1-ethyl-3-methylimidazol-3-ium;acetate

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

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

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:

1H-imidazolium, 1-ethyl-3-methyl-, acetate

Cas Number:

143314-17-4

Molecular formula:

C6 H11 N2 .C2 H3 02

IUPAC Name:

1H-imidazolium, 1-ethyl-3-methyl-, acetate

Test material form:

liquid

Details on test material:

- Name of test material (as cited in study report): 1-Ethyl-3-methylimidazolium acetate
- Physical state: liquid
- Analytical purity: 95 %
- Lot/batch No.: 08-009; PSN 06/0363-2
- Expiration date of the lot/batch: Stability under storage conditions over test period was guaranteed by the sponsor.
- Storage condition of test material: Room temperature
- Other: color: brown, clear

Method

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:

not applicable

Species / strain 2

Species / strain / cell type:

E. coli WP2 uvr A

Additional strain / cell type characteristics:

not applicable

Metabolic activation:

with and without

Metabolic activation system:

S9-mix

Test concentrations with justification for top dose:

0; 33; 100; 333; 1000; 2750; 5500 µg/plate

Vehicle / solvent:

water

Controls

Controls 1

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 2-aminoanthracene

Remarks:

with S9-mix

Controls 2

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: N-methyl-N'-nitro-N-nitrosoguanidine

Remarks:

without S9-mix

Controls 3

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: 4-nitro-o-phenylenediamine

Remarks:

without S9-mix

Controls 4

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

9-aminoacridine

Remarks:

without S9-mix

Controls 5

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

no

Positive controls:

yes

Positive control substance:

4-nitroquinoline-N-oxide

Remarks:

without S9-mix

Details on test system and experimental conditions:

1st Experiment
Strains: TA 1535, TA 100, TA 1537, TA 98, E. coli WP2 uvrA
Doses: 0; 33; 100; 333; 1 000; 2 750 and 5 500 μg/plate
Type of test: Standard plate test with and without S9 mix
Number of plates: 3 test plates per dose or per control

2nd Experiment
Strains: TA 1535, TA 100, TA 1537, TA 98, E. coli WP2 uvrA
Doses: 0; 33; 100; 333; 1 000; 2 750 and 5 500 μg/plate
Type of test: Preincubation test with and without S9 mix
Number of plates: 3 test plates per dose or per control
Reason: No mutagenicity was observed in the standard plate test.

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 nor precipitates, but tested up to recommended limit concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Test results 2

Species / strain:

E. coli WP2 uvr A

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity nor precipitates, but tested up to recommended limit concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Applicant's summary and conclusion

Conclusions:

1-Ethyl-3-methylimidazolium acetate is not a mutagenic test substance in the bacterial reverse mutation test in the absence and the presence of metabolic activation.

Executive summary:

The test substance 1-Ethyl-3-methylimidazolium acetate was tested for its mutagenic potential based on the ability to induce point mutations in selected loci of several bacterial strains, i.e. Salmonella typhimurium and Escherichia coli, in a reverse mutation assay at concentrations of 0; 33; 100; 333; 1000; 2750 and 5500 µg/plate. The test substance did not lead to a relevant increase in the number of revertant colonies either without S9 mix or after adding a metabolizing system in two experiments carried out independently of each other (standard plate test and preincubation assay). The number of revertant colonies in the negative controls was within or nearby the range of the historical negative control data for each tester strain. In addition, the positive control substances both with and without S9 mix induced a significant increase in the number of revertant colonies within the range of the historical positive control data or above. Thus, it is concluded that 1-Ethyl-3-methylimidazolium acetate is not a mutagenic test substance in the bacterial reverse mutation test in the absence and the presence of metabolic activation.