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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Type of information:
experimental study
Adequacy of study:
key study
Study period:
April 02 -April 04, 1991
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
comparable to guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1991
Report date:
1991

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
GLP compliance:
no
Type of assay:
bacterial reverse mutation assay

Test material

Constituent 1
Chemical structure
Reference substance name:
(trans(trans))-4'-but-3-enyl-4-(4-methylphenyl)-bicyclohexyl
EC Number:
429-580-7
EC Name:
(trans(trans))-4'-but-3-enyl-4-(4-methylphenyl)-bicyclohexyl
Cas Number:
129738-42-7
Molecular formula:
Hill formula: C23H34 CAS formula: C23H34
IUPAC Name:
(1s,4r)-4-(but-3-en-1-yl)-4'-(4-methylphenyl)-1,1'-bi(cyclohexane)

Method

Target gene:
histidine for S. thyphimurium
tryptophan for E. coli
Species / strainopen allclose all
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Species / strain / cell type:
E. coli WP2 uvr A
Metabolic activation:
with and without
Metabolic activation system:
Type and composition of metabolic activation system:
- source of S9 : Bioscience Research Laboratory, Kikkoman Corporation (S9; produced on Jan. 11, 1991,Lot No:RAA-248)
- method of preparation of S9 mix: A 9,000 g supernatant (S9), prepared from liver tissue of male Sprague-Dawley rats (7 weeks old) induced with phenobarbital and 5,6-benzoflavone was used. For 1 mL: 0.1 mL S9 + 8 µmol MgCl2 + 33 µmol KCl + 5 µmol G-6-P + 4 µmol NADH + 4 µmol NADPH + 0.5 mL 0.2 M Sodium phosphate buffer (pH 7.4)
- concentration of S9 mix: 0.1 mL S9 in 1 mL S9 mix
- volume of S9 mix added: 0.5 mL per plate with metabolic activation
Test concentrations with justification for top dose:
0, 150, 500, 1500 and 5000 µg/plate
Vehicle / solvent:
The test substance was dissolved up to 50 mg/mL in acetone, and was used for the assay immediately after diluting with the same solvent.
Controls
Untreated negative controls:
no
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
9-aminoacridine
sodium azide
furylfuramide
other: 2-aminoanthracene (2-AA)
Details on test system and experimental conditions:
NUMBER OF REPLICATIONS:
- Number of cultures per concentration: duplicate
- Number of independent experiments : 1

METHOD OF TREATMENT/ EXPOSURE:
- Test substance added in agar (plate incorporation)

FOR GENE MUTATION:
- Plates were incubated for 48 h at 37 °C.

METHODS FOR MEASUREMENT OF CYTOTOXICITY
- not examined
Evaluation criteria:
The results were judged to be positive when the revertants were twice or more that of the negative control, and when dose dependency or reproducibility were observed in the increase of revertants at least in one strain.
Statistics:
The mean of two plates counted was calculated.

Results and discussion

Test resultsopen allclose all
Key result
Species / strain:
S. typhimurium TA 1535
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity nor precipitates, but tested up to recommended limit concentrations
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
True negative controls validity:
not examined
Positive controls validity:
valid
Key result
Species / strain:
S. typhimurium TA 98
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
not determined
Remarks:
but tested up to the recommended limit concentration
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
True negative controls validity:
not examined
Positive controls validity:
valid
Key result
Species / strain:
S. typhimurium TA 1537
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
not determined
Remarks:
but tested up to the recommended limit concentration
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
True negative controls validity:
not examined
Positive controls validity:
valid
Key result
Species / strain:
S. typhimurium TA 100
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
not determined
Remarks:
but tested up to the recommended limit concentration
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
True negative controls validity:
not examined
Positive controls validity:
valid
Key result
Species / strain:
E. coli WP2 uvr A
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
not determined
Remarks:
but tested up to the recommended limit concentration
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
True negative controls validity:
not examined
Positive controls validity:
valid
Additional information on results:
Ames test:
Please refer to "Attached background material" for:
- Individual plate counts
- Mean number of revertant colonies per plate

Applicant's summary and conclusion

Conclusions:
The test item was not mutagenic in the bacterial reverse mutation study with and without metabolic activation.
Executive summary:

An in vitro bacterial reverse mutation study was conducted similar to OECD 471. In one plate incorporation test the test item was applied at concentrations of 0, 150, 500, 1500 and 5000 µg/plate to Salmonella typhimurium (TA100, TA1535, TA98, TA1537) and Escherichia coli (WP2 uvrA) strains with and without metabolic activation using S9 mix. There were no increasing number of revertants observed for any strains and any concentration of the test item. The positive control substances increased the number of mutants twice or more the negative control in each strains. Under the test conditions the test item did not show mutagenic potential in the presence and absence of metabolic activation.