(6R-trans)-7-amino-3-methyl-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic 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:

1 February - 7 March, 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study is performed according to OECD Guideline 471 and EU method B.13/14 under GLP conditions. No relevant deviations reported.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2002

Report date:

2001

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:

EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)

Deviations:

no

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

22352-43-3

IUPAC Name:

22352-43-3

Constituent 2

Reference substance name:

7-aminodesacetoxycephalosporanic acid

IUPAC Name:

7-aminodesacetoxycephalosporanic acid

Constituent 3

Reference substance name:

244-87-1

IUPAC Name:

244-87-1

Details on test material:

- Name of test material (as cited in study report): ZOR-F
- Substance type: white to off-white powder
- Physical state: solid
- Analytical purity: 99.2%
- Impurities (identity and concentrations): delta-2-7-ADCA 0.13%, 6-APA 7 mg/kg
- Lot/batch No.: D210058
- Expiration date of the lot/batch: 01-12-2003
- Storage condition of test material: refrigerator, protected from light

Method

Target gene:

Histidine gene in S. Typhimurium
Tryptophan gene in E. Coli

Species/strain
S. Typhimurium TA 98/100/1535/1537
E. Coli WP2uvrA

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:

rat liver S9-mix

Test concentrations with justification for top dose:

Dose range test: 0, 3, 10, 33, 100, 333, 1000, 3330, 5000 µg/plate
Test 2/3: 0, 100, 333, 1000, 3330, 5000 µg/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: not reported

Controls

Untreated negative controls:

yes

Remarks:

DMSO

Negative solvent / vehicle controls:

yes

Remarks:

DMSO/Saqline

Positive controls:

yes

Positive control substance:

sodium azide

Remarks:

Migrated to IUCLID6: 9-aminoacridine, daunomycine, methylmethanesulfonate, 4-nitroquinoline N-oxide, 2-aminoanthracene

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Exposure duration: 48 h.

NUMBER OF REPLICATIONS: two independent experiments, dosages tested in triplicate

DETERMINATION OF CYTOTOXICITY
- Method: evaluation of bacterial background lawn, evaluation of revertant colonies, control of precipitation of active substance

Evaluation criteria:

A test substance is considered negative (not mutagenic) in the test if:
a) The total number of revertants in any tester strain at any concentration is not greater than two times the solvent control value, with or without metabolic activation.
b) The negative response should be reproducible in at least one independently repeated experiment.

A test substance is considered positive (mutagenic) in the test if:
a) It induces a number of revertant colonies, dose related, greater than two-times the number of revertants induced by the solvent control in any of the tester strains, either with or without metabolic activation.
However, any mean plate count of less than 20 is considered to be not significant.
b) The positive response should be reproducible in at least one independently repeated experiment.

Statistics:

See "evaluation criteria".

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:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative 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:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Precipitation: 3330, 5000 µg/plate ZOR-F precipitated in top agar, 5000 µg/plate ZOR-F precipitated on the plate at start of incubation. No precipitation observed at end of incubation.

RANGE-FINDING/SCREENING STUDIES:
Range finding: no reduction of the bacterial background lawn and no biologically relevant decrease in the number of revertants were observed.
Toxicity (test 2/3):
The bacterial background lawn was not reduced at any of the concentrations tested and no biologically relevant decrease in the number of revertants was observed.
Number of revertants:
All bacterial strains showed negative responses over the entire dose range, i.e. no dose-related, two-fold, increase in the number of revertants in two independently repeated experiments.

COMPARISON WITH HISTORICAL CONTROL DATA:
The negative and strain-specific positive control values were within the laboratory background historical control data ranges indicating that the test conditions were adequate and that the metabolic activation system functioned properly.

Any other information on results incl. tables

none

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

ZOR-F tested in the Salmonella typhimurium reverse mutation assay and in the E. Coli reverse mutation assay in concentrations up to 5000 µg/plate did not express any mutagenic potential.