Benzenesulfonic acid, 2-amino-5-methyl-, sodium salt (1:1)

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

1986

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP and OECD testing guideline compliant study, read across substance

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1986

Report date:

1986

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

Salmonella strains only, his mutation but no trp

Principles of method if other than guideline:

The tests were carried out in accordance with the method described by Ames et al. (1973a, 1973b, 1975)

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

4-aminotoluene-3-sulphonic acid

EC Number:

201-831-3

EC Name:

4-aminotoluene-3-sulphonic acid

Cas Number:

88-44-8

IUPAC Name:

2-amino-5-methylbenzenesulfonic acid

Details on test material:

Test material: TK 13 164 (4-Amino-toluol-3-sulfonsaeure)
Batch No.: Clayton 2/85
Purity: Commercial grade
Stability: Ensured by sponsor
Validity: Ensured by sponsor

Method

Target gene:

his- (Salmonella)

Species / strain

Species / strain / cell type:

other: S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102

Metabolic activation:

with and without

Metabolic activation system:

S9 from male rat liver, induced with phenobarbital and 5,6-benzoflavone

Test concentrations with justification for top dose:

0.08 - 5000 µg/plate, range in the toxicity test
20 - 5000 µg/plate, range in the mutagenicity test

Vehicle / solvent:

DMSO

Controls

Untreated negative controls:

not specified

Negative solvent / vehicle controls:

yes

True negative controls:

not specified

Positive controls:

yes

Positive control substance:

other: see details on test system below

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)
number of replicates: 3

Positive controls: without metabolic activation: for strain TA 98: daunorubicin-HCl, 5 and 10 µg/0.1 mL phosphate buffer; for strain TA 100: 4-nitroquinoline-N-oxide, 0.125 and 0.25 µg/0.1 ml phosphate buffer; for strain TA 102: mitomycin-C, 0.5 and 1.0 µg/0.1 ml bidistilled water; for strain TA 1535; sodium azide, 2.5 and 5.0 µg/0.1 ml bidistilled water; for strain TA 1537: 9(5)-aminoacridine hydrochloride monohydrate, 50 and 100 µg/0.1 ml DMSO.
The activation mixture was tested: with strains TA 98, TA 100, TA 1537: 2-aminoanthracene 5 µg/0.1 ml DMSO; with strain TA 102: 2-aminoanthracene, 20 µg/0.1 ml DMSO; with strain TA 1535: cyclophosphamide, 250 µg/0.1 ml phosphate buffer

Evaluation criteria:

The test substance is generally considered to be nonmutagenic if the colony count in relation to the negative control is not doubled at any concentration.

Results and discussion

Test results

Test results 1

Species / strain:

other: TA 1535, TA 1537, TA 98, TA 100 and TA 102

Metabolic activation:

with

Genotoxicity:

positive

Remarks:

in two independent experiments

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Test results 2

Species / strain:

other: TA 1535, TA 1537, TA 98, TA 100 and TA 102

Metabolic activation:

with

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Test results 3

Species / strain:

other: S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102

Metabolic activation:

without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Remarks on result:

other: strain/cell type: S. typhimurium TA 98

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Plate incorporation test (20 - 5000 µg/plate)
Strain	Metabolic activation system	mean revertants in Controls	maximum revertant factor	dose dependency	Assessment
TA 98	no	14	2.1	no	ambiguous
	yes	38	2.0	yes	positive
TA 100	no	140	1.0	no	negative
	yes	135	1.2	no	negative
TA 102	no	252	1.1	no	negative
	yes	315	1.0	no	negative
TA 1535	no	19	0.6	no	negative
	yes	10	1.5	no	negative
TA 1537	no	4	2.0	no	negative
	yes	25	1.1	no	negative
Plate incorporation test (20 - 5000 µg/plate)
Strain	Metabolic activation system	mean revertants in Controls	maximum revertant factor	dose dependency	Assessment
TA 98	no	16	1.0	no	negative
	yes	30	2.9	yes	positive
TA 100	no	121	1.2	no	negative
	yes	140	1.2	no	negative
TA 102	no	319	1.0	no	negative
	yes	362	1.1	no	negative
TA 1535	no	11	1.3	no	negative
	yes	12	1.4	no	negative
TA 1537	no	5	1.6	no	negative
	yes	15	1.2	no	negative

In the experiments carried out with microsomal activation, a slight increase in the number of back-mutant colonies was observed with strain TA 98 at the concentrations 1250 and 5000 µg/plate.

The slight increase in the number of back-mutant colonies observed with strain TA 1537 in the first experiment without microsomal activation at the concentration of 313 µg/plate is attributed to spontaneously occurring back-mutants.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
positive