4-methylmorpholine

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:

1990-06-25 - 1990-06-29

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Materials and methods

Test guideline

Qualifier:

equivalent or similar 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:

4-methylmorpholine

EC Number:

203-640-0

EC Name:

4-methylmorpholine

Cas Number:

109-02-4

Molecular formula:

C5H11NO

IUPAC Name:

4-methylmorpholine

Test material form:

liquid

Specific details on test material used for the study:

- Name of test material (as cited in study report): 6398-24-20
- Lot No.: Project #90-005
- Substance type: Clear colorless liquid
- Physical state: Liquid
- Purity: responsibility of the sponsor
- Stability under test conditions: There was no apparent change in the physical state of the test article during the assay.
- Storage condition of test material: For the purposes of this study, the test article was stored at room temperature in the container received from the sponsor.

Method

Target gene:

histidine locus

Species / strain

Species / strain 1

Species / strain / cell type:

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

Additional strain / cell type characteristics:

other: uvrB deletion mutation and a rfa mutation

Species / strain 2

Species / strain / cell type:

S. typhimurium TA 1538

Additional strain / cell type characteristics:

other: uvrB deletion mutation and a rfa mutation

Metabolic activation:

with and without

Metabolic activation system:

aroclor 1254-induced male Sprague-Dawley rat liver homogenate

Test concentrations with justification for top dose:

preliminary toxicity prescreen: 50, 167, 500, 1670 and 5000 ug/plate in absence of S9
mutation assay: 167, 500, 1670, 5000, 7500 and 10000 ug/plate in the presence and absence of S9

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO

Controls

Controls 1

Untreated negative controls:

yes

Remarks:

solvent control

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Remarks:

solvent or test substance without tester strains

Positive controls:

yes

Positive control substance:

sodium azide

Remarks:

in the absence of metabolic activation 10.0 ug/plate for TA1535 and TA100

Controls 2

Untreated negative controls:

yes

Remarks:

solvent control

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Remarks:

solvent or test substance without tester strains

Positive controls:

yes

Positive control substance:

9-aminoacridine

Remarks:

in the absence of metabolic activation 150 ug/plate for TA1537

Controls 3

Untreated negative controls:

yes

Remarks:

solvent control

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Remarks:

solvent or test substance without tester strains

Positive controls:

yes

Positive control substance:

2-nitrofluorene

Remarks:

in the absence of metabolic activation 5.00 ug/plate for TA1538 and TA98

Controls 4

Untreated negative controls:

yes

Remarks:

solvent control

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Remarks:

solvent or test substance without tester strains

Positive controls:

yes

Positive control substance:

other: 2-anthramine, 2.50 ug/plate for all 5 tester strains

Remarks:

with metabolic activation

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation)

DURATION
- Exposure duration: 48 hours

NUMBER OF REPLICATIONS: triplicate

Evaluation criteria:

A positive result is defined as a statistically significant, dose-dependent increase in the number of histidine-independent revertants with at least one dose level inducing a revertant frequency that is two-fold the spontaneous solvent control value. If the test article does not induce a statistically significant, dose-dependent increase in revertant frequency but does induce a revertant frequency at one dose level that is two-fold the spontaneous control value, the results is considered equivocal. A negative result is defined as the absence of a statistical significant or dose-dependent increase in the number of histidine-independent revertants.

Results and discussion

Test results

Test results 1

Key result

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

Remarks:

evaluated in toxicity prescreen by treating duplicate cultures of strain TA100 in absence of S9; the substance was not toxic up to 5000 ug/plate

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Key result

Species / strain:

S. typhimurium TA 1538

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Remarks:

evaluated in toxicity prescreen by treating duplicate cultures of strain TA1538 in absence of S9; the substance was not toxic up to 5000 ug/plate

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Conclusions:

The test substance demonstrated to be negative in the Ames/Salmonella Plate Incorporation Assay under the conditions of the test, and according to the criteria of the protocol. The substance is considered not to be classified as mutagenic according to the CLP Regulation.