4''-Ethyl-2'-fluor-4-propyl-1,1':4',1''-terphenyl

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:

Feb 05, 2003 - Jul 21, 2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

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:

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

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

4'-ethyl-3-fluoro-4-(4-propylphenyl)-1,1'-biphenyl

EC Number:

619-171-3

Cas Number:

95759-44-7

Molecular formula:

C₂₃H₂₃F

IUPAC Name:

4'-ethyl-3-fluoro-4-(4-propylphenyl)-1,1'-biphenyl

Test material form:

solid: bulk

Specific details on test material used for the study:

Purity : > 99,9 %

Method

Target gene:

Salmonella: histidine operon
E coli. tryptophane operon

Species / strain

Species / strain 1

Species / strain / cell type:

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

Species / strain 2

Species / strain / cell type:

S. typhimurium TA 102

Metabolic activation:

with and without

Metabolic activation system:

S9 mix from Aroclor 1254 pretreated rats

Test concentrations with justification for top dose:

1st series: 5.00, 15.8, 50.0, 158, 500, 1580, and 5000 µg/plate
2nd series: 5.00,15.8, 50.0, 158, and 500 µg/plate

Vehicle / solvent:

acetone

Controls

Controls 1

Positive controls:

yes

Positive control substance:

benzo(a)pyrene

other:

Remarks:

in presence of S9 mix

Controls 2

Positive controls:

yes

Positive control substance:

9-aminoacridine

N-ethyl-N-nitro-N-nitrosoguanidine

cumene hydroperoxide

other:

Remarks:

absence of S9 Mix

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Preincubation period: 3-5 hours
- Exposure duration: about 2 days


SELECTION AGENT (mutation assays): Histidine, Tryptophane

NUMBER OF REPLICATIONS:
Negative control 6
Test material 3
Positive controls 3


NUMBER OF CELLS EVALUATED: about 1e9


DETERMINATION OF CYTOTOXICITY
- Method: other: background cytotox

Rationale for test conditions:

According to guideline

Evaluation criteria:

- valid assay (cf. laboratory historical data)
- no or weak increase in revertant colonies = negative
- clear, dose dependent (over at least two concentrations), and reproducible increase in revertant colonies= positve

Statistics:

not applied

Results and discussion

Test results

Test results 1

Key result

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not examined

Positive controls validity:

valid

Test results 2

Key result

Species / strain:

S. typhimurium TA 102

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not examined

Positive controls validity:

valid

Test results 3

Key result

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not examined

Positive controls validity:

valid

Test results 4

Key result

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not examined

Positive controls validity:

valid

Test results 5

Key result

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not examined

Positive controls validity:

valid

Test results 6

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

True negative controls validity:

not examined

Positive controls validity:

valid

Additional information on results:

Precipitation occured at concentrations or equal 500 µg/plate. Toxicity to bacteria was not observed

Applicant's summary and conclusion

Conclusions:

With and without addition of S9 mix as the external metabolizing system, the test material was not mutagenic under the experimental conditions described.

Executive summary:

Purpose

The purpose of this in vitro reverse gene mutation test is to identify agents that cause mutations in bacteria cells thus providing information on possible health hazards for the test material and serve as a rational basis for risk assessment to the genotoxic potential of the test item in man.

 

Study Design

The investigations for mutagenic potential were performed using Salmonella typhimurium tester strains TA 98, TA 100, TA 102, TA 1535 and TA 1537, and Escherichia coli WP2 uvrA pkM101. The plate incorporation test with and without addition of liver S9 mix from Aroclor 1254-pretreated rats was used. Two independent experimental series were performed for all strains. In the series with S9 mix, 10 % or 30 % S9 in the S9 mix were used inn the 1st and 2nd series, respectively.

 

Results

The test material was dissolved in DMSO and tested at concentrations ranging from 5.00 to 5000 pg/plate. Precipitation of the test material on the agar plates and toxicity to the bacteria was not observed.

 

Daunomycin, N-ethyl-N'-nitro-N-nitroso-guanidine, 9-aminoacridine and cumene hydroperoxide served as strain specific positive control compounds in the absence of S9 mix. 2-Aminoanthracene and benzo[a]pyrene were used for testing the bacteria and the activity of the S9 mix. Each treatment with the substances used as positive controls led to a clear increase in revertant colonies, thus showing the expected reversion properties of all strains and good metabolic activity of the S9 mix used.

 

No increase in revertant colonies was obtained after treatment with the test material up to the highest concentrations investigated, thus showing the absence of mutagenic potential in vitro with and without external metabolizing system.

 

Conclusions

With and without addition of S9 mix as the external metabolizing system, the test material was not mutagenic under the experimental conditions described.