Undecanolactone

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:

14 April 2016 - 25 April 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2016

Report date:

2016

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Undecanolactone

EC Number:

254-399-3

EC Name:

Undecanolactone

Cas Number:

39282-36-5

Molecular formula:

C11H20O2

IUPAC Name:

(5E,13E)-icosa-5,13-dienoic acid; 6-tetradecyloxan-2-one

Method

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:

Liver preparations (S9 mix) from rats treated with phenobarbital and 5,6-benzoflavone.

Test concentrations with justification for top dose:

Up tto 5000 μg/plate. This is the standard limit concentration recommended in the regulatory guidelines that this assay follows. Other concentrations used were a series of ca half-log10 dilutions of the highest concentration.
In the first test, toxicity concentrations of 150, 500 and 1500 μg/plate in strain TA100 in the absence of S9 mix and at 1500 μg/plate in strain TA100 and 5000 μg/plate in strain TA1537 in the presence of S9 mix.
In the second test concentrations of 5, 15 and 50 μg/plate in strain TA100 in the absence of S9 mix and at 5000 μg/plate in strain TA1537 in the absence and presence of S9 mix.

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

sodium azide

Evaluation criteria:

If exposure to a test item produces a reproducible increase in mean revertant colony numbers of at least twice (three times in the case of strains TA1535 and TA1537) that of the concurrent vehicle controls, with some evidence of a positive concentration-response relationship, it is considered to exhibit mutagenic activity in this test system.

Results and discussion

Test results

Test results 1

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 2

Key result

Species / strain:

S. typhimurium TA 1537

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 3

Key result

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 4

Key result

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Test results 5

Key result

Species / strain:

E. coli WP2 uvr A pKM 101

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

not applicable

Positive controls validity:

valid

Applicant's summary and conclusion

Conclusions:

It was concluded that the substance showed no evidence of mutagenic activity in these bacterial systems under the test conditions employed.

Executive summary:

In the in vitro genotoxicity study (Ames test) the substance was tested for mutagenicity in Salmonella typhimurium strains TA1535, TA1537, TA98 and TA100, and in Escherichia coli strain WP2 uvrA (pKM101). Concentrations of up to 5000 μg/plate were tested. No evidence of mutagenic activity was seen at any concentration of the substance in either mutation test. It was concluded that the substance showed no evidence of mutagenic activity in these bacterial systems under the test conditions employed.