Benzenesulfonic acid, 4-hydroxy-, 2,6-dimethylphenyl ester

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: genome mutation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

7-16 December 2011

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Data have been generated according to current internationally recognised study guidelines and in accordance with GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

2,6-dimethylphenyl 4-hydroxybenzene-1-sulfonate

Cas Number:

1364731-90-7

Molecular formula:

C14H14O4S

IUPAC Name:

2,6-dimethylphenyl 4-hydroxybenzene-1-sulfonate

Method

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

S9

Test concentrations with justification for top dose:

Concentrations of 5000; 2500; 1000; 316; 100; 31.6 and 10 μg/plate were examined in the Range Finding Test. Based on the results of the Range Finding Test, the test item concentrations in the Initial Mutation Test were 1581; 500; 158.1; 50; 15.81, 5 and 1.581 μg/plate. In the Confirmatory Mutation Test, concentrations of 1581; 500; 158.1; 50; 15.81, 5, 1.581 and 0.5 μg/plate were examined.

Vehicle / solvent:

The behaviour of the test item solutions with the solution of top agar and phosphate buffer was examined in a preliminary solubility test. Dimethyl sulfoxide was used as solvent to prepare the stock formulation of the test material. Test solutions were freshly prepared at the beginning of the experiments in the testing laboratory by diluting the stock formulation using the selected vehicle.

Controls

Negative solvent / vehicle controls:

yes

Remarks:

DMSO and distilled water

Positive controls:

yes

Positive control substance:

9-aminoacridine

sodium azide

methylmethanesulfonate

other: 4-nitro-1,2-phenylene-diamine (NPD), 2-aminoanthracene (2AA)

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Based on the results of the Solubility Test and available information, the test item was dissolved in Dimethyl sulfoxide (DMSO). Concentrations of 5000; 2500; 1000; 316; 100; 31.6 and 10 μg/plate were examined in the Range Finding Test. Based on the results of the Range Finding Test, the test item concentrations in the Initial Mutation Test were 1581; 500; 158.1; 50; 15.81, 5 and 1.581 μg/plate. In the Confirmatory Mutation Test, concentrations of 1581; 500; 158.1; 50; 15.81, 5, 1.581 and 0.5 μg/plate were examined.

In the Initial Mutation Test and Confirmatory Mutation Test, none of the observed revertant colony numbers were above the respective biological threshold value. There were no consistent dose-related trends and no indication of any treatment effect. In all test item treated groups, the numbers of revertant colonies were below the biological relevance when compared with the solvent controls and were within the historical control range and were within the normal biological variability of the test system.

Strong inhibitory, cytotoxic effect of the test item was observed in the Initial Mutation Test and Confirmatory Mutation Test in all strains with and without metabolic activation at the two or three highest concentrations.

Precipitate / slight precipitate was observed on the plates in the Confirmatory Mutation Test in all examined strains at the highest concentration with and without metabolic activation.

The mean values of revertant colonies of the solvent control plates were within the historical control range, the reference mutagens showed the expected increase in the number of revertant colonies, the viability of the bacterial cells was checked by a plating experiment in each test. At least five analyzable concentrations were presented in all strains of the main tests. The tests were considered to be valid.

The reported data of this mutagenicity assay show that under the experimental conditions applied the test item did not induce gene mutations by base pair changes or frameshifts in the genome of the strains used.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

The test item had no mutagenic activity in the bacterium tester strains under the test conditions used in this study.

Executive summary:

The mutagenic potential has been assessed by exposure to S. typhimurium TA 1535, TA 1537, TA 98 and TA 100 and E. coli WP2 uvr A in DMSO with and without S9 metabolic activations in accordance with the OECD 471 test guideline in compliance with GLP. Under the conditions of the test, the test substance was shown to have no mutagenic activity to bacterium tester strains.