Registration Dossier

Toxicological information

Genetic toxicity: in vitro

Currently viewing:

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:
no data
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: The study was performed according to JETOC protocols similar to OECD471. Data from the JETOC is generally well trusted.

Data source

Reference
Reference Type:
publication
Title:
Mutagenicity Test Data of Existing Chemical Substances
Author:
JETOC
Year:
1996
Bibliographic source:
JETOC

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Principles of method if other than guideline:
The study was performed according to the guidelines of Ministery of Labour, (Japan 1979, 1985 and 1988) and Ames et al. 1975, Maron and Ames (1983) and Matsushima et al. (1980)
- duplicate plates were used instead of triplicate plates but the positive response was confirmed by a repeat experiment.
GLP compliance:
not specified
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
2-chloroethanol
Purity: 99.2 %, Wako Pure Chem. Japan
Lot number: AWH5040

Method

Target gene:
histidine operon
Species / strain
Species / strain / cell type:
other: S. typhimurium TA 100, TA 1535, TA 98, TA 1537 and E.coli. WP2uvrA
Metabolic activation:
with and without
Metabolic activation system:
S9 mix
Test concentrations with justification for top dose:
50, 100, 200, 500, 1000, 2000, 5000 µg/plate
Vehicle / solvent:
Dimethyl sulfoxide
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
Remarks:
dmso
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: see table 1.
Details on test system and experimental conditions:
METHOD OF APPLICATION: preincubation

DURATION
- Preincubation period: 20 minutes
- Exposure duration: 48 hours

selection agent: histidine

NUMBER OF REPLICATIONS: duplicate

NUMBER OF CELLS EVALUATED: all colonies are counted

DETERMINATION OF CYTOTOXICITY
- Method: background lawn
Evaluation criteria:
Chemicals are considered mutagenic when a dose-related increase in revertant colony count is observed and the numer of revertant colonies per plate with the test substance is more than twice that of the negative control (solvent control) and when a reproducibility of the test result is observed.
Statistics:
None

Results and discussion

Test resultsopen allclose all
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:
no cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
Positive controls validity:
valid
Species / strain:
E. coli WP2 uvr A
Metabolic activation:
with
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
Positive controls validity:
valid
Species / strain:
E. coli WP2 uvr A
Metabolic activation:
without
Genotoxicity:
positive
Cytotoxicity / choice of top concentrations:
no cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
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

WP2uvrA positive reponse (average of plates):

µg/plate

- S9 mix

 

Experiment 1

Experiment 2

DMSO

43

50

50

44

-

100

33

-

200

45

-

500

40

45

1000

39

50

2000

65

60

3000

-

90

4000

-

114

5000

186

113

AF2

553

413

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
positive

2-chloroathanl was positive in the Ames test under the conditions of this study. WP2uvrA gave a positive response without metabolic activation. This response was confirmed by an independent repeat. All other strains were negative with and without metabolic activation.
Executive summary:

A study was performed according to JETOC protocols similar to OECD471. The study was performed according to the guidelines of Ministery of Labour, (Japan 1979, 1985 and 1988) and Ames et al. 1975, Maron and Ames (1983) and Matsushima et al. (1980). Deviation from th current OECD guideline is that duplicate plates were used instead of triplicate plates (but the positive response was confirmed by a repeat experiment). 50 -5000 µg/plate 2 -chloroethanol, solvent control and positive controls were applied with and without metabolic activation via the preincubation method to TA 100, TA 1535, TA 98, TA 1537 and WP2uvrA.

WP2uvrA gave a positive response without metabolic activation. This response was confirmed by an independent repeat. All other strains were negative with and without metabolic activation.