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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro cytogenicity / chromosome aberration study in mammalian cells
Remarks:
Type of genotoxicity: chromosome aberration
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Study conducted according to internationally accepted testing guidelines and performed according to GLP.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1991
Report date:
1991

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)
GLP compliance:
yes
Type of assay:
in vitro mammalian chromosome aberration test

Test material

Constituent 1
Chemical structure
Reference substance name:
Disodium 4,4'-bis[(4-anilino-6-morpholino-1,3,5-triazin-2-yl)amino]stilbene-2,2'-disulphonate
EC Number:
240-245-2
EC Name:
Disodium 4,4'-bis[(4-anilino-6-morpholino-1,3,5-triazin-2-yl)amino]stilbene-2,2'-disulphonate
Cas Number:
16090-02-1
Molecular formula:
C40H38N12Na2O8S2
IUPAC Name:
disodium 5-{[4-(morpholin-4-yl)-6-(phenylamino)-1,3,5-triazin-2-yl]amino}-2-[(E)-2-(4-{[4-(morpholin-4-yl)-6-(phenylamino)-1,3,5-triazin-2-yl]amino}-2-sulfonatophenyl)ethenyl]benzene-1-sulfonate
Test material form:
solid

Method

Species / strain
Species / strain / cell type:
Chinese hamster lung fibroblasts (V79)
Metabolic activation:
with and without
Metabolic activation system:
Aroclor 1254 induced rat liver S9-mix
Test concentrations with justification for top dose:
10 µg/ml (18 hours with and without S-9 mix),
100 µg/ml (18 hours with and without S-9 mix)
150 µg/ml (7, 18 and 28 hours with and without S-9 mix).
Vehicle / solvent:
- Vehicle used: DMSO
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
Remarks:
DMSO
True negative controls:
no
Positive controls:
yes
Positive control substance:
cyclophosphamide
ethylmethanesulphonate
Remarks:
-S9-mix: ethylmethanesulphonate; +S9-mix: cyclophosphamide
Details on test system and experimental conditions:
PREPARATION
Preparation of chromosomes was done 7 hours (high dose), 18 hours (low, medium and high dose) and 28 hours (high dose) after start of incubation with the test item. The incubation interval was 4 hours.

TEST SYSTEM
- Replicates: in each experimental group two parallel cultures were used.
- Culture: per culture 100 metaphases were scored for structural chromosome aberrations.
- Dose levels: 10 µg/ml (18 hours with and without S-9 mix), 100 µg/ml (18 hours with and without S-9 mix) and 150 µg/ml (7, 18 and 28 hours with and without S-9 mix).
- Dose selection rationale: the concentration range of the test item applied was determined in a pre-experiment using the plating efficiency assay as indicator for toxicity response.
Evaluation criteria:
A test article is classified as mutagenic if it induces either a significant dose-related increase in the number of structural chromosomal aberrations or a significant positive response for at least one of the test points. A test article producing neither a significant dose-related increase in the number of structural chromosomal aberrations nor a significant positive response at any one of the test points is considered non-mutagenic in this system.
This can be confirmed by means of the chi-square test. However, both biological and statistical significance should be considered together.
Statistics:
Statistical significance at the five per cent level (p < 0.05) was evaluated by means of the chi-square test. Evaluation was performed only for cells carrying aberrations exclusive gaps.

Results and discussion

Test results
Species / strain:
Chinese hamster lung fibroblasts (V79)
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Remarks:
The mitotic index was at least slightly reduced after treatment with the highest scorable concentration in the absence (7 h and 28 h) and presence (7 h and 18 h) of S9 mix.
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Additional information on results:
RANGE-FINDING/SCREENING STUDIES:
In the pre-test, treatment with the highest concentration of 150 µg/ml did not reduce the plating efficiency of the cells. However, in the cytogenetic experiment the mitotic index was reduced after treatment with the highest concentration at fixation intervals of 7 and 18 hours in the presence of S9 mix and after 7 and 28 hours in the absence of S9 mix, indicating that FWA-1 had cytotoxic properties under these conditions.
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.

Any other information on results incl. tables

Both, in the absence and presence of S9 mix the test article did not increase the frequency of cells with aberrations at any fixation interval. The aberration rates of the cells after treatment with the test article (0.0 % - 2.0 %) were in or near to the range of the control values; 0.0 % - 1.0 %. At fixation interval 28 h in the presence of S9 mix, the statistical evaluation of the data revealed a significant deviation of the aberration rate in the culture treated with the test article (2.00 %) as compared to the corresponding control culture. However, this results was due to the extremely low aberration rate (0.00 %) in the control culture. As the aberration rate of the treatment group is within the range of our histrorical data (0.00 % - 4.00 %) this result is not regarded as biologically relevant.

 

No relevant deviation from the control data was found in the groups treated with the test article.

EMS (0.72 mg/ml) and CPA (1.40 µg/ml) were used as positive controls and showed distinct increases in cells with structural chromosome aberrations.

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative

The test substance did not induce structural chromosome aberrations in the V79 Chinese hamster cells.
Executive summary:

Method

The genetic toxicity potential of the test item was assessed testing the substance in the Chinese hamster lung fibroblasts (V79), in absence and the presence of metabolic activation by rat liver S-9 mix., according to the procedures outlined into the OECD guideline 473.

Results

Both, in the absence and presence of S9 mix the test article did not increase the frequency of cells with aberrations at any fixation interval. The aberration rates of the cells after treatment with the test article (0.0% - 2.0%) were in or near to the range of the control values.

In conclusion, it can be stated that in the described study and under the experimental conditions reported, the test article did not induce structural chromosome aberrations in the V79 Chinese hamster cell line.