Registration Dossier

Diss Factsheets

Administrative data

Key value for chemical safety assessment

Additional information

The test substance p-phenylbenzonitrile was tested for mutagenicity in the Salmonella typhimurium / Escherichia coli reverse mutation assay both in the standard plate test and in the preincubation test with and without the addition of a metabolizing system (S9 mix)

obtained from rat liver using the Salmonella strains TA 1535, TA 100, TA 1537, TA 98 and Escherichia coli WP2 uvrA (BASF 2012). The study followed OECD testing guideline 471 without deviations. It was performed under GLP. A strong bacteriotoxic effect (reduced his- or trp- background growth, decrease in the number of his+ or trp+ revertants, reduction in the titer) was observed in the standard plate test depending on the strain and test conditions from about 333 μg/plate onward.

In the preincubation assay bacteriotoxicity (reduced his- or trp- background growth, decrease in the number of his+ or trp+ revertants, reduction in the titer) was observed depending on the strain and test conditions from about 100 μg/plate onward. Test substance precipitation was found from about 1 000 μg/plate onward with and without S9 mix. In the first experiment with the standard plate test, tested doses were 0; 33; 100; 333; 1 000; 2 500 and 5 000 μg/plate with and without S9 mix and no mutagenicity was observed. In the repeat experiment also with standard design, bacteriotoxicity was observed and so a third experiment with pre-incubation was performed in which doses for the Salmonella strains were reduced to 0; 1; 3.3; 10; 33; 100 and 333 μg/plate. Overall, no increase in mutant frequency was observed.


Justification for selection of genetic toxicity endpoint
only study available.

Short description of key information:
The substance is not mutagenic in bacteria (OECD 471, GLP).

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

Dangerous Substance Directive (67/548/EEC)

The available study is considered reliable and suitable for classification purposes under 67/548/EEC. As a result the substance is not considered to be classified for mutagenicity under Directive 67/548/EEC, as amended for the 31st time in Directive2009/2/EG.

 

Classification, Labelling, and Packaging Regulation (EC) No. 1272/2008

The available experimental test data are reliable and suitable for classification purposes under Regulation 1272/2008. As a result the substance is not considered to be classified for mutagenicity under Regulation (EC) No. 1272/2008, as amended for the third time in Directive (EC 618/2012).