Linalyl formate

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: GLP and test guideline compliant study.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes (incl. QA statement)

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Linalyl formate

EC Number:

204-120-6

EC Name:

Linalyl formate

Cas Number:

115-99-1

Molecular formula:

C11H18O2

IUPAC Name:

linalyl formate

impurity 1

Reference substance name:

Linalyl acetate

EC Number:

204-116-4

EC Name:

Linalyl acetate

Cas Number:

115-95-7

Molecular formula:

C12H20O2

IUPAC Name:

1,5-dimethyl-1-vinylhex-4-en-1-yl acetate

impurity 2

Reference substance name:

Linalool

EC Number:

201-134-4

EC Name:

Linalool

Cas Number:

78-70-6

Molecular formula:

C10H18O

IUPAC Name:

3,7-dimethylocta-1,6-dien-3-ol

Test material form:

liquid

Details on test material:

Identification: Linalyl Formate
Molecular formula: C11H18O2
Molecular weight: 182.2 g/mol
CAS No.: 115-99-1
Description: colourless liquid
Storage: at room temperature in the dark

Method

Target gene:

Histidine

Species / strain

Species / strain / cell type:

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

Additional strain / cell type characteristics:

not applicable

Metabolic activation:

with and without

Metabolic activation system:

S9 fraction

Test concentrations with justification for top dose:

Dose range finding test: 3, 10, 33, 100, 333, 1000, 3330 and 5000 μg/plate in the absence and presence of S9 mix in the direct plate assay.

Preincubation assay:
without S9 mix: 1, 3, 10, 33, 100 and 333 μg/plate
with S9 mix: 3, 10, 33, 100, 333 and 1000 μg/plate

Direct plate assay 1: tested up to the dose level of 5000 μg/plate

Direct plate assage 2: tested up to the dose level of 3330 μg/plate

Vehicle / solvent:

The test substance was dissolved in dimethyl sulfoxide of spectroscopic quality (Merck). Test substance concentrations were prepared directly prior to use and used within 4 hours after preparation.

Controls

Controls 1

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

2-nitrofluorene

sodium azide

cumene hydroperoxide

methylmethanesulfonate

other: Daunomycin

Remarks:

without S9 mix

Controls 2

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

no

Positive control substance:

other: 2-aminoanthracene; 1,8-dihydroxy anthraquinone

Remarks:

with S9 mix

Details on test system and experimental conditions:

Salmonella typhimurium bacteria
Source: Dr. Bruce N. Ames, University of Califormia at Berkeley, USA
The Salmonella typhimurium strains were checked regularly to confirm their histidine-requirement, crystal violet sensitivity, ampicillin resistance (TA98, TA100 and TA 102), tetracycline resistance (TA 102), UV sensitivity and the nuber of spontaneous revertants.
Stock cultures of the five strains were stored in liquid nitrogen (-196 °C)

Evaluation criteria:

A test substance is considered negative (not mutagenic) in the test if:
a) The total number of revertants in any tester strain at any concentration is not greater than two times the solvent controol value, with or without metabolic activation.
b) The negative responsive should be repoducible in at least one repeated experiment.

A test substance is considered positive (mutagenic) in the test if:
a) It induces at least a 2-fold, dose related increase in the number of revertants with respect to the number induced by the solvent control in any of the tester strains, wither with or without metabolic activation.
However, any mean plate count or less than 20 is considered to be not significant.
b) The positive response should be reproducible on at least one repeated experiment.

The preceding criteria were not absolute and other modifying factors might enter into the final evaluation decision.

Statistics:

no data

Results and discussion

Test results

Test results 1

Species / strain:

S. typhimurium, other: TA1535, TA1537, TA98 and TA102

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 2

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with

Genotoxicity:

other: Linalyl formate showed mutagenic potential at cyctoxic concentrations

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:

Based on the results of this study, it is concluded that Linalyl formate showed mutagenic potential in strain TA100 at cytotoxic concentrations in the Salmonella typhimurium reverse mutation assay (direct plate assay). No mutagenicity was seen in other strains, in TA 100 at non-cytotoxic concentrations and in the preincubation assay.