4-Methylsulfonyl-2-nitro benzoic acid

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1996-02-02 to 1996-02-15

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: well performed OECD and GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1996

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 472 (Genetic Toxicology: Escherichia coli, Reverse Mutation Assay)

Deviations:

no

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

4-methanesulfonyl-2-nitrobenzoic acid

EC Number:

601-017-1

Cas Number:

110964-79-9

Molecular formula:

C8 H7 N1 O6 S1

IUPAC Name:

4-methanesulfonyl-2-nitrobenzoic acid

Details on test material:

- Name of test material (as cited in study report): MNBA (2-nitro-4-methylsulfonyl benzoic acid)
- Physical state: solid
- Analytical purity: 97.0 % (w/w)
- Lot/batch No.: WRC15483-30-1
- Storage condition of test material: ambient temperature in the dark

Method

Species / strain

Species / strain / cell type:

other: Salmonella typhimurium TA1535, TA1537, TA98 and TA100, Escherichia coli WP2P and WP2P uvrA

Metabolic activation:

with and without

Metabolic activation system:

S9 was prepared from male Sprague Dawley rats, dosed once daily (by oral gavage) for 3 days with a combined Phenobarbital (80mg/kg bodyweight) and P-Naphthoflavone (lOOmg/kg) corn oil solution.

Test concentrations with justification for top dose:

100, 200, 500, 1000, 2500, 5000 (MICROGRAMS/PLATE)

Vehicle / solvent:

DMSO

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: Acridine Mutagen ICR191, 2-Aminoanthracene, Daunomycin HC1, N-Ethyl-N'-nitro-N-nitrosoguanidine, Mitomycin C, Sodium Azide

Evaluation criteria:

A positive response in an individual experiment is achieved when one or both of the following criteria are met:
a) a statistically significant dose-related increase in the mean number of revertant colonies is obtained;
b) a two-fold or greater increase in the mean number of revertant colonies (over that observed for the concurrent solvent control plates) which is statistically significant, is observed at one or more concentrations.

Results and discussion

Test results

Species / strain:

other: Salmonella typhimurium TA1535, TA1537, TA98 and TA100, Escherichia coli WP2P and WP2P uvrA

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

Plate incorporation 2500 µg: TA 1535 -S9, TA 1537 -S9, TA 98 -S9, TA 100 -S9, WP2P -S9 / 5000 µg: WP2P uvra -S9 Pre-incubation 5000 µg: TA 1535 -S9, TA 1537 -S9, TA 100 -S9, WP2P -S9, WP2P uvra -S9

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

Under the conditions of this assay, MNBA gave a negative, ie non-mutagenic response in S.typhimurium strains TA1535, TA1537, TA98 and TA100 and E.coli strains WP2P and WP2P uvrA in both the presence and absence of S9-mix. substances

Executive summary:

MNBA (2-nitro-4-methylsulfonyl benzoic acid) was evaluated in a bacterial mutagenicity assay over a range of concentrations using four strains of Salmonella typhimurium (TA1535, TA1537, TA98 and TA100) and two strains of Escherichia coli (WP2P and WP2P uvrA) in the presence and absence of a rat liver-derived metabolic activation system (S9-mix), following Plate incorporation and Pre-incubation potocols.

In two separate experiments, the test substance did not induce any significant, reproducible increases in the observed numbers of revertant colonies in any of the tester strains used, either in the presence or absence of S9-mix. The sensitivity of the test system, and the metabolic activity of the S9-mix, were clearly demonstrated by the increases in the numbers of revertant colonies induced by positive control substances.

It is concluded that, under the conditions of this assay, MNBA gave a negative, ie non-mutagenic response in S.typhimurium strains TA1535, TA1537, TA98 and TA100 and E.coli strains WP2P and WP2P uvrA in both the presence and absence of S9-mix. substances