Pentane-2,4-dione

Endpoint summary

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

In a patch test study with human volunteers no information was available concerning gender and health status as well as a possible allergic predisposition of the test persons. Of the 12 persons tested three of them showed no, seven doubtful and two a positive reaction after an exposure period of 24 hours. No skin reactions were evident after 48 and 72 hours, respectively. The results observed in the human patch test were interpreted as an irritating rather than a sensitising effect and it was concluded by the authors that sensitisation might occur more frequently due to prolonged and close skin contact of pads containing the substance (Sterry and Schmoll 1985). However, due to both the poor description of the study and the very weak irritating potential of the compound a verification of the results described is lacking. [modified from OECD SIDS Dossier]

2,4-Pentanedione was tested for its ability to induce skin sensitization in an OECD 429 Local Lymph Node Assay (LLNA). Based on the results of the preliminary test the test item Acetylacetone was assayed for sensitising properties at concentrations of 12.5%, 25% and 50% (v/v). The vehicle used was Acetone/Olive Oil (AOO). Each mouse was treated by topical application of the prepared test item to the entire dorsal surface of each ear once daily over three consecutive days. Five days after the first topical application all mice were injected intravenously with 3H-methyl thymidine.

None of the three tested concentrations of the test item reached the stimulation index of 3. The stimulation index at a concentration of 12.5% was 0.9, the stimulation index at a concentration of 25% was 0.6 and the stimulation index at a concentration of 50% was 0.8. The EC3 value could not be stated, as all measure points were below the stimulation index of three. Results of radioactivity determination are supported by the second endpoint, means of the lymph node weights per group, which did not show dose-related increased values compared to negative control values as well. Considering the reported data of this sensitisation test it can be stated that the test item Acetylacetone causes no reactions identified as sensitisation, as the stimulation index was below 3.0 for each concentration tested (Wacker, 2009).

 

 

Migrated from Short description of key information:
From a volunteer study no clear assessment could be made concerning the question of skin sensitizing properties of 2,4-Pentanedione. A LLNA test performed with this material did not show any sensitizing properties of 2,4-Pentanedione.

Respiratory sensitisation

Endpoint conclusion

Additional information:

not assessed

Migrated from Short description of key information:
not assessed

Justification for classification or non-classification

From a volunteer study no clear assessment could be made concerning the question of skin sensitizing properties of 2,4-Pentanedione. A LLNA test performed with this material did not show any sensitizing properties of 2,4-Pentanedione. Therefore the properties of Acetylacetone are not sufficient to classify the substance as to the endpoint of skin classification.