Silver docosanoate

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:

experimental study

Adequacy of study:

key study

Study period:

1998

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference 1

Reference Type:

review article or handbook

Title:

SIDS DOCOSANOIC ACID

Author:

METI (former MITI)

Year:

1998

Bibliographic source:

OECD SIDS ; METI (former MITI), Japan (1998)

Reference 2

Reference Type:

study report

Title:

Unnamed

Year:

1998

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)

Deviations:

not applicable

Test guideline 2

Qualifier:

according to guideline

Guideline:

JAPAN: Guidelines for Screening Mutagenicity Testing Of Chemicals

Principles of method if other than guideline:

/

GLP compliance:

yes

Type of assay:

other: not specified

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

Test material form:

other: solid

Details on test material:

- Name of test material (as cited in study report): Docosanoic acid
- Molecular formula (if other than submission substance): C22H44O2
- Molecular weight: 340,58g/mol
- Substance type:Not applicable
- Physical state:solid
- Analytical purity:85.9%
- Impurities (identity and concentrations):c14-C20 fatty acids: ca. 11%; C24 fatty acid: ca. 2%

Method

Target gene:

/

Species / strain

Species / strain / cell type:

Chinese hamster lung (CHL/IU)

Metabolic activation:

with and without

Metabolic activation system:

S9, rat, induced with phenobarbital and 5,6-benzoflavone

Test concentrations with justification for top dose:

350-2800 µg/ml (-S9, 24hr continuous treatment)
288-2300 µg/ml (-S9, 48hr continuous treatment)
875-3500 µg/ml (+/-S9, short term treatment)

Vehicle / solvent:

1 % Carboxymethylcellulose sodium

Controls

Positive controls:

yes

Positive control substance:

cyclophosphamide

mitomycin C

Details on test system and experimental conditions:

For continuous treatment, cells were treated for 24 or 48 hrs without S9. For short-term treatment, cells were treated for 6 hrs with and without S9 and cultivated with fresh media for 18 hrs.

Evaluation criteria:

/

Statistics:

/

Results and discussion

Test results

Species / strain:

Chinese hamster lung (CHL/IU)

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

other: with metabolic activation: no; without metabolic activation: >= 2703 µg/ml (24hr), 2242 g/mL (48hr)

Vehicle controls validity:

not specified

Untreated negative controls validity:

not specified

True negative controls validity:

not specified

Positive controls validity:

valid

Additional information on results:

Fifty percent inhibition of cell proliferation was observed at 2,703 ug/mL for 24hr continuous treatment and at 2,242 ug/mL for 48hr continuous treatment, respectively. Cell proliferation inhibition was not observed in short-term treatment with or without S9 mix.
Structural chromosomal aberrations and polyploidy were not induced up to a maximum concentration of test substance under conditions of continuous treatment, and short-term treatment with and without an exogenous metabolic activa tion system.

Applicant's summary and conclusion

Conclusions:

Chromosomal aberration test in CHL/IU cells was negative with and without metabolic activation.