2-bromo-4'-chloro-2'-(o-fluorobenzoyl)acetanilide

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

27.04.2017 - 06.06.2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

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 (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

2-bromo-4'-chloro-2'-(o-fluorobenzoyl)acetanilide

EC Number:

216-437-7

EC Name:

2-bromo-4'-chloro-2'-(o-fluorobenzoyl)acetanilide

Cas Number:

1584-62-9

Molecular formula:

C15H10BrClFNO2

IUPAC Name:

2-bromo-4'-chloro-2'-(o-fluorobenzoyl)acetanilide

Test material form:

solid: particulate/powder

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 0190161002
- Expiration date of the lot/batch: 02.08.2019
- Purity test date: 17.03.2017

Method

Species / strain

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and E. coli WP2

Metabolic activation:

with and without

Metabolic activation system:

phenobarbital/β-naphthoflavone induced rat liver S9

Test concentrations with justification for top dose:

Experiment I (Plate Incorporation):
All strains with/without S9 mix: 3; 10; 33; 100; 333; 1000; 2500; and 5000 μg/plate
Experiment II (Pre-Incubation):
All strains without S9 mix: 10; 33; 100; 333; 1000; 2500; and 5000 μg/plate
All strains with S9 mix: 1; 3; 10; 33; 100; 333; 1000; and 2500 μg/plate

The test item precipitated in the overlay agar in the test tubes from 100 to 5000 μg/plate with and without S9 mix in experiment I and in experiment II from 100 to 5000 μg/plate without S9 mix and from 333 to 2500 μg/plate with S9 mix. Precipitation of the test item in the overlay agar on the incubated agar plates was observed at a concentration of 333 μg/plate up to the highest investigated dose in both experiments with and without S9 mix. The undissolved particles had no influence on the data recording.

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO; deionised water

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

sodium azide

methylmethanesulfonate

other: 4-nitro-o-phenylene-diamine; 2-aminoanthracene

Details on test system and experimental conditions:

METHOD OF APPLICATION:
- Experiment I (Plate Incorporation)
- Experiment II (Pre-Incubation)

DURATION:
Experiment II:
- Preincubation period: 1 h
- Exposure duration: 48 h

NUMBER OF REPLICATIONS: 3

DETERMINATION OF CYTOTOXICITY
Toxicity of the test item can be evident as a reduction in the number of spontaneous revertants or a clearing of the bacterial background lawn.

Evaluation criteria:

A test item is considered as a mutagen if a biologically relevant increase in the number of revertants exceeding the threshold of twice (strains TA 98, TA 100, and WP2 uvrA) or thrice (strains TA 1535 and TA 1537) the colony count of the corresponding solvent control is observed.
A dose dependent increase is considered biologically relevant if the threshold is exceeded at more than one concentration.
An increase exceeding the threshold at only one concentration is judged as biologically relevant if reproduced in an independent second experiment.
A dose dependent increase in the number of revertant colonies below the threshold is regarded as an indication of a mutagenic potential if reproduced in an independent second experiment. However, whenever the colony counts remain within the historical range of negative and solvent controls such an increase is not considered biologically relevant.

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

Experiment 1: 5000 µg/plate (with/without S9), Experiment II: 5000 µg/plate (without S9) or 2500 µg/plate (with S9)

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

Experiment 1: 5000 µg/plate (without S9) or 1000-5000 µg/plate (with S9), Experiment II: 1000-2500 µg/plate (with S9)

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 3

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

Experiment 1: 5000 µg/plate (without S9) or 1000-5000 µg/plate (with S9), Experiment II: 1000-2500 µg/plate (with S9)

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 4

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

Experiment 1: 333-5000 µg/plate (with S9), Experiment II: 333-2500 µg/plate (with S9)

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 5

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

Experiment 1: 2500-5000 µg/plate (with S9), Experiment II: 1000-2500 µg/plate (with S9)

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

No substantial increase in revertant colony numbers of any of the five tester strains was observed following treatment with 2-Bromoacetamido-2´-fluoro-5-chlorobenzophenone at any concentration level, neither in the presence nor absence of metabolic activation (S9 mix). A slight increase in the number of revertant colonies was observed in experiment I in strain WP2 uvrA without S9 mix, but the threshold of twice the colony number of the corresponding solvent control was not reached. Since colony count in the corresponding solvent control as compared to the concentrations is very low, it can be stated that this effect is caused by biological fluctuations at such low numbers and does not indicate a true mutagenic potential.

Applicant's summary and conclusion

Conclusions:

2-Bromoacetamido-2´-fluoro-5-chlorobenzophenone (BFB) is considered to be non-mutagenic in this Salmonella typhimurium and Escherichia coli reverse mutation assay.