1,2-dichloroethane

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1985

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, 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

Test material information

Constituent 1

Reference substance name:

1,2-dichloroethane

EC Number:

203-458-1

EC Name:

1,2-dichloroethane

Cas Number:

107-06-2

Molecular formula:

C2H4Cl2

IUPAC Name:

1,2-dichloroethane

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 / strain

Species / strain 1

Species / strain / cell type:

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

Species / strain 2

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

Controls

Controls 1

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

Controls 2

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

Controls 3

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

Controls 4

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

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