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Toxicological information

Genetic toxicity: in vitro

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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
Study period:
1985
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Meets generally accepted scientific standards, well-documented and acceptable for assessment.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1985
Report Date:
1985

Materials and methods

Principles of method if other than guideline:
The test substance was tested in the strains TA 1535, TA 100, TA 1537 and TA 98 in a standard plate test or in the strains TA 1535 and TA 100 in a modified exsiccator test for it's mutagenic potential.
GLP compliance:
no
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
gas under pressure: refrigerated liquefied gas
Details on test material:
- Name of test material (as cited in study report): 1,2-Dichlorethane
- Storage condition of test material: refrigerator ( 4 °C)
no further data

Method

Species / strainopen allclose all
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Species / strain / cell type:
other: S. typhimurium TA 1535 and TA 100 (exsiccator test)
Metabolic activation:
with and without
Metabolic activation system:
S-9 mix
Test concentrations with justification for top dose:
20 - 5000 µg/plate standard plate test, 3000 and 6000 µl/30 l in an exsiccator (modified test)
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: [DMSO]
- Justification for choice of solvent/vehicle: The test substance was completely soluble in DMSO
Controlsopen allclose all
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
not specified
Positive controls:
yes
Positive control substance:
other: 2-aminoanthracene
Remarks:
with S-9 mix for strains TA 100, TA 98, TA 1535 and TA 1537
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
not specified
Positive controls:
yes
Positive control substance:
other: N-Methyl-N'-nitro-N-nitroso-guanidine
Remarks:
without S-9 mix for strain TA 100 and TA 1535
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
not specified
Positive controls:
yes
Positive control substance:
other: 4-Nitro-o-phenylendiamine
Remarks:
without S-9 mix for strain TA 98
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
not specified
Positive controls:
yes
Positive control substance:
other: 9-aminoacridine chloride
Remarks:
without S-9 mix for stain TA 1537
Details on test system and experimental conditions:
METHOD OF APPLICATION: in agar (plate incorporation) and in a modified exsiccator test


DURATION
- Exposure duration: ca. 48 hours at 37 °C (plate incorporation); 4 hours at 37°C in the exsiccator and then 44 hours at 37°C


DETERMINATION OF CYTOTOXICITY
- Method: relative total growth
Evaluation criteria:
In general, a substance to be characterized as positive in the Ames test has to fulfill the following requirements:
- doubling of the spontaneous mutation rate (control)
- dose-response relationship
- reproducibility of the results.
Statistics:
no data

Results and discussion

Test results
Species / strain:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Metabolic activation:
with and without
Genotoxicity:
positive
Cytotoxicity / choice of top concentrations:
no 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'.

Any other information on results incl. tables

Standard plate test

Without S-9 mix: a slight increase of the mutation rate with TA 1535 at 2500 and 5000 µg (factor 1.7); no increase was observed with TA 100, TA 1537 and TA 98.

 

With S-9 mix: a slight increase of the mutation rate with TA 1535 in a dose dependent manner reaching factor 2 at a dose of 5000 µg; no increase was observed with TA 100, TA 1537 and TA 98.

 

Modified exsiccator test:

Without S-9 mix: an increase of factor 1.7 to 4.7 with TA 1535 (3000 µl/30 l exsiccator), increase of factor 4.3 to 5.3 with TA 1535 (6000 µl/30 l exsiccator), only slight increase (factor 1.7) with TA 100 in 1/2 experiments (6000 µl/30 l exsiccator).

 

With S-9 mix (without glutathione): an increase of factor 6.1 to 8.9 with TA 1535 (3000 µl/30 l exsiccator), increase of factor 5.8 to 10.0 with TA 1535 (6000 µl/30 l exsiccator), only slight increase (factor 2.2) with TA 100 in 1 out of 2 experiments (3000 µl/30 l exsiccator), only slight increase (factor 1.8 -2.3) with TA 100 (6000 µl/30 l exsiccator) with S-9 mix (supplemented with glutathione): mutagenic with TA 1535 at both concentrations (factor 30.5 -41.2), increase of factor 2.0 to 4.9 with TA 100 depending on the amount of test substance.

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
positive