2-ethylimidazole

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

According to the results of the presently available data, the test substance is not mutagenic in the Ames test under the experimental conditions chosen.

Link to relevant study records

Reference

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:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Restriction: E. coli not tested

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Target gene:

S. typhimurium

Species / strain / cell type:

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

Metabolic activation:

with and without

Metabolic activation system:

Aroclor-induced rat liver S-9 mix

Test concentrations with justification for top dose:

20 ug - 5000 ug/plate

Vehicle / solvent:

water

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Remarks:

with metabolic activation: 2-aminoanthracene; without metabolic activation: N-methyl-N'-nitro-N-nitrosoguanidine, 4-nitro-o-phenylendiamine and 9-aminoacridine chloride monohydrate

Details on test system and experimental conditions:

Standard Plate Test and Preincubation Test

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:

other: No bacteriotoxic effect was observed.

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

No precipitation of the test substance was found.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Table: PreincubationTest (average results of 3 plates, respectively)

Concentration µg/plate	TA 1535*		TA 1535*		TA 1537		TA 98		TA 100
	-S9	+S9	-S9	+S9	-S9	+S9	-S9	+S9	-S9	+S9
Solvent Control	10	11	16	16	7	11	26	43	108	129
20	14	12	23	13	7	5	28	38	108	103
100	12	10	16	17	8	9	26	37	97	99
500	16	13	17	18	8	10	24	37	87	99
2500	11	10	16	14	7	9	26	35	80	96
5000	10	12	20	14	7	10	22	41	80	93
Positive Control	493	50	987	615	163	55	602	545	669	365

*Due to the low spontaneous rate in the 2nd experiment, the preincubation assay using TA 1535 was repeated.

Table: Standard Test (average result of 3 plates, respectively)

Concentration µg/plate	TA 1535		TA 1537		TA 98		TA 100
	-S9	+S9	-S9	+S9	-S9	+S9	-S9	+S9
Solvent Control	18	18	11	9	30	42	105	111
20	19	20	10	9	29	47	103	118
100	17	19	11	10	27	35	103	107
500	18	17	9	9	29	35	96	84
2500	17	18	10	11	31	35	117	94
5000	17	19	9	9	30	33	108	96
Positive Control	1637	105	579	99	1347	628	1164	873

Conclusions:

Interpretation of results: negative
According to the results of the present study, the test substance 2-Ethylimidazol is not mutagenic in the Ames test under the experimental conditions chosen here.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (negative)

Additional information

In a reverse gene mutation assay in bacteria (Ames-test), strains TA 1535, TA 100, TA 1537 and TA 98 of S. typhimurium were exposed to the test substance at concentrations of 20, 100, 500, 2500 and 5000 µg/plate (BASF AG, 1993). Standard plate test and preincubation test both were conducted with and without metabolic activation (Aroclor induced rat liver S-9 mix). The positive controls induced the appropriate responses in the corresponding strains. There was no evidence of induced mutant colonies over background.According to the results of the present study, the test substance is not mutagenic in the Ames test under the experimental conditions chosen here.

Justification for classification or non-classification

The available experimental test data are reliable and suitable for classification purposes under Regulation (EC) No 1272/2008. As a result based on this Ames test the substance is not considered to be classified for genetic toxicity under Regulation (EC) No 1272/2008.