3-(dodecylthio)butyronitrile

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:

03 May 2001 to 07 May 2001

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study was not conducted under GLP conditions.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

yes

Remarks:

The study was performed with the strains TA 98 and TA 100 only

GLP compliance:

no

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Laurylmercaptobytyronitril

IUPAC Name:

Laurylmercaptobytyronitril

Details on test material:

- Name of test material (as cited in study report): Laurylmercaptobytyronitril
- Substance type: Mono-constituent
- Physical state: Liquid
- Analytical purity: 99%
- Purity test date:
- Lot/batch No.: P 5889001
- Expiration date of the lot/batch: 01 April, 2002
- Storage condition of test material: At room temperature

Method

Target gene:

Histidine operon

Species / strain

Species / strain / cell type:

other: S. typhimurium TA 98 and TA 100

Metabolic activation:

with and without

Metabolic activation system:

S9 rat liver microsomal fraction

Test concentrations with justification for top dose:

3, 10, 33, 100, 333, 1000, 2500, and 5000 ug/plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: Ethanol
- Justification for choice of solvent/vehicle: Solubility properties and its relative non-toxicity to the bacteria.

Controls

Controls 1

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

Ethanol

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene

Remarks:

This positive control was utilized in S. typhimurium strains TA 98 and TA 100 with metabolic activation.

Controls 2

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

Ethanol

True negative controls:

no

Positive controls:

yes

Positive control substance:

sodium azide

Remarks:

This positive control was utilized in S. typhimurium strain TA 100 without metabolic activation.

Controls 3

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

Ethanol

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 4-nitro-o-phenylene-diamine, 4-NOPD

Remarks:

This positive control was utilized in S. typhimurium strain TA 98 without metabolic activation.

Details on test system and experimental conditions:

METHOD OF APPLICATION: in medium

DURATION
- Preincubation period: 4 hours
- Exposure duration: 48 hours
- Expression time (cells in growth medium): 52 hours
- Selection time (if incubation with a selection agent): 48 hours
- Fixation time (start of exposure up to fixation or harvest of cells): 48 hours

SELECTION AGENT (mutation assays): L-Histidine

NUMBER OF CELLS EVALUATED: All plates were evaluated for an increase in revertant colonies.

Evaluation criteria:

A test item is considered positive if a dose related increase in the number of revertants or a biologically relevant increase for at least one test concentration is induced.

Results and discussion

Test results

Species / strain:

other: S. typhimurium

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Effects of pH: None
- Effects of osmolality: None
- Evaporation from medium: None
- Precipitation: No precipitation was observed at any dose.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

Based on the results of the study, the test article is not mutagenic in a screening Ames Assay.

Executive summary:

The mutagenic potential of the test article was evaluated in a screening Bacterial Reverse Mutation Assay with S. typhimurium strains TA 98 and TA 100 in the presence and absence of a metabolic activation system (S9 mix). The study was not performed in compliance with GLP regulations. The test method was based on OECD 471 (1997) but only S. typhimurium strains TA 98 and TA 100 were utilized. The test article was dissolved in ethanol for dosing at 3, 10, 33, 100, 333, 1000, 2500, and 5000 ug/plate and all strains were tested in triplicate. Separate experiments were performed in the presence and absence of metabolic activation with S9 mix. Strain specific positive controls and vehicle controls were tested in parallel. No toxic effects were seen in the study. No reduction in the number of colonies occurred in the presence or absence of metabolic activation. No increase in the number of revertant colonies was seen in any strain in the presence or absence of metabolic activation. Controls performed as expected. Based on the results of the study, the test article is not mutagenic in the screening Ames Assay in the presence or absence of metabolic activation.