6-ethyl-2-toluidine

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:

other: GLP and guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

GLP compliance:

yes

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

6-ethyl-2-toluidine

EC Number:

246-309-6

EC Name:

6-ethyl-2-toluidine

Cas Number:

24549-06-2

Molecular formula:

C9H13N1

IUPAC Name:

2-ethyl-6-methylaniline

Details on test material:

2-methyl-6-ethylanilin purity: 99.9 %

Method

Target gene:

ames assay

Species / strain

Species / strain / cell type:

S. typhimurium, other: tester strains TA 1535, TA 100, TA 1537, TA 98, TA 102

Metabolic activation:

with and without

Metabolic activation system:

S9-mix, S9 from male Sprague Dawley rats (liver enzyme induction by single intraperitonial injection of Aroclor 1254

Test concentrations with justification for top dose:

0, 50, 158, 500, 1581, 5000 µg/plate

Controls

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

True negative controls:

yes

Positive controls:

yes

Positive control substance:

other: -S9: sodium azide, nitrofurantoin, 4-nitro-1,2-phenylene diamine, mitomycin C, cumene hydroperoxide, +S9: 2-aminoanthracene

Results and discussion

Test results

Species / strain:

S. typhimurium, other: tester strains TA 1535, TA 100, TA 1537, TA 98, TA 102

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'. Remarks: tester strains TA 1535, TA 100, TA 1537, TA 98, TA 102

Any other information on results incl. tables

Doses up to and including 500 µg per plate did not cause any bacteriotoxic effects. Total bacteria counts remained unchanged and no inhibition of growth was observed. At higher doses, the substance had a strong, strain-specific bacteriotoxic effect, so that this range could only partly be used up to and including 5000 µg per plate for assessment purposes.

Evidence of mutagenic activity of 2 Methyl-6-ethylanilin was not seen. No biologically relevant increase in the mutant count, in comparison with the negative controls, was observed.

The positive controls sodium azide, nitrofurantoin, 4-nitro-1,2-phenylene diamine, mitomycin C, cumene hydroperoxide and 2-aminoanthracene had a marked muta-genic effect, as was seen by a biologically relevant increase in mutant colonies com-pared to the corresponding negative controls.

Therefore, 2 Methyl-6-ethylanilin was considered to be non-mutagenic without and with S9 mix in the plate incorporation as well as in the preincubation modification of the Salmonella/microsome test.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative

Executive summary:

The mutagenic potential in bacteria of the test substance 2-ethyl-6-methylaniline (MEA) was evaluated in a GLP and OECD guideline study (TG 471). Here, the tester strains Salmonella typhimurium TA 98, TA 100, TA 1535, TA 1537 and TA 102 were used. Treatments by the plate incorporation method and the pre-incubation method were done for doses up to 5000 µg/ plate. The tester strains were evaluated with and without metabolic activation. No toxic effects of MEA were noted up to 500 µg/plate; whereas higher doses had a strong, strain-specific toxic effect. In this study no biologically relevant and dose dependent increases in revertants was observed in any of the tester strains evaluated with and without metabolic activation. Therefore, 2 Methyl-6-ethylanilin was considered to be non-mutagenic without and with S9 mix in the plate incorporation as well as in the preincubation modification of the Salmonella/microsome test (Lanxess Deutschland GmbH 2009).