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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Type of information:
experimental study
Remarks:
used to justify read-across for other endpoints
Adequacy of study:
supporting study
Study period:
1994-12-20 to 1995-01-13
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1995
Report Date:
1995

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Version / remarks:
revised draft document of May 1994
Deviations:
no
Qualifier:
according to
Guideline:
EU Method B.13/14 (Mutagenicity - Reverse Mutation Test Using Bacteria)
Version / remarks:
31 July 1992
Deviations:
no
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
other: liquid
Details on test material:
- Name of test material (as cited in study report): 2-ethoxyethyl methacrylate, MAEE

Method

Target gene:
his
Species / strain
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102
Metabolic activation:
with and without
Metabolic activation system:
S9 mix
Test concentrations with justification for top dose:
preliminary toxicity test: 0, 10, 100, 500, 1000, 2500 and 5000 µg/plate
mutagenicity tests: 0, 312.5, 625, 1250, 2500 and 5000 µg/plate
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: solubility
Controlsopen allclose all
Negative solvent / vehicle controls:
yes
Positive controls:
yes
Positive control substance:
9-aminoacridine
2-nitrofluorene
sodium azide
mitomycin C
Remarks:
without metabolic activation
Positive controls:
yes
Positive control substance:
other: 2-anthramine, Danthron
Remarks:
with metabolic activation
Details on test system and experimental conditions:
METHOD OF APPLICATION: in agar (plate incorporation); second test with metabolic activation: preincubation

DURATION
- Preincubation period: 60 min (second test with metabolic activation)
- Exposure duration: 48-72 h

NUMBER OF REPLICATIONS: 3

DETERMINATION OF CYTOTOXICITY
- Method: background bacterial lawn
Evaluation criteria:
The following criteria were used as an aid for determining a positive response:
- a reproducible and significant dose relationship
and/or
- a reproducible and significant increase (i.e. a doubling in the number of revertants for at least one of the tested strains when compared to that of the controls) for at least one of the doses

A test substance is considered as non-mutagenic in this test system if the above two criteria are not fully met.
Biological and statistical significances were considered during the evaluation.

Results and discussion

Test results
Species / strain:
S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Vehicle controls validity:
valid
Positive controls validity:
valid
Additional information on results:
TEST-SPECIFIC CONFOUNDING FACTORS
- Precipitation: no

COMPARISON WITH HISTORICAL CONTROL DATA:
controls were within historical range

ADDITIONAL INFORMATION ON CYTOTOXICITY:
cytotoxicity was observed in strain TA100 at concentrations of 1250 µg/plate and higher without metabolic activation and in strain TA1537 at a concentration of 5000 µg/plate without metabolic activation, but only in one experiment; in the preincubation test cytotoxicity was
observed in strains TA1535 and TA100 at a concentration of 5000 μg/plate with metabolic activation;
no cytotoxicity observed up to limit dose in all other strains
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:
ETMA did not induce mutant colonies over background. ETMA was tested up to limit concentrations of 5000 µg/plate.
Executive summary:

In a reverse gene mutation assay in bacteria according to OECD guideline 471, revised draft document of May 1994, S. typhimurium TA 1535, TA 1537, TA 98, TA 100 and TA 102 strains were exposed to ETMA (99.94% a.i.) in DMSO at concentrations of 0, 312.5, 625, 1250, 2500 and 5000 µg/plate in the presence and absence of mammalian metabolic activation. The test was performed as plate incorporation assay; the second experiment with metabolic activation was performed as pre-incubation test with 60 minutes pre-incubation. ETMA was tested up to limit concentrations (5000 µg/plate).

Cytotoxicity was observed in strain TA100 at concentrations of 1250 µg/plate and higher without metabolic activation and in strain TA1537 at a concentration of 5000 µg/plate without metabolic activation, but only in one experiment. In the preincubation test cytotoxicity was observed in strains TA1535 and TA100 at a concentration of 5000 µg/plate with metabolic activation. No cytotoxicity observed up to limit dose in all other strains. The positive controls induced the appropriate responses in the corresponding strains. 

There was no evidence of induced mutant colonies over background.