Sorbitan tristearate

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:

26 Mar to 09 May 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

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:

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

Deviations:

no

GLP compliance:

yes

Type of assay:

in vitro mammalian chromosome aberration test

Test material

Test material information

Constituent 1

Reference substance name:

Sorbitan laurate

EC Number:

215-663-3

EC Name:

Sorbitan laurate

Cas Number:

1338-39-2

IUPAC Name:

1,4-anhydro-6-O-dodecanoyl-D-glucitol

Details on test material:

- Name of test material (as cited in study report): sorbitan laurate
- Physical state: yellow turbid viscous liquid
- Analytical purity: >80%
- Lot/batch No.: 0000357933
- Expiration date of the lot/batch: 27 October 2011
- Storage condition of test material: stable at 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: RPMI 1640 medium supplemented with 20% (v/v) FCS, 2 mM L-glutamine, penicillin/streptomycin (50 U/mL and 50 mG/mL respectively) and 30 U/mL heparin
- Properly maintained: yes

Metabolic activation:

with and without

Metabolic activation system:

cofactor supplemented post-mitochondrial fraction (S9 mix), prepared from the livers of rats treated with a combination of phenobarbital and beta-naphtoflavone

Test concentrations with justification for top dose:

3 h exposure time: 33, 100 and 333 µg/mL
24 h exposure time: 50, 100 and 600 µg/mL
48 h exposure time: 100, 450 and 500 µg/mL

Vehicle / solvent:

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

Controls

Controls 1

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

cyclophosphamide

Remarks:

with rat liver S9-mix

Migrated to IUCLID6: 10 µg/mL for a 3 h exposure period (24 h fixation time)

Controls 2

Untreated negative controls:

yes

Negative solvent / vehicle controls:

yes

Remarks:

DMSO

True negative controls:

no

Positive controls:

yes

Positive control substance:

mitomycin C

Remarks:

without rat liver S9-mix

Migrated to IUCLID6: 0.5 µg/mL for a 3 h exposure period, 0.2 µg/mL for a 24 h exposure period and 0.1 µg/mL for a 48 h exposure period

Details on test system and experimental conditions:

METHOD OF APPLICATION: in medium

DURATION
- Exposure duration: 3, 24 and 48 h
- Fixation time (start of exposure up to fixation or harvest of cells): 3 h treatment: 24 and 48 h; 24 h treatment: 24 h; 48 h treatment: 48 h

SPINDLE INHIBITOR (cytogenetic assays): colchicine 0.5 µL/mL medium
STAIN (for cytogenetic assays): Giemsa 5% (v/v) in tap water

NUMBER OF REPLICATIONS: 2

NUMBER OF CELLS EVALUATED: 100 per culture

DETERMINATION OF CYTOTOXICITY
- Method: mitotic index of 1000 cells

OTHER EXAMINATIONS:
- Determination of polyploidy: yes

Evaluation criteria:

A test substance was considered positive (clastogenic) in the chromosome aberration test if: a) It induced a dose-related statistically significant (Chi-square test, one-sided, p < 0.05) increase in the number of cells with chromosome aberrations. b) A statistically significant and biologically relevant increase in the frequencies of the number of cells with chromosome aberrations was observed in the absence of a clear dose-response relationship.
A test substance was considered negative (not clastogenic) in the chromosome aberration test if none of the tested concentrations induced a statistically significant (Chi-square test, one-sided, p < 0.05) increase in the number of cells with chromosome aberrations. The preceding criteria are not absolute and other modifying factors might enter into the final evaluation decision.

Statistics:

Chi-square test, one-sided, p < 0.05

Results and discussion

Test results

Species / strain:

lymphocytes: cultured human peripheral lymphocytes

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

no cytotoxicity, but tested up to precipitating concentrations

Vehicle controls validity:

valid

Untreated negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

TEST-SPECIFIC CONFOUNDING FACTORS
- Precipitation: At a concentration of 333 µg/mL and higher sorbitan laurate precipitated in the culture medium

RANGE-FINDING/SCREENING STUDIES: The highest concentration analysed was selected based on the solubility of the test substance in the culture medium (3 h and 24 h continuous exposure) or on toxicity inhibition of the mitotic index of about 50% or greater (48 h continuous exposure).

Any other information on results incl. tables

  Table 1: Maximum number of cells with aberrations (with gaps)

	Maximum number of cells with aberrations [%](with gaps)
	solvent control		positive control		treatment (conc. µg/mL)
treatment [exposure time/fixation time]	with S9-mix	without S9-mix	with S9-mix	without S9-mix	with S9-mix	without S9-mix
3h/24h	2	7	31	24	3 (100)	5 (100)
3h/48h	3	-	29	-	2 (33)	-
24h/24h	-	1	-	32	-	3 (600)
48h/48h	-	1	-	26	-	4 (450)

Table 2: Maximum number of cells with aberrations without gaps

	Maximum number of cells with aberrations [%](without gaps)
	solvent control		positive control		treatment (conc. µg/mL)
treatment [exposure time/fixation time]	with S9-mix	without S9-mix	with S9-mix	without S9-mix	with S9-mix	without S9-mix
3h/24h	1	5	30	24	2 (333)	4 (333)
3h/48h	3	-	28	-	1 (33)	-
24h/24h	-	1	-	32	-	2 (100)
48h/48h	-	1	-	26	-	4 (450)

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information):
negative