Pentane-2,4-dione

Endpoint summary

Description of key information

2,4-Pentanedione was investigated for beeing skin or eye irritating. Studies with single exposure to animals according to OECD Guidelines show no potential of the substance for beeing either skin or eye irritating. No test has been done on the question of beeing irritating to the respiratory tract. 

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

A skin irritation study was conducted in New Zealand White rabbits. A volume of 0.5 ml of undiluted test substance was applied on the dorsal skin of six rabbits (three males and three females) for 4 hours with occlusive dressing. Treated skin areas were inspected 1 hour and 1, 2, 3, 7 and 14 days after removal of the dressing. The scores were calculated according to Draize. One hour after removal of the occlusive dressing slight erythema were detectable in 5 animals with an average score of 0.8; after 24 hours erythema were detectable in 6 animals (average score 1.0); one hour after removal of the occlusive dressing slight and moderate edema formation was observable in 5 and 1 rabbits (average score 1.2), respectively; after 24 hours slight edema were still present in 5 rabbits (average score 0.8). After 48 and 72 hours five and three animals revealed just detectable erythema (average scores 0.8 and 0.5). Mild edema were observable at 48 and 72 hours in two and one animals (average scores 0.3 and 0.2). With the exception of mild desquamation detectable in 5 animals no skin irritations or other effects were present on day 7 (Ballantyne et al. 1986, Union Carbide Corp. Bushy Run Research Center 1985). According to the readings made the substance was overall evaluated as not irritating to the skin of rabbits. However, after repeated dermal application to rabbits local skin irritating effects have been observed.

The eye irritation potential of 2,4-pentanedione was investigated in rabbits. A volume of 0.1 ml of undiluted test substance was applied to the eyes of six female New Zealand White rabbits. Eyes were inspected 1, 4, 24, 48 and 72 hours as well as 7 days post-instillation, respectively. The scores were calculated according to Draize. Opacities of the cornea were not detectable at any time. One hour after application of the material, slight redness of the conjunctivae was observable in 5 animals (average score 0.8), slight and moderate chemosis in 2 and 1 animals (average score 0.7), respectively, slight and moderate discharge in 2 and 3 animals (average score 1.3), respectively, and slight inflammation of the iris in 2 animals (average score 0.3). Four hours after application of the material, slight inflammation of the iris was evident in 1 animals (score 0.2), slight redness of the conjunctivae in 4 animals (average score 0.7), slight and moderate chemosis in 2 and 1 animals (average score 0.7), respectively, slight and moderate conjunctival discharge was observable in 3 and 2 animals (average score 1.2), respectively. Twenty-four hours postinstillation all effects seen were completely reversible (Ballantyne et al. 1986, Union Carbide Corp. Bushy Run Research Center 1985). On the basis of the readings made throughout the study the material resulted in minor transient irritation with no corneal involvement. According to the grading system available the material has not to be evaluated as an eye irritating substance. [modified from OECD SIDS Dossier]

Justification for classification or non-classification

2,4-Pentanedione was investigated for beeing skin or eye irritating. Studies with single exposure to animals according to OECD Guidelines show no potential of the substance for beeing either skin or eye irritating. However repeated dose investigations show a slight potential of the substance for beeing irritating to the skin. This does not justify a classification as beeing skin irritating.