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Administrative data

Key value for chemical safety assessment

Additional information

There are 5 different in vitro genetic toxicity assays and 2 different in vivo genetic toxicity assays conducted with hydrotrope substances, principally sodium xylene sulphonate. The key studies are as follows:

 

An in vitro bacterial cell gene mutation study (Ames Test) on sodium xylene sulphonate with four strains of Salmonella, all with and without S9 metabolic activation, positive and negative controls, and 5 exposure concentrations of the test substance. The genotoxicity results were negative for all conditions.

An in vitro mammalian cell gene mutation study (Mouse Lymphoma) on sodium xylene sulphonate with and without S9 metabolic activation, positive and negative controls, a DMSO vehicle, and 5 exposure concentrations of the test substance. The genotoxicity results were negative without activation and equivocal with activation (one replicate was positive and the 2nd replicate was negative). The study conclusion was "negative genotoxicity".

A mammalian cell DNA damage assay (Sister Chromatid Exchange in Chinese Hamster Ovary) on sodium xylene sulphonate with and without Aroclor 1254 activation, positive and negative controls, using a DMSO vehicle, and 5 exposure concentrations of the test substance. The genotoxicity results were negative with activation and positive without activation (clastogenic at doses of 2513 micrograms active per milliliter and higher). The study conclusion was not genotoxic with metabolic activation.

A mammalian cell chromosome aberration study on sodium xylene sulphonate in Chinese Hamster Ovary cells with and without Aroclor 1254 metabolic activation, positive and negative control, tested up to limit concentrations. The test material was not genotoxic in this assay.

An in vivo micronucleus study on sodium cumene sulphonate where mice were dosed by oral gavage at 4467 mg/kg bw. The study gave a negative result.

 

The other supporting studies also gave negative results.


Short description of key information:
There are 5 different in vitro genetic toxicity assays and 2 different in vivo genetic toxicity assays conducted with hydrotrope category substances, principally sodium xylene sulphonate. The assays are Ames Test, mouse lymphoma mammalian gene mutation, Chinese hamster sister chromatid exchange, Chinese hamster ovary mammalian chromosome aberration, in vivo mouse micronucleus bone marrow chromosome analysis, and in vivo mammalian erythrocyte micronucleus. All are guideline studies, conducted according to GLP requirements and fully documented. The conclusion from the battery of 7 different validated assays is the hydrotrope substances are not mutagenic or genotoxic.

Endpoint Conclusion: No adverse effect observed (negative)

Justification for classification or non-classification

On the basis of the negative results obtained across a range of in vitro and in vivo assays, there is no justification for classification.