Octane-1,2-diol

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Well documented and reported study fully adequate for assessment. The study was conducted according to internationally accepted technical guidelines and in compliance with GLP in a recognized contract research organization.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2008

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

of 1997

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

of 2000

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.5100 - Bacterial Reverse Mutation Test (August 1998)

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:

Octane-1,2-diol

EC Number:

214-254-7

EC Name:

Octane-1,2-diol

Cas Number:

1117-86-8

Molecular formula:

C8H18O2

IUPAC Name:

octane-1,2-diol

Method

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98 and TA 100

Additional strain / cell type characteristics:

other: essential amino acid requiring strains

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Additional strain / cell type characteristics:

other: essential amino acid requiring strain

Metabolic activation:

with and without

Metabolic activation system:

liver S9 mix from male Wistar rats treated by oral route on 3 consecutive days with Phenobarbital (80 mg/kg bw) and β-Naphtoflavone (100 mg/kg bw) for enzyme induction

Test concentrations with justification for top dose:

Pre-Experiment (Plate-incorporation Test):
0 (vehicle control), 3.16, 10.0, 31.6, 100, 316, 1000, 2500, 5000 µg/plate TA 98 and TA100 without and with metabolic activation (S9).

Experiments 1 (Plate-incorporation Test, including some of the assays from the pre-experiment) and 2 (Pre-incubation Test):
0 (vehicle control), 10.0, 31.6, 100, 316, 1000, 2500 and 5000 µg/plate (TA 98, TA100, TA1535, TA1537, WP2 uvrA without and with metabolic activation (S9).

Vehicle / solvent:

Dimethylsulfoxide (DMSO)
Justification for choice of solvent/vehicle:
DMSO was a suitable vehicle for exposure to the test material up to the maximum guideline recommended test material concentration of 5000 μg/plate. It was compatible with bacterial survival and S9 activity.

Controls

Controls 1

Untreated negative controls:

yes

Remarks:

distilled water

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

sodium azide

methylmethanesulfonate

other: 4-nitro-o-phenylene-diamine (4-NOPD)

Remarks:

Positive control substances for tests without metabolic activation (S9 mix): Methylmethanesulfonate for E. coli WP2 uvrA, sodium azide for S. typhimurium TA100 & TA 1535, 4-NOPD for S. typhimurium TA98 & TA 1537.

Controls 2

Untreated negative controls:

yes

Remarks:

distilled water

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene

Remarks:

Used for all strains in the tests with metabolic activation (S9 mix).

Details on test system and experimental conditions:

Plate-incoroporation tests were performed in the Pre-Experiment and Experiment 1, and pre-incubation tests in Experiment 2.
Precipitation of the test material was not evident at any test concentration and tester strain used in Experiments 1 and 2 (without and with metabolic activation).

Positive Control Substances:
sodium azide: positive control for TA 100 and TA 1535 without metabolic activation; vehicle = distilled water.
4-nitro-o-phenylene-diamine: positive control for TA 98 and TA 1537 without metabolic activation; vehicle = dimethylsulfoxide (DMSO).
methylmethanesulfonate: positive control for WP2 uvrA without metabolic activation; vehicle = distilled water.
2-aminoanthracene: positive control for TA 98, TA 100, TA 1535, TA 1537 and WP2 uvrA with metabolic activation; vehicle = DMSO.

Evaluation criteria:

Evaluation Criteria
Degree of increase in the number of revertant colonies in any tester strain. Dose dependency of any effects. Confirmation in independent repeat experiment.

An increase in number of revertant colonies is considered to be biologically relevant:
- if in tester strains TA 100 and/or WP2 uvrA the number of revertant colonies is at least twice higher,
- if in tester strains TA 98, TA 1535 and/or TA 1537 the number of revertant colonies is at least three times higher,
than the number of revertant colonies in the solvent/vehicle control.

A test substance producing neither a dose related increase in the number of revertant colonies nor a reproducible biologically relevant positive response in any of the dose groups is considered to be non-mutagenic in this system.

Validity Criteria
A test is considered acceptable if for each strain:
- the bacteria demonstrate their typical responses to ampicillin (TA 98, TA 100)
- mean values of the the control plates without and with S9 mix are within specified historical control ranges:
- corresponding background growth on both negative control and test plates is observed.
- the positive controls show a distinct enhancement of revertant rates compared with the control plates.

In addition, the properties of the S. typhimurium and E. coli strains with regard to membrane permeability, ampicillin- and tetracycline-resistance as well as
normal spontaneous mutation rates were checked regularly according to Ames et al. 1973. In this way it was ensured that the experimental conditions set up by Ames were fulfilled.

Reference:
Ames BN, Durston WE, Yamasaki E, Lee FD 1973.
Carcinogens are mutagens: a simple test system combining liver homogenates for activation and bacteria for detection.
Proc. Natl. Acad. Sci. (USA) 70, 2281-2285

Statistics:

Statistical analysis of the results attained was not considered to be necessary.

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium, other: TA 98 and TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Remarks:

in all strains and at all concentrations tested

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

In all strains tested at 2500 and/or 5000 µg/plate with and without S9

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Key result

Species / strain:

bacteria, other: S. typhimurium TA 1535, TA 1537, TA 98 and TA 100, E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Remarks:

in all strains and at all concentrations tested

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

In all strains tested at 2500 and/or 5000 µg/plate with and without S9

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 3

Key result

Species / strain:

bacteria, other: S. typhimurium TA 1535, TA 1537, TA 98 and TA 100, E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Remarks:

in all strains and at all concentrations tested

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

In all strains tested at 1000, 2500 and/or 5000 µg/plate with and without S9

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'. Remarks: in Experiment 2 (Pre-incubation Test)

Applicant's summary and conclusion

Conclusions:

Interpretation of results : negative without and with metabolic activation (S9)

In the present study, the test material, octane-1,2-diol, was tested for mutagenicity, both at non-toxic and cytotoxic test material concentrations, in a reverse mutation assay using four different strains of S. typhimurium and one strain of E. coli in the absence and presence of metabolic activation with S9. Mutagenicity of the test material was not evident, as it did not induce any relevant increase in the number of revertant colonies in the five bacteria strains tested. Hence, there was no evidence of point mutations by base pair changes or frameshifts attributable to treatment with the test material.