Fatty acids, C18-unsatd.

Genetic toxicity: in vitro

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 guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

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

Test material information

Constituent 1

Reference substance name:

Docosanoic acid

EC Number:

204-010-8

EC Name:

Docosanoic acid

Cas Number:

112-85-6

Molecular formula:

C22H44O2

IUPAC Name:

docosanoic acid

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 / cell type:

mammalian cell line, other: Chinese hamster lung (CHL) cells

Details on mammalian cell type (if applicable):

- Type and identity of media: Eagle-MEM liquid medium
- Properly maintained: yes

Additional strain / cell type 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 / solvent:

1.0 % Carboxymethylcellulose sodium

Controls

Untreated negative controls:

not specified

Negative solvent / vehicle 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 experimental 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:

mammalian cell line, other: Chinese hamster lung (CHL) cells

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity

Vehicle controls validity:

valid

Untreated negative controls validity:

not specified

Positive controls validity:

valid

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.

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