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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:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
1982
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Guideline study without detailed documentation for a read-across substance.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1982
Report Date:
1982

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)
Deviations:
yes
Remarks:
- only 100 metaphase cells were evaluated per dose.
GLP compliance:
no
Type of assay:
in vitro mammalian chromosome aberration test

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Lycasin
- Physical state: Clear liquid
- Lot/batch No.: E664-B
- Storage condition of test material: Tightly capped at room temperature

Method

Species / strain
Species / strain / cell type:
Chinese hamster Ovary (CHO)
Additional strain / cell type characteristics:
not applicable
Metabolic activation:
with and without
Metabolic activation system:
S9 mix (further details not provided)
Test concentrations with justification for top dose:
49, 164, 490, 1640, or 4900 µg/mL (± S9)
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: Distilled, deionized water.
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
Remarks:
- Distilled, deionized water
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: Ethylmethane sulfonate (EMS; - S9) and cyclophosphamide (CP; + S9)
Details on test system and experimental conditions:
METHOD OF APPLICATION: in medium.

DURATION
- Exposure duration: 8 hours (- S9) and 2 hours (+ S9) at 37 ± 0.5 ºC.

SPINDLE INHIBITOR (cytogenetic assays): Colcemid.

NUMBER OF REPLICATIONS: Duplicate flasks used; use of an independent repeat was not reported.

NUMBER OF CELLS EVALUATED: 100 metaphase cells/dose level (50 cells/duplicate flask).
Evaluation criteria:
Chromosomal aberrations were characterized as the following:

- chromatid breaks (including fragments and deletions)
- chromosome breaks (including acentric fragments and minutes)
- chromatid and chromosome gaps
- exchanges (rings, dicentrics, quadriradicals, and triradicals)
- cells with 10 aberrations
- pulverized cells.

Statistics:
Chi-square and one-tailed t-test.

Results and discussion

Test results
Species / strain:
Chinese hamster Ovary (CHO)
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
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 with metabolic activation
negative without metabolic activation