Glycerides, C18-36

Genetic toxicity: in vitro

Some information in this page has been claimed confidential.

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:

weight of evidence

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

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

Method

Target gene:

Not applicable

Species / strain

Species / strain / cell type:

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

Details on mammalian cell type (if applicable):

- Type and identity of media: MEM medium supplemented with 10% calf serum

Additional strain / cell type characteristics:

not specified

Metabolic activation:

with and without

Metabolic activation system:

cofactor supplemented post-mitochondrial fraction (S9 mix), prepared from the livers of rats treated with phenobarbital and 5,6-benzoflavone

Test concentrations with justification for top dose:

6h treatment with and without S9 mix: 891, 1783, 3565 µg/mL
24h treatment without S9 mix: 55.7, 111, 223, 446 µg/mL

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of vehicle: due to limited solubility of the test substance in water, DMSO was selected as vehicle.

Controls

Untreated negative controls:

no

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

other: -S9: mitomycin C (MMC), 0.1 µg/mL (6h exposure), 0.05 µg/mL (24h exposure); +S9: cyclophosphamide (CM), 10 µg/mL

Details on test system and experimental conditions:

METHOD OF APPLICATION: in medium

DURATION
- Exposure duration: 6 h (short treatment) and 24 h (continuous treatment)
- Expression time (cells in growth medium): 18 h (after 6 h treatment)
- Fixation time (start of exposure up to fixation or harvest of cells): 24 h

SPINDLE INHIBITOR: 0.2 μg/mL of colcemid (added 2 h prior to harvest)
STAIN: 1.2% Giemsa stain (in sodium phosphoric acid buffer 1/100 mol/L pH 6.8) for 12 min

NUMBER OF REPLICATIONS: 2 replications in one experiment

NUMBER OF CELLS EVALUATED: 100 per culture

DETERMINATION OF CYTOTOXICITY
- Method: relative cell growth

OTHER EXAMINATIONS:
- Determination of polyploidy: Yes

Evaluation criteria:

100 cells/plate were observed and classified into gap, ctd (chromatid break), cte (chromatid exchange), csb (chromosome break), cse (chromosome exchange) and oth (others). The total number of cells with aberrations excluding gaps was calculated. The number of polyploid cells was also counted.
The test results were considered positive, if a statistically significant increase in the frequency of chromosome aberrations was observed, the increase showed dose-dependency and it was reproducible.

Statistics:

Differences in chromosome aberration frequencies between treated and control cells were analysed with the Fisher's exact test (p < 0.025). Dose-dependency was assessed using the Cochran Armitage trend test.

Results and discussion

Test results

Key result

Species / strain:

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

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

cytotoxicity

Remarks:

at 446 µg/mL (24 h treatment, without metabolic activation)

Vehicle controls validity:

valid

Untreated negative controls validity:

not examined

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Water solubility: the test substance was not soluble in water.
- Precipitation: visible precipitation was noted at 223 µg/mL and above.

RANGE-FINDING/SCREENING STUDIES:
To find the appropriate concentration range, a cytotoxicity test was performed at test concentrations of 3565, 1783, 891, 446, 223, 111, 55.7, 27.9, 13.9, 6.96 µg/mL. Cytotoxicity was evaluated both after a continuous 24 h exposure (-S9 mix) and a short-term 6 h exposure (± S9 mix) followed by an 18 h recovery period prior to harvest.
The test substance was not cytotoxic after short-term exposure at any concentration in the presence of S9 mix. Without metabolic activation, relative growth was reduced to about 71% of the control value.
After 24 h continuous treatment without S9 mix, the test substance was not cytotoxic up to 1783 µg/mL. At 3565 µg/mL, relative growth was decreased to ca. 13 % of the control value. The concentration leading to 50% cytotoxicity was calculated to be 2738 µg/mL.
Based on these results, the main test was conducted using the following test substance concentrations:
6 h treatment (± S9 mix): 891, 1783 and 3565 µg/mL
24 h treatment (-S9 mix): 55.7, 111, 223 and 446 µg/mL

ADDITIONAL INFORMATION ON CYTOTOXICITY:
In the main test, no cytotoxic effects were observed after short-term exposure. The test substance was cytotoxic at 446 µg/mL after the 24 h treatment.

Remarks on result:

other: all strains/cell types tested

Remarks:

Migrated from field 'Test system'.

Any other information on results incl. tables

Table 1. Results of main study (short-term treatment) and additional study (continuous treatment)

Test item	Concentration	Relative cell growth	Aberrant cells in %
	in μg/mL	in %	with gaps	without gaps
Exposure period 6h, fixation time 18h, without S9 mix
DMSO		100	1	1
Glycerol monooleate	891 a)	121.8	0	1
	1783 a)	114.8	1	0
	3565 a)	101.1	1.5	0.5
MMC	0.1	77.5	4.5	36*
Exposure period 6h, fixation time 18h, with S9 mix
DMSO		100	0.5	0
Glycerol monooleate	891 a)	135.9	2	2
	1783 a)	123.9	1	0.5
	3565 a)	111.4	1	0.5
CP	12.5	83.4	3.5	19.5*
Exposure period 24h, without S9 mix
DMSO		100	1	1
Glycerol monooleate	55.7	99	0.5	0
	111	105.9	1	1
	223 a)	87.0	0.5	0
	446 a)	91.6	Toxic
MMC	0.05	104.4	6.5	25*

*: Significant difference from control (Fisher's exact test, p < 0.025)

a): Visible precipitation was observed at the end of exposure period.