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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
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment
Justification for type of information:
Data is from publication.

Data source

Reference
Reference Type:
publication
Title:
Methodology for the testing of food dyes for genotoxic activity: experiments with RED 2G (C.I. 18050)
Author:
R.B. Haveland-Smith, R.D. Combes, B.A. Bridges
Year:
1979
Bibliographic source:
Mutation Research, 64 , 241—248

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
other: as mentioned below
Principles of method if other than guideline:
Evaluation of mutagenicity of test chemical in Salmonella typhimurium strain TA1538 in a Fluctuation test.
GLP compliance:
not specified
Type of assay:
bacterial gene mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Test material form:
not specified
Details on test material:
- Name of test material: Red 2G
- Molecular formula: C18H15N3O8S2.2Na
- Molecular weight: 509.426 g/mol
- Substance type: Organic
- Physical state: Aqueous solutions or suspensions
- Purity: 80%
- Impurities (identity and concentrations): As, Pb ,Sb, BaSO4, Cr, Cu, Zn,Free aromatic amines, Synthetic intermediates (excluding free aromatic amines),Subsidiary colours were present.

Method

Target gene:
Histidine
Species / strain
Species / strain:
S. typhimurium TA 1538
Details on mammalian cell lines (if applicable):
Not applicable
Additional strain characteristics:
not specified
Cytokinesis block (if used):
not specified
Metabolic activation:
with and without
Metabolic activation system:
S9 mix consisted of calcium-precipitated microsome from liver of male Sprague-Dawley rats.
Test concentrations with justification for top dose:
Without S9: 10 mg/mlWith S9. 1 or 10 mg/ml
Vehicle:
Deionised water
Controls
Negative controls:
yes
Solvent controls:
yes
True negative controls:
not specified
Positive controls:
yes
Positive control substance:
other: Without S9: Rimmel Mahogany Silk; With S9: 2-acetylaminofluorene
Details on test system and conditions:
METHOD OF APPLICATION: In mediumDURATION- Preincubation period: Overnight (without S9) or overnight (with S9)- Exposure duration: 72 hrs (without S9) or 96 hrs (with S9)- Expression time (cells in growth medium): 72 hrs (without S9) or 96 hrs (with S9)- Selection time (if incubation with a selection agent): No data available- Fixation time (start of exposure up to fixation or harvest of cells): No data availableSELECTION AGENT (mutation assays): No data availableSPINDLE INHIBITOR (cytogenetic assays): No data availableSTAIN (for cytogenetic assays): No data availableNUMBER OF REPLICATIONS: No data availableNUMBER OF CELLS EVALUATED: No data availableDETERMINATION OF CYTOTOXICITY- Method: No data availableOTHER EXAMINATIONS:- Determination of polyploidy: No data available- Determination of endoreplication: No data available- Other: No data availableOTHER: No data available
Rationale for test conditions:
No data available
Evaluation criteria:
The tubes were scored for turbidity. When dyes such as Red 2G was used in this system, it may be impossible to detect the turbidity in the tubes by eye or to use a growth indicator such as bromothymol blue, due to masking by the color. In this case, the presence of viable prototrophic revertants was verified by streaking loopfuls from each tube onto non-supplemented agar.
Statistics:
Yes ,Mean was observed.

Results and discussion

Test results
Species / strain:
S. typhimurium TA 1538
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity:
not specified
Vehicle controls valid:
yes
Negative controls valid:
yes
Positive controls valid:
yes
Remarks on result:
other: No mutagenic effect were observed
Additional information on results:
No data available

Applicant's summary and conclusion

Conclusions:
Test chemical was considered to be negative for mutagenic effects in Salmonella typhimurium strain TA1538 with and without metabolic activation.
Executive summary:

In a Mutagenicity test, the mutagenic effect of test chemical was evaluated in Salmonella typhimurium strain TA1538 utilizing a Fluctuation test. The bacteria were exposed to the test compound at the concentration of 1 or 10 mg /ml in presence or absence of metabolic activation. At the end of the study, the tubes were scored for turbidity. When dyes such as Red 2G was used in this system, it may be impossible to detect the turbidity in the tubes by eye or to use a growth indicator such as bromothymol blue, due to masking by the colour. In this case, the presence of viable prototrophic revertants was verified by streaking loop full from each tube onto non-supplemented agar. As seen by the results, no mutagenic effects of Red 2G were found at 1 or 10 mg/ml in the absence or presence of metabolic activation. Hence, test chemical is considered to be negative for mutagenic effects in Salmonella typhimurium strain TA1538 with and without metabolic activation.