2,2-dimethyl-1,3-propanediyl didecanoate

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Type of information:

experimental study

Adequacy of study:

key study

Study period:

16 Aug 2012- 24 Jan 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)

Version / remarks:

adopted in 1997

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.10 (Mutagenicity - In Vitro Mammalian Chromosome Aberration Test)

Version / remarks:

adopted in 2008

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.5375 - In vitro Mammalian Chromosome Aberration Test

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

The department of health of the government of the United Kingdom

Type of assay:

other: in vitro mammalian chromosome aberration test

Test material

Test material information

Constituent 1

Reference substance name:

Heptanoic acid, ester with 2,2-dimethyl-1,3-propanediol

EC Number:

272-469-1

EC Name:

Heptanoic acid, ester with 2,2-dimethyl-1,3-propanediol

Cas Number:

68855-18-5

IUPAC Name:

68855-18-5

Method

Target gene:

not applicable

Species / strain

Species / strain / cell type:

lymphocytes:

Details on mammalian cell type (if applicable):

- Type and identity of media: Eagle´s minimal essential medium with HEPES buffer (MEM) supplemented with L-glutamine, penicillin/streptomycin, amphotericin B and 10% foetal bovine serum (FBS).
- Properly maintained: yes
- Periodically checked for Mycoplasma contamination: no data
- Periodically checked for karyotype stability: no data
- Periodically "cleansed" against high spontaneous background: no data

Metabolic activation:

with and without

Metabolic activation system:

cofactor supplemented post-mitochondrial fraction (S9 mix), prepared from the livers of rats treated with phenobarbonel/beta-naphthoflavone

Test concentrations with justification for top dose:

12.5, 25, 50, 100, 200 and 400 µg/mL

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: acetone (test substance), dimethyl sulphoxide (cyclophosphamide), and Minimal Essential Medium (mytomicin C)

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

Acetone

True negative controls:

no

Positive controls:

yes

Positive control substance:

cyclophosphamide

mitomycin C

Remarks:

+S9, cyclophosphamide, 5 µg/mL in dimethyl sulphoxide; -S9; mitomycin C, 0.4 µg/mL in Exp1, and 0.2 µg/mL in Exp 2, –S9 in Minimal Essential Medium.

Details on test system and experimental conditions:

METHOD OF APPLICATION: in medium
DURATION
- Exposure duration: 4 and 24 h
- Fixation time (start of exposure up to fixation or harvest of cells): 4h treatment: 24 h; 24 h treatment: 24 h

SPINDLE INHIBITOR (cytogenetic assays): democolcine (Colcemid 0.1 µg/mL)
STAIN (for cytogenetic assays): Giemsa 5%

NUMBER OF REPLICATIONS: duplicate in two independent experiments

NUMBER OF CELLS EVALUATED: 100 well-spread metaphases per culture

DETERMINATION OF CYTOTOXICITY
- Method: mitotic index of 2000 lymphocyte cell nuclei
OTHER EXAMINATIONS:
- Determination of polyploidy: yes

Evaluation criteria:

A positive response was recorded for a particular treatment if the % cells with aberrations, excluding gaps, markedly exceeded that seen in the concurrent control, either with or without a clear dose-relationship. For modest increased in aberration frequency a dose response relationship is generally required and appropriate statistical tests may be applied in order to record a positive response.

Statistics:

The frequency of cells with aberrations excluding gaps and the frequency of polyploid cells was compared, when necessary, with the concurrent vehicle control value using the Fisher´s Exact test.

Results and discussion

Test results

Key result

Species / strain:

lymphocytes: human lymphocytes

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

In Exp 1, -S9, there was a plateau in toxicity between 50 and 400 µg/mL. In Exp 2 at 400 µg/mL (inhibition 45% of mitotic index).

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Effects of pH: there was no significant change in pH when the test item was dosed into media
- Effects of osmolality: the osmolality did not increase by more than 50 mOsm

RANGE-FINDING/SCREENING STUDIES: Mitotic index data was used to estimate test item toxicity and for selection of the dose levels for the main test.

Applicant's summary and conclusion

Conclusions:

Based on the results of the conducted study, the test substance did not exhibit clastogenic properties.