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Administrative data

Description of key information

Key value for chemical safety assessment

Skin sensitisation

Endpoint conclusion
Additional information:

From study record RAR:

In a very doubtful guinea pig test o-anisidine revealed a weak sensitisation potential (intra- and epicutaneous application of 0.5 or 2.5 mg/kg bw resp.; no further information available). In a local lymph node assay using a standard test protocol a dose related unequivocal positive response for o-aminophenol was found (o-aminophenol can be formed in the metabolism of o-anisidine as was shown in in vitro studies).This metabolite of o-anisidine also gave a positive result in a modified single injection adjuvant test. However, one valid and well-documented guinea pig maximization test on a structural related compound o-phenetidine (1 -amino-2 -ethoxy-benzene) showed negative test results. In their overall evaluation the authors of the RAR state that "uncertainty remains as to whether or not o-anisidine possesses skin sensitizing potential and further information would be required to resolve this issue."

Latest data:

A subsequent recently finalized LLNA (OECD 429, reliability 1) revealed no clear results as well. Based on S.I. values one of which is slightly above 3, o-Anisidine would formally have to be regarded as a skin sensitiser. But due to missing dose response relationship, potentially irritating effects, and the impairment by an unexplained death of one animal this interpretation seems not to be entirely reliable. Thus the final conclusion is that the outcome of this study is considered to be equivocal.

 

As a consequence the previous RAR conclusion "uncertainty remains as to whether or not o-anisidine possesses skin sensitizing potential and further information would be required to resolve this issue." remains still valid.

Migrated from Short description of key information:
Available data are equivocal and do not allow a final conclusion on skin sensitizing properties.

Justification for classification or non-classification

Skin sensitization:

Based on the equivocal data available which allow no final conclusion and in view of the existing classification which guaranties a high protection level an additional classification as skin sensitizer seems dispensable.