4-nitrobenzoic 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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: well performed GLP and OECD guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1987

Report date:

1987

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

4-nitrobenzoic acid

EC Number:

200-526-2

EC Name:

4-nitrobenzoic acid

Cas Number:

62-23-7

Molecular formula:

C7H5NO4

IUPAC Name:

4-nitrobenzoic acid

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:

S. typhimurium TA 1538

Species / strain 3

Species / strain / cell type:

E. coli WP2 uvr A

Metabolic activation:

with and without

Metabolic activation system:

Aroclor 1254(R) induced rat liver S9-mix

Test concentrations with justification for top dose:

Experiment I: 0, 4, 20, 100, 500, 2 500, 10 000 µg/plate
Experiment II: 0, 4, 20, 100, 500, 1 000, 2 500 (5 000) µg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- the test substance was dissolved in 100 µL respectively

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 9-aminoacridine, N-methyl-N-nitro-N-nitrosoguanidine, sodium azide, 2-nitrofluorene, 2-aminoanthracene, benzo[a]pyrene

Remarks:

without metabolic activation

Details on test system and experimental conditions:

METHOD OF APPLICATION:
in agar (plate incorporation)

DURATION
- Exposure duration: incubation for at least 48 to 72 hours

NUMBER OF REPLICATIONS: 3 plates per strain and dose level, including controls, two independent experiments

Evaluation criteria:

negative result: no significant and no dose dependant increase in the number of revertant colonies

Statistics:

Arithmetic means of the counted colonies were calculated.

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:

positive

Remarks:

TA 1535 only

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Test results 2

Species / strain:

S. typhimurium TA 1538

Metabolic activation:

with and without

Genotoxicity:

positive

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Test results 3

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

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'.

Any other information on results incl. tables

	Experiment I			Experiment II
Metabolic activation	Dose µg/plate	TA 1535	TA 1538	Dose µg/plate	TA 1535	TA 1538
		Number of colonies (mean)			Number of colonies (mean)
	0	10	12	0	23	13
	4	14	13	4	21	8
	20	15	8	20	25	20
	100	11	16	100	18	21
	500	25*	22	500	26	29
	2 500	0*	0	1 000	3*	42
	10 000	0*	0	2 500	0*	0*
X	0	12	23	0	24	29
X	4	11	26	4	16	28
X	20	9	27	20	17	32
X	100	14	27	100	13	29
X	500	21	26	500	33	34
X	2 500	56*	27*	2 500	0*	10*
X	10 000	0*	0*	5 000	0*	6*

*: incomplete bacterial lawn

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
positive

The test item did exert weak mutagenic activity in strains TA 1535 and TA 1538 of the Salmonella typhimurium and Escherichia coli reverse mutation assay (plate incorporation test) with and without metabolic activation.

Executive summary:

Mutagenic activity of the test item was investigated in Salmonella typhymurium strains 1535, 1537, 98, 100 and 1538 as well as Escherichia coli WP2 uvrA with and without metabolic activation (induced rat liver S9-mix) at concentrations of 0 to 10 000 µg/plate. Under the conditions tested the test compound did cause an increase in the number of revertant colonies of strains TA 1535 and TA 1538 with and without metabolic activation.

The test substance proved to be toxic at doses of 500 µg/plate and higher.

Therefore the test item is considered mutagenic under the conditions in this bacterial reverse mutation assay.