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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:
migrated information: read-across based on grouping of substances (category approach)
Adequacy of study:
key study
Study period:
October 1978
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: No info on composition. Basic data given, according to guidelines/standards; incomplete reporting

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1978
Report Date:
1978

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
GLP compliance:
no
Remarks:
pre-GLP
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Lot no.: 1814407

Method

Target gene:
Point mutations which involve substitution, addition or deletion of one or a few DNA base pairs
Species / strainopen allclose all
Species / strain / cell type:
S. typhimurium TA 1538
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Additional strain / cell type characteristics:
not applicable
Metabolic activation:
with and without
Metabolic activation system:
no info
Test concentrations with justification for top dose:
0, 0.2, 2, 20, 100 and 500 ug/plate
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: not indicated but should be solubility
Controlsopen allclose all
Untreated negative controls:
no
Negative solvent / vehicle controls:
yes
Remarks:
DMSO
Positive controls:
yes
Positive control substance:
other: 2-acetylaminofluorene (TA98, TA1538), 2-anthramine (TA100, TA1535), 8-aminoquinoline (TA1537)
Remarks:
with metabolic activation
Untreated negative controls:
no
Negative solvent / vehicle controls:
yes
Remarks:
DMSO
Positive controls:
yes
Positive control substance:
other: 2-nitrofluorone (TA98 and TA1538), methylnitrosoguanidine (TA100, TA1535), quinacrine mustard (TA1537)
Remarks:
without metabolic activation
Details on test system and experimental conditions:
METHOD OF APPLICATION: no info

DURATION
- Preincubation period: no info
- Exposure duration: no info (date run was 4 Oct 1978; date read was 6 Oct 1978)

NUMBER OF REPLICATIONS:
3 plates per concentration and strain

DETERMINATION OF CYTOTOXICITY
- Method: observation of the bacterial background lawn for zones of inhibition

Evaluation criteria:
Two times or more the number of spontaneous revertant colonies was considered a positive response.
Statistics:
Not needed.

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:
cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
not examined
Positive controls validity:
valid
Species / strain:
S. typhimurium TA 1538
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
Additional information on results:

ADDITIONAL INFORMATION ON CYTOTOXICITY:
Slight toxicity was seen at 500 and 100 ug dose levels in both activated and non-activated systems and at 20 ug in the non-
activated systen using test strains TA98, TA100, TA1535 and TA1537. No toxicity was seen at all levels using test strain TA1538.

CONTROL COUMPOUNDS:
The responses of teh control compounds were within the limits set for the test, indicating reliability.
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative

The test compound is not genotoxic in vitro in the Salmonella assay using test strains TA98, TA100, TA1535, TA1537, and TA1538. Test strains E. coli WP2 or TA102 were not used.
Executive summary:

Salmonella typhimurium strains TA98, TA100, TA1535, TA1537 and TA1538 were treated with the test compound using the Ames test at 5 dose levels, in triplicate, both with and without metabolic activation. The dose range was determined in a prelimary toxicity assay and was 0.2 to 500 µg/plate. Levels of 20, 100 and 500 µg induced slight toxicity and were also used in the main test. The test was not repeated. The solvent DMSO control plates gave counts of revertant colonies within the normal range. All positive control chemicals produced marked increases in the number of revertant colonies, both with and without metabolic activation. The test compound caused no significant increase in the number of revertant colonies for any of the bacterial strains with or without metabolic activation. The test compound was found to be non-mutagenic under the conditions of this test.