Cyclopentane, methoxy-

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Remarks:

Type of genotoxicity: gene mutation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

18 June 2001 - 02 July 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study was performed in accordance with several official test guidelines including OCED, EC and US EPA, and in compliance with GLP; on this basis the study is considered reliable without restriction.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

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:

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

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Test guideline 4

Qualifier:

according to guideline

Guideline:

JAPAN: Guidelines for Screening Mutagenicity Testing Of Chemicals

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:

-

EC Number:

445-090-6

EC Name:

-

Cas Number:

5614-37-9

Molecular formula:

C6 H12 O

IUPAC Name:

Cyclopentyl methyl ether

Test material form:

liquid

Specific details on test material used for the study:

- Analytical purity: 99.6%
- Lot/batch No.: 01529

Method

Species / strain

Species / strain 1

Species / strain / cell type:

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

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A pKM 101

Metabolic activation:

with and without

Metabolic activation system:

Liver homogenate derived from Aroclor 1254-induced rats (S-9 mix).

Test concentrations with justification for top dose:

Range-finding study: 5, 15, 50, 150, 500, 1500, and 5000 µg/plate (with and without metabolic activation)
Definitive study: 50, 150, 500, 1500, and 5000 µg/plate (with and without metabolic activation).

Vehicle / solvent:

Solvent: Dimethylsulfoxide (DMSO)
Solubility of the test material was assesed in both DMSO and water; the test substance was found to be insoluble in water, but soluble in DMSO. For this reason, DMSO was selected as the solvent.

Controls

Controls 1

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

sodium azide

Remarks:

Positive control for TA1535 and TA100 in the absence of S9 mix

Controls 2

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

9-aminoacridine

Remarks:

Positive control for TA1537 in the absence of S9 mix

Controls 3

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

2-nitrofluorene

Remarks:

Positive control for TA98 in the absence of S9 mix

Controls 4

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

other: 2-(2-Furyl)-3-(5-nitro-2-furyl)acrylamide

Remarks:

Positive control for WP2uvrA/pKM101 in the absence of S9 mix

Controls 5

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene

Remarks:

Positive control for TA1535 and WP2uvrA/pKM101 in the presence of S9 mix

Controls 6

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

benzo(a)pyrene

Remarks:

Positive control for TA1537, TA98 and TA100 in the presence of S9 mix

Details on test system and experimental conditions:

METHOD OF APPLICATION:in agar (plate incorporation)

DURATION
- Preincubation period: 30 minutes (main test only)
- Exposure duration: 72 hours

NUMBER OF REPLICATIONS: 3 Plates per concentration

DETERMINATION OF CYTOTOXICITY
- Method: relative total growth (appearance of background bacterial lawn)

Evaluation criteria:

Number of revertant colonies, relative to concurrent vehicle controls. A two-fold increase in the number of revertant colonies relative to the concurrent control group, with some evidence of a dose-relationship is considered significant.

Results and discussion

Test results

Test results 1

Species / strain:

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

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

E. coli WP2 uvr A pKM 101

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Additional information on results:

Observations:
No signs of toxicity were observed towards the tester
strains in either mutation test.


The first (range-finding) test was a standard plate
incorporation assay; the second involved a pre-incubation
stage.

Applicant's summary and conclusion

Conclusions:

Under the conditions of this bacterial reverse mutation assay, the substance showed no evidence of mutagenic activity in any of the strains tested, either in the presence or absence of metabolic activation.