3,7-dimethylocta-2,6-dienyl acetate

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:

31 May 2000 - 28 July 2000

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

This information is used for read-across to Neryl acetate multi

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2000

Report date:

2000

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Version / remarks:

21 July 1997

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:

Neryl acetate

EC Number:

205-459-2

EC Name:

Neryl acetate

Cas Number:

141-12-8

Molecular formula:

C12H20O2

IUPAC Name:

(2Z)-3,7-dimethylocta-2,6-dien-1-yl acetate

Method

Target gene:

- S. typhimurium: Histidine gene

Species / strain

Species / strain / cell type:

S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102

Metabolic activation:

with and without

Metabolic activation system:

Rat liver S9-mix from rats that had been induced with Aroclor 1254 (500 mg/kg body weight).

Test concentrations with justification for top dose:

Experiment 1 (Strains TA1535, TA1537, TA98, TA100, and TA102).
(without S9) All tester strains: 5, 15, 50, 150, 500, 1500 µg/plate
(with S9) All tester strains: 5, 15,50, 150, 500, 1500, 5000 µg/plate

Experiment 2 (Strains TA1535, TA1537, TA98, TA100, and TA102).
(without S9) All tester strains: 5, 15, 50, 150, 500, 1500 µg/plate
(with S9) All tester strains: 5, 15,50, 150, 500, 1500, 5000 µg/plate

Vehicle / solvent:

- Vehicle used: DMSO
- Justification for vehicle: the vehicle is according to OECD guideline 471

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

2-nitrofluorene

sodium azide

mitomycin C

other: 2-Aminoanthracene (2-AA)

Remarks:

For more details on positive controls, see 'additional details on methods'

Details on test system and experimental conditions:

Two individual experiments were performed. The first experiment was a direct plate assay and included a dose-range finding test, the second experiment was a pre-incubation assay.

METHOD OF APPLICATION: To each culture tube containing 2 ml of top agar 0.1 mL of bacteria was added followed by the test solution and 0.5 ml of S9-mix or phosphate buffer in the assays without metabolic activation. The test components were mixed thoroughly with a vortex and immediately poured onto coded minimal agar plates and carefully spread to achieve an uniform distribution of the top agar on the surface of the plate. The minimal agar plates contain 20 to 25 mL of 1.5 % agar in Vogel-Bonner medium E with 2 % glucose. Three parallel plates were prepared for each experimental point. Plates were kept for 48 to 72 h at 37°C in the dark and then examined. Besides the counting of the number of revertant colonies, the plates were examined for the existence of a normal background lawn and/or precipitates and
microscopically for microcolony growth.

DURATION
- Exposure duration: 48 - 72 hour

NUMBER OF REPLICATIONS:
- Doses of the test substance were tested in triplicate in each strain.

NUMBER OF CELLS EVALUATED: >1E8 per plate

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

from 1500 (μg/plate) , without S9 and from 5000 (μg/plate) with S9

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 2

Key result

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

upwards from 1500 (μg/plate) , without and with S9

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 3

Key result

Species / strain:

S. typhimurium TA 102

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

upwards from 1500 (μg/plate) , without and with S9

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 4

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

upwards from 500 (μg/plate) without and with S9

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 5

Key result

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

from 1500 (μg/plate) , without S9 and from 5000 (μg/plate) with S9

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Additional information on results:

No precipititation occurred.

Historical control data: The controls were close to the laboratory historical control data range.

Applicant's summary and conclusion

Conclusions:

In an Ames test, performed according to OECD guideline 471 and GLP principles, Nerylacetate was found not to be mutagenic in the Salmonella typhimurium strains TA1535, TA1537, TA98, TA100,
and TA102, in the absence and in the presence of metabolic activation.

Executive summary:

The mutagenic activity of Neryl Acetate (‘mono’) was evaluated in a study according to OECD TG 471 and in compliance with GLP criteria. The test was performed in two independent experiments. The substance was dissolved in DMSO and tested in concentrations of 5 to 1500 μg/plate in the absence and of 5 to 5000 μg/plate in the presence of S9. In the absence of S9-mix the substance was bacteriotoxic towards the strain TA1535 at 500 μg/plate and towards the strains TA98, TA100, TA102, and TA1537 at 1500 μg/plate. In the presence of S9-mix the substance was bacteriotoxic towards the strain TA1535 at 500 μg/plate, towards the strains TA100 and TA102 at 1500 μg/plate and towards the strains TA98 and TA1537 at 5000 μg/plate. Precipitation of the test compound in the plates was not observed. Adequate negative and positive controls were included.

The substance did not induce a significant dose-related increase in the number of revertant (His+) colonies in each of the five S. typhimurium tester strains (TA1535, TA1537, TA98, TA100 and TA102), both in the absence and presence of S9-metabolic activation. These results were confirmed in independently repeated experiments. Based on the results of this study it is concluded that the substance is not mutagenic in the Salmonella typhimurium reverse mutation assay.