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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 based on grouping of substances (category approach)
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
GLP - Guideline study, tested with the source substance CAS 112-85-6. In accordance to the ECHA guidance document "Practical guide 6: How to report read-across and categories (March 2010)", the reliability was changed from RL1 to RL2 to reflect the fact that this study was conducted on a read-across substance.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2002

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)
Deviations:
no
Qualifier:
according to
Guideline:
JAPAN: Guidelines for Screening Mutagenicity Testing Of Chemicals
Deviations:
no
GLP compliance:
yes
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): Docosanoic acid
- Physical state: white solid
- Analytical purity: 85.9 %
- Lot/batch No.: 60805X
- Storage condition of test material: The test substance was kept under room temperature before use.

Method

Target gene:
not applicable
Species / strain
Species / strain:
other: Chinese hamster lung (CHL) cells
Details on mammalian cell lines (if applicable):
- Type and identity of media: Eagle-MEM liquid medium
- Properly maintained: yes
Additional strain characteristics:
not specified
Metabolic activation:
with and without
Metabolic activation system:
S9 from rat liver, induced with phenobarbital and 5,6-benzoflavone
Test concentrations with justification for top dose:
-S9 mix (short-term exposure): 0, 875, 1750, 3500 µg/mL
+S9 mix (short-term exposure): 0, 875, 1750, 3500 µg/mL
-S9 mix (24-hour continuous exposure): 0, 350, 700, 1400, 2800 µg/mL
-S9 mix (48-hour continuous exposure): 0, 288, 575, 1150, 2300 µg/mL
Vehicle:
1.0 % Carboxymethylcellulose sodium
Controls
Negative controls:
not specified
Solvent controls:
yes
True negative controls:
not specified
Positive controls:
yes
Positive control substance:
other: continuous exposure: Mitomycin C (0.05 µg/mL for 24 hours and 0.025 µg/mL for 48 hours); short-term exposure, Cyclophosphamide (12.5 µg/mL)
Details on test system and conditions:
METHOD OF APPLICATION: in medium

DURATION
- Preincubation period: 3 days
- Exposure duration: 6 (short-term exposure), 24, 48 hours

STAIN (for cytogenetic assays): Giemsa

NUMBER OF CELLS EVALUATED: 200

DETERMINATION OF CYTOTOXICITY
- Method: relative total growth

Evaluation criteria:
The frequency of polyploid cells or cells with abnormal structure of each test group were determined according to the criteria of Ishidate.

Results and discussion

Test results
Species / strain:
other: Chinese hamster lung (CHL) cells
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity:
no
Vehicle controls valid:
yes
Negative controls valid:
not specified
Positive controls valid:
yes
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.
Additional information on results:
TEST-SPECIFIC CONFOUNDING FACTORS
- Water solubility: insoluble in water, soluble in alcohol, ether, chloroform and acetone
- Precipitation: observed on the slide of continuous exposure high dose group

RANGE-FINDING/SCREENING STUDIES: see 'Any other information on material and method incl. tables'

COMPARISON WITH HISTORICAL CONTROL DATA: this test was valid, since the frequency of chromosomal aberration in positive control was within background data.

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative

The test substance did not induce structural chromosomal aberrations in the absence or presence of an exogenous metabolic activation system.