4-phenylbutan-2-one

Endpoint summary

Description of key information

The substance is not irritating to the skin or the eyes.

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

Skin irritation / corrosion

Key study
4-phenylbutan-2-one is considered to be not irritating to skin. The result from a GLP study in rabbits conducted similar to OECD TG 404 was considered reliable with restrictions and showed slight skin reactions in 3 out of 4 animals that were reversible within 7 days. Only one animal showed a very slight erythema (grade 0.5) until day 7 of the study (Haynes 1988). Since this is a very slight erythema it might be assumed that the reaction would be fully reversible within 14 days.

In conclusion, this study showed that the test item caused slight, reversible skin irritation, not fulfilling a threshold for classification.

Supporting information
In the skin irritation study in rabbits from Bagley (1996) only slight, reversible skin irritation is reported, supporting the non-classification of 4 -phenylbutan-2-one.

Additionally, in two further in vitro studies with human skin it was concluded that the test substance is not corrosive skin in vitro (Fentem 1998, Kandarova 2006).

In a guideline-conform in vitro study with EpiSkin a relative absorbance of 46.0 % was reported and indicated a skin irritating potential of 4 -penylbutan-2-one (threshold for irritancy: ≤50%) (Heppenheimer 2012). However, the measured value was very close to the irritation threshold. Taking into account the negative results of the in vivo data, it is concluded that this in vitro test might be assumed to be false positive.

Eye irritation / corrosion
Key study
In the GLP and guideline-conform in vivo eye irritation study conducted in rabbits (Schreiter 1999) 4-phenylbutan-2-one is considered to be not irritating to the eye. All animals showed slight conjunctival effects at the examinations occurring 1 and 24 hours after treatment. However, all effects were transient and reversible within 48 hours after treatment. Based on these results it is concluded that the substance is non-irritating to the rabbit eye and no classification proposal is required.

Justification for selection of skin irritation / corrosion endpoint:

The most reliable GLP-study in vivo with principles closest to those of OECD TG 404 was chosen as key study.

Justification for selection of eye irritation endpoint:

The key study is a reliable GLP-study according to OECD TG 405.

Justification for classification or non-classification

- skin irritation/corrosion:

Based on the assessment of 4-phenylbutan-2-one, the results of two in vivo studies did not show any skin irritation potential of the tests substance. Accordingly, classification according to Council Directive 2001/59/EC (28th ATP of Directive 67/548/EEC) and CLP (Regulation (EC) No 1272/2008 of the European Parliament and of the Council) as implementation of UN-GHS in the EU is not required.

 

- eye irritation/corrosion:

Based on the assessment of 4-phenylbutan-2-one, the respective study did not show any corrosive or irritating potential to the eye. Accordingly, classification according to Council Directive 2001/59/EC (28th ATP of Directive 67/548/EEC) and CLP (Regulation (EC) No 1272/2008 of the European Parliament and of the Council) as implementation of UN GHS in the EU is not required.