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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro gene mutation study in bacteria
Remarks:
Type of genotoxicity: gene mutation
Type of information:
migrated information: read-across based on grouping of substances (category approach)
Adequacy of study:
key study
Study period:
1996-11-20 to 1997-01-21
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: This study is classified as reliable without restrictions because it is compliant with GLP guidance and internationally accepted study guidelines.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1997
Report Date:
1997

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 471 (Bacterial Reverse Mutation Assay)
Deviations:
no
GLP compliance:
yes
Type of assay:
bacterial reverse mutation assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Silkflo 366 NF polydecene
- Substance type: Poly alpha olefins (1-decene homopolymer hydrogenated)
- Physical state: Colourless liquid
- Analytical purity: Not reported
- Composition of test material, percentage of components: Not reported
- Lot/batch No.: WG080993
- Stability under test conditions: Not reported
- Storage condition of test material: Ambient temperature in the dark
-Other: A homogenous emulsion was produced with surfactants Sorbitan Stearate and Polysornate 60 in order to be suitable for testing.

Method

Target gene:
histidine operon and the trpE locus
Species / strain
Species / strain / cell type:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Additional strain / cell type characteristics:
other: histidine deficient
Metabolic activation:
with and without
Metabolic activation system:
S-9
Test concentrations with justification for top dose:
156.25, 312.5, 625, 1250, 2500, or 5000 µg/plate
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: A homogenous emulsion was produced with surfactants Sorbitan Stearate and Polysornate 60 in order to be suitable for testing.
- Justification for choice of solvent/vehicle: The test compounds oily nature made it impossible to prepare a solution or suspension suitable for testing.
Controls
Untreated negative controls:
yes
Remarks:
untreated
Negative solvent / vehicle controls:
yes
True negative controls:
not specified
Positive controls:
yes
Positive control substance:
other: 2-aminoanthracene; 2-nitrofluorene; methyl methane sulphonate; N-ethyl-N-nitro-N-nitrosoguanidine; 9-aminoacridine
Remarks:
Positive controls were selected based on test strain and presence or absence of S-9
Details on test system and experimental conditions:
METHOD OF APPLICATION: Preincubation


DURATION
- Preincubation period: 20 minutes
- Exposure duration: 2 days


SELECTION AGENT (mutation assays): None


NUMBER OF REPLICATIONS: Two independent studies with three replicates each


DETERMINATION OF CYTOTOXICITY
- Method: Not reported


Evaluation criteria:
A 1.5 to 2-fold increase (depending on the strain) in colony counts with a minimum of 20 colonies necessary, a dose-related response (which may not occur in the high-dose group due to toxicity), and/or reproducible results in the two independent tests.
Statistics:
None reported

Results and discussion

Test results
Species / strain:
S. typhimurium TA 1535, TA 1537, TA 98 and TA 100
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
no cytotoxicity
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid
Additional information on results:
TEST-SPECIFIC CONFOUNDING FACTORS
- Effects of pH: None reported
- Effects of osmolality: None reported
- Evaporation from medium: None reported
- Water solubility: None reported
- Precipitation: Precipitation occurred with the highest concentration (5000 micrograms per plate)


RANGE-FINDING/SCREENING STUDIES: Toxicity tests were performed on TA 100 with doses ranging from 0.1 to 5000 micrograms per plate with no toxicity observed.


C
Remarks on result:
other: all strains/cell types tested
Remarks:
Migrated from field 'Test system'.

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative

Silkflo 366 NF polydecene was not mutagenic.
Executive summary:

In a reverse gene mutation assay in bacteria, strains TA1535, TA1537, TA98, and TA100 of S. typhimurium and Escherichia coli strain WP2uvrA were exposed to a homogeneous emulsion of Silkflo 366 NF polydecene in surfactants, Sorbitan stearate and Polysorbate 60 at concentrations of 156.25, 312.5, 625, 1250, 2500, or 5000 μg/plate in the presence and absence of mammalian metabolic activation using the pre-incubation method.

 

Silkflo 366 NF polydecene was tested up to limit concentrations (5000 μg/plate or 5 mL/plate). The positive controls induced the appropriate responses in the corresponding strains. There was no evidence of induced mutant colonies over background.

 

This study received a Klimisch score of 1 and is classified as reliable without restrictions because it is compliant with GLP guidance and internationally accepted study guidelines.

This study will influence the DNEL.