds followed by a 20 mL saline rinse. 4 -amino-2-Hydroxytoluene did not cause corneal effects other than very slight corneal swelling (mean swelling 1%).  Microscopic examination of the corneas did not reveal any abnormalities.

-A Human Cornea Model Test was performed following OECD 492 method and GLP principle and was quoted as Klimisch 1 :

Each 50 mg of the test item, were applied to each of duplicate EpiOcularTM tissues for 6 hours. Each 50 µL of the negative control (deionised water) and of the positive control (methyl acetate) were also applied to duplicate tissues each. Viability quantification was performed on cells using MTT reduction to formazan approach after 6 hours exposure period and 18 hours post exposure period. Irritating effects were not observed following incubation with 4-Amino-2-Hydroxytoluene (A027). Compared with the negative control the corrected relative mean absorption value corresponding to the viability of the tissues did not decrease below 60% (71.5%).4-amino-2 -hydroxytoluene (A027) was not classified as irritating for eye according CLP regulation.

One in vitro studies was available to assess the potential corrosion of the test item :

- A Skin Corrosion potential test using EpiSkinTM Reconstructed Human Epidermis model was performed (GLP compliant, OECD 431 method, Klimisch 1). Duplicate tissues were treated with the test item for exposure periods of 3 and 60 minutes. Negative and positive control groups were treated for each exposure period. At the end of the exposure period the test item was rinsed from each tissue before each tissue was taken for MTT-loading. The optical density (OD) was measured at 562 nm. Under experimental conditions of the study, the registered substance did not induce decrease of the viability, 100.9% of viability after 3 minutes exposure and 98.4.8% of viability after 60 minutes exposure.

Justification for classification or non-classification

Eye irritation

According the results of the key studies (Klimisch 1, GLP compliant, OECD guideline 438 method and 492 method), the registered substance was defined as No Classififed for Eye Irritation/Corrosion Potential according to CLP regulation.

Skin irritation:

According to the results of the key studies (GLP compliant, Klimisch 1, OECD guideline method 439 and 431), the registered subtance 4 -amino-2 -hydroxytoluene did not induce skin irritation or corrosion on reconstructed human epidermis and was Not classiffied for Irritation and Corrosion according CLP criteria.