Dodecane-1,12-diol

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

April 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

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:

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

Deviations:

no

Test guideline 3

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:

Dodecane-1,12-diol

EC Number:

227-133-9

EC Name:

Dodecane-1,12-diol

Cas Number:

5675-51-4

Molecular formula:

C12H26O2

IUPAC Name:

dodecane-1,12-diol

Test material form:

solid

Specific details on test material used for the study:

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature
- Solubility and stability of the test substance in the solvent/vehicle: Stable in DMSO for 24 hours (Envigo Study Number XS21SQ, March 2019)


FORM AS APPLIED IN THE TEST (if different from that of starting material): On the day of the experiment, the test item was dissolved in DMSO.

Method

Target gene:

mutant histidine gene

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:

plate incorporation assay (preexperiment/experiment I):
3, 10, 33, 100, 333, 1000, 2500, 5000 µg/plate with and without S9 mix
preincubation assay (experiment II):
33, 100, 333, 1000, 2500, 5000 µg/plate with and without S9 mix

The test item precipitated in the overlay agar in the test tubes from 100 to 5000 µg/plate in experiment I and from 1000 to 5000 µg/plate in experiment II. Precipitation of the test item in the overlay agar on the incubated agar plates was observed from 1000 to 5000 µg/plate in both experiments. The undissolved particles had no influence on the data recording.
The plates incubated with the test item showed normal background growth up to 5000 µg/plate with and without S9 mix in all strains used.
A single minor toxic effect, evident as a reduction in the number of revertants (below the indication factor of 0.5), occurred in experiment I in strain TA 98 with S9 mix at 5000 µg/plate. No further toxic effects were observed in the remaining test groups.

Vehicle / solvent:

Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: The solvent was chosen because of its solubility properties and its relative nontoxicity to the bacteria.

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

sodium azide

methylmethanesulfonate

other: 4-nitro-o-phenylene-diamine (4-NOPD), 2-aminoanthracene

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation); preincubation

DURATION
- Preincubation period: 60 min
- Exposure duration: 48 hours

NUMBER OF REPLICATIONS: Each concentration, including controls, was tested in triplicate.

DETERMINATION OF TOXICITY
- Method: 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.

Statistics:

According to the OECD guideline 471, a statistical analysis of the data is not mandatory.

Results and discussion

Test results

Test results 1

Species / strain:

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

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:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

with S9 mix at 5000 µg/plate

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

The test item precipitated in the overlay agar in the test tubes from 100 to 5000 µg/plate in experiment I and from 1000 to 5000 µg/plate in experiment II. Precipitation of the test item in the overlay agar on the incubated agar plates was observed from 1000 to 5000 µg/plate in both experiments. The undissolved particles had no influence on the data recording.

Applicant's summary and conclusion

Conclusions:

negative

Executive summary:

The test item was evaluated in an Ames Test on Salmonella typhimurium strains TA 1535, TA 1537, TA 98, TA 100, and the Escherichia coli strain WP2 uvrA, performed according to OECD TG 471. With the exception of S. typhimurium 98 no cytotoxocity was observed up to and including 5000 µg/plate. A single minor toxic effect, evident as a reduction in the number of revertants (below the indication factor of 0.5), occurred in experiment I in strain TA 98 with S9 mix at 5000 µg/plate. The test item precipitated in the overlay agar in the test tubes from 100 to 5000 µg/plate in experiment I and from 1000 to 5000 µg/plate in experiment II. Precipitation of the test item in the overlay agar on the incubated agar plates was observed from 1000 to 5000 µg/plate in both experiments. The undissolved particles had no influence on the data recording.

No substantial increase in revertant colony numbers of any of the five tester strains was observed following treatment with the test item at any dose level, neither in the presence nor absence of metabolic activation (S9 mix). There was also no tendency of higher mutation rates with increasing concentrations in the range below the generally acknowledged border of biological relevance.

Appropriate reference mutagens were used as positive controls and showed a distinct increase of induced revertant colonies.

Therefore, the test item is considered to be non-mutagenic in this Salmonella typhimurium and Escherichia coli reverse mutation assay.