1,1'-Biphenyl, 4-methyl-4'-(3E)-3-penten-1-yl-

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:

2004-08-13 to 2004-09-11

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2004

Report date:

2004

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:

-

EC Number:

473-310-0

EC Name:

-

Cas Number:

478385-88-5

Molecular formula:

C18H20

IUPAC Name:

4-methyl-4'-[(3E)-pent-3-en-1-yl]-1,1'-biphenyl

Method

Target gene:

HIS operon (S. thyphimurium)
TRY operon (E. coli)

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1535

Details on mammalian cell type (if applicable):

his G 46, uvrB, rfa

Additional strain / cell type characteristics:

other: mutations in the histidine operon

Species / strain 2

Species / strain / cell type:

S. typhimurium TA 1537

Details on mammalian cell type (if applicable):

his C 3076, uvrB, rfa

Additional strain / cell type characteristics:

other: mutations in the histidine operon

Species / strain 3

Species / strain / cell type:

S. typhimurium TA 98

Details on mammalian cell type (if applicable):

his D 3052, uvrB, rfa + R-factor

Additional strain / cell type characteristics:

other: mutations in the histidine operon

Species / strain 4

Species / strain / cell type:

S. typhimurium TA 100

Details on mammalian cell type (if applicable):

his G 46, uvrB, rfa + R-factor

Additional strain / cell type characteristics:

other: mutations in the histidine operon

Species / strain 5

Species / strain / cell type:

S. typhimurium TA 102

Details on mammalian cell type (if applicable):

his G 428, rfa + R-factor

Additional strain / cell type characteristics:

other: mutations in the histidine operon

Species / strain 6

Species / strain / cell type:

E. coli WP2

Details on mammalian cell type (if applicable):

his C 3076, uvrB, rfa

Additional strain / cell type characteristics:

other: mutations in the tryptophan operon

Metabolic activation:

with and without

Metabolic activation system:

rat liver homogenate (S9 mix) with standard co-factors with metabolic activation (Aroclor)

Test concentrations with justification for top dose:

The test material concentrations were used selected according to the EC and OECD guidelines for this test system and the requirements of the Labor Ministry of Japan:
1. Series: 5, 15.8, 50, 158, 500, 1580, and 5000 µg/plate
2. Series: 1.58, 5.00, 15.8, 50.0, and 158 µg/plate

Vehicle / solvent:

Acetone

Controls

Controls 1

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

benzo(a)pyrene

Controls 2

Positive controls:

yes

Positive control substance:

cumene hydroperoxide

Controls 3

Positive controls:

yes

Positive control substance:

N-ethyl-N-nitro-N-nitrosoguanidine

Controls 4

Positive controls:

yes

Positive control substance:

9-aminoacridine

Controls 5

Positive controls:

yes

Positive control substance:

other: daunomycine

Controls 6

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene

Evaluation criteria:

The assessment of test material-induced effects is dependent on the number of spontaneous revertants of each bacterial strain (solvent controls) and the increase in the number of revertants at the test material concentration which shows the highest number of colonies. The criteria provided in table 1 in "any other information on materials and methods", based upon the historical controls of the laboratory and statistical considerations, were established.

Interpretations:
A test material was to be defined as negative or non-mutagenic in this assay if
• the assay was to be considered valid, and
• "no" or "weak increases" occurred in the test series performed ("weak increases" randomly occur due to experimental variation)

For valid data, the test material was considered to be positive or mutagenic if:
• the assay was to be considered valid, and
• a dose dependent (over at least two test material concentrations) increase in the number of re-vertants was induced, the maximal effect was a "clear increase", and the effects were reproduced at similar concentration levels in the same lest system or
• "clear increases" occurred al least at one test material concentration, higher concentrations showed strong precipitation or cytotoxicity, and the effects were reproduced at the same concentration level in the same test system.

Results and discussion

Test results

Test results 1

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

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 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

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 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

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 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

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 102

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

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:

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

True negative controls validity:

not examined

Positive controls validity:

valid

Any other information on results incl. tables

Please refer to background material attached.

Applicant's summary and conclusion

Conclusions:

The test material was not mutagenic under the test conditions with and without metabolic activation from induced rat liver S9 mix.

Executive summary:

The purpose of this assay was to provide 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. The investigations for the mutagenic potential of the test item were performed using Salmonella typhimurium tester strains TA 98, TA 100, TA 102, TA 1535 and TA 1537, and Escherichia coil WP2 uvrA. 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. In the two series with S9 mix, 10 or 30 % S9 in the S9 mix were used in the 1st and 2nd series, respectively. The test item was dissolved in acetone and tested at concentrations ranging from 1.58 to 5000 µg/plate. Precipitation of the test material on the agar plates occurred at concentrations 158 µg/plate. Toxicity to the bacteria was not observed. Daunomycin, N-ethyl-N'-nitro-N-nitrosoguanidine, 9-aminoacridine and cumene hydroperoxide served as strain specific positive control test materials 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 test materials 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.

In both series of experiments, each performed with and without the addition of rat liver S9 mix as the external metabolizing system, the test item showed no increase in the number of revertants of any bacterial strain. According to the criteria for negative and positive results predetermined in the Study Protocol, the test item was not mutagenic under the described experimental conditions. With and without addition of S9 mix as the external metabolizing system, the test item was not mutagenic under the experimental conditions described.