Fatty acids, C8-10 and C18-unsatd., diesters with neopentyl glycol

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:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP-Guideline study. According 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:

2012

Report date:

2012

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

GLP compliance:

yes (incl. QA statement)

Remarks:

Department of Health of the Government of the United Kingdom, UK

Type of assay:

in vitro mammalian chromosome aberration test

Test material

Test material information

Constituent 1

Reference substance name:

Fatty acids, C8-18 and C18-unsatd., esters with neopentyl glycol

EC Number:

286-072-6

EC Name:

Fatty acids, C8-18 and C18-unsatd., esters with neopentyl glycol

Cas Number:

85186-86-3

IUPAC Name:

85186-86-3

Details on test material:

- Name of test material (as cited in study report): only trade name given
- Physical state: yellow liquid
- Analytical purity: 100%
- Lot/batch No.: OE10817
- Storage condition of test material: room temperature in the dark

Method

Target gene:

Not applicable

Species / strain

Species / strain / cell type:

lymphocytes: cultured peripheral human lymphocytes

Details on mammalian cell type (if applicable):

- Type and identity of media:
Eagle’s minimal essential medium with HEPES buffer (MEM) supplemented “in-house” with L-glutamine, supplemented with
- penicillin/streptomycin
- amphotericin B
- 10% foetal bovine serum (FBS)

Metabolic activation:

with and without

Metabolic activation system:

cofactor supplemented post-mitochondrial fraction (S9 mix), prepared from the livers of rats with a mixture of phenobarbitone and beta-naphthoflavone

Test concentrations with justification for top dose:

4 (20)-hour without S9: 40, 80, 160, 320, 480, 640, 960, 1280 µg/mL
4 (20)-hour withS9 (2%): 40, 80, 160, 320, 480, 640, 960, 1280 µg/mL

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: acetone

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

acetone

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: mitomycin C, 0.4 and 0.2 µg/mL (exp 1 and exp 2, respectively); cyclophosphamide, 5 µg/mL in both experiments

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): 24 h

SPINDLE INHIBITOR (cytogenetic assays): colchicine 0.1 µg/mL
STAIN (for cytogenetic assays):

NUMBER OF REPLICATIONS: 2

NUMBER OF CELLS EVALUATED: 100

DETERMINATION OF CYTOTOXICITY
- Method: mitotic index

OTHER EXAMINATIONS:
- Determination of polyploidy: yes

Evaluation criteria:

A test substance was considered positive in the chromosome aberration test if: a) It induced a dose-related marked increase in the % of cells with chromosome aberrations b) It induced a marked increase in the % of cells with chromosome aberrations in absence of a clear-dose response relationship. For the modest increases in aberration frequency a dose response relationship was generally required together with appropriate statistical tests.

Statistics:

Fisher´s Exact test

Results and discussion

Test results

Species / strain:

lymphocytes: cultured peripheral human lymphocytes

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

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.
Precipitation: Experiment 1: A greasy/oily precipitate of the test item was observed at the end of exposure, at and above 160 µg/mL, in the 4(20)-hour exposure group in the absence of S9, and at and above 80 µg/mL, in the 4(20)-hour exposure group in the presence of S9.

Experiment 2: A greasy/oily precipitate of the test item was observed at the end of exposure, at and above 80 µg/mL, in the 4(20)-hour exposure group in the presence of S9. In the 24 hour exposure group in the absence of S9 a cloudy precipitate was observed at the end of exposure at and above 80 µg/mL oily precipitate was not noted at and above 160 µg/mL.

RANGE-FINDING/SCREENING STUDIES:
The selection of the maximum dose level for Experiment 1 and Experiment 2 was based on the toxicity seen around the onset of precipitating dose levels and was 1280 µg/mL for the 4(20)-hour exposure groups and for the continuous exposure group. It was considered that above this dose level the exposure of the cells to the test item was reduced due to the item forming a greasy/oily precipitate and this was indicated by absence of S9 and continuous exposure group.

COMPARISON WITH HISTORICAL CONTROL DATA:
Many experiments with human lymphocytes have established a range if aberration frequencies acceptable for control cultures.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Table 1. Test results of experiment I.

 

Test item	Concentration	Mitotic Index	Aberrant cells in %
	in µg/mL	in %	with gaps	without gaps
Treatment period 4 h, without S9 mix
Acetone	0	100	0.0	0.0
MMC	0.4	39	5.0	51.0
Test substance	80	106	0.0	0.5
	320	91	0.0	0.5
	640	122	0.0	0.5
	1280	123	0.0	0.0
Treatment period 4 h, with S9 mix
Acetone	0	100	0.5	1.0
CP	5	32	12.7	20.7
Test substance	40	102	2.0	1.0
	320	83	0.0	0.5
	640	66	0.0	0.5
	1280	98	0.5	0.0

MMC: Mitomycin C; CP: Cyclophosphamide (positive controls)

Table 2. Test results of experiment II.

Test item	Concentration	Mitotic Index	Aberrant cells in %
	in µg/mL	in %	with gaps	without gaps
Treatment period 24 h, without S9 mix
Acetone	0	100	0	0.5
MMC	0.2	24	7.0	31.0
Test substance	40	106	1.0	0.0
	160	83	1.5	0.0
	640	76	0.5	0.0
	1280	78	1.0	0.0
Treatment period 4 h, with S9 mix
Acetone	0	100	0.0	1.0
CP	5	24	2.7	20.7
Test substance	40	110	0.5	1.0
	320	64	0.0	0.5
	640	62	0.0	0.5
	1280	67	0.0	0.0

MMC: Mitomycin C; CP: Cyclophosphamide (positive controls)

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative