N-acetylhexanelactam

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:

1998-10-27 to 1998-11-21

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study is performed according to guideline. Only four S. typhimurium strains were tested as required at the time of testing. Acceptable, well documented study report which meets basic scientific principles.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1998

Report date:

1998

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

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:

1888-91-0

IUPAC Name:

1888-91-0

Constituent 2

Reference substance name:

N-acetylhexanelactam

EC Number:

217-565-6

EC Name:

N-acetylhexanelactam

Cas Number:

1888-91-1

Molecular formula:

C8H13NO2

IUPAC Name:

1-acetylazepan-2-one

Test material form:

other: liquid, clear yellowish

Details on test material:

- Name of test material: Acetylcaprolactam
- Physical state: liquid
- Analytical purity: not specified
- Lot/batch No.: Op.2
- Expiration date of the lot/batch: July 1999
- Storage condition of test material: at room temperature protected from light and moisture

Method

Species / strain

Species / strain / cell type:

bacteria, other: S. typhimurium TA 97a, TA 98, TA 100, TA 1535

Metabolic activation:

with and without

Metabolic activation system:

liver homogenate from phenobarbital (i.p.) and ß-naphthoflavone(oaral) induced rats (S9)

Test concentrations with justification for top dose:

Experiment 1.: 0.005, 0.05 and 0.5 (mg/plate)
Experiment 2.: 0.05, 0.16, 0.5, 1.6 and 5.0 (mg/plate)

Vehicle / solvent:

bidistilled water

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Positive controls:

yes

Positive control substance:

sodium azide

other: 2-amino-anthracene, nitrofurantoine; 4-nitro-1, 2-phenylene-diamine; ICR 191;

Details on test system and experimental conditions:

Three replicates per concentration level and control. Duration of incubation time of each experiment was 48 hours. The first study was conducted with 3 concentration levels of the test substance (0.005 - 0.5 mg/plate). Based on the results of the first experiment the second experiment was performed with 5 concentration levels (0.05-5.0 mg/plate) with and without metabolic activation.

Evaluation criteria:

Since the reduced background lawn is regarded to be a cytotoxic effect, plates with reduced background lawn were not included into evaluation processes.

Statistics:

Arthmetic mean values and standard deviations were calculated out of colonies per plate of three replicates. For evaluation of the results the induction rate the mean values were calculated:
Induction rate = revertant colonies of test substance divided by revertant colonies of the corresponding control.
The test substance is to interpret mutagenic if there is a concentration effect relationship and the induction rate is ≥ 2.
Calculations were performed using software Excel 5.0, Microsoft corporation.

Results and discussion

Test results

Test results 1

Key result

Species / strain:

S. typhimurium 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

Key result

Species / strain:

other: S. typhimurium TA 97a

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

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

Vehicle controls validity:

valid

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:

no cytotoxicity

Vehicle controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative with and without metabolic activation system

Based on the results of this test the test substance is regarded to be not mutagenic.

Executive summary:

In this study (Ames test) Acetylcaprolactam was found to have no mutagenic effects onSalmonella typhimuriumstrains TA 97a, TA 98, TA 100 and TA 1535 with and without metabolic activation system at concentrations of 0.005 - 5.0 mg/plate. No cytotoxic effects were observed at these dose levels.