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Toxicological information

Genetic toxicity: in vitro

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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:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: GLP - Guideline study with acceptable restrictions. Positive controls were only used in the 20-h treatment.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1995
Report date:
1995

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to guideline
Guideline:
OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)
Deviations:
yes
Remarks:
positive controls were only used in the 20-h treatment
Qualifier:
according to guideline
Guideline:
EU Method B.10 (Mutagenicity - In Vitro Mammalian Chromosome Aberration Test)
Deviations:
yes
Remarks:
positive controls were only used in the 20-h treatment
GLP compliance:
yes
Type of assay:
in vitro mammalian chromosome aberration test

Test material

Constituent 1
Reference substance name:
D-Glucopyranose, oligomeric, C10-16-alkyl glycosides
EC Number:
600-975-8
IUPAC Name:
D-Glucopyranose, oligomeric, C10-16-alkyl glycosides
Details on test material:
- Name of test material (as cited in the study report): trade name given
- Physical state: yellow paste
- Analytical purity: 50% AS in water
- Lot/Batch number: 3BQ12
- Storage conditions: room temperature

Method

Target gene:
Not applicable
Species / strain
Species / strain / cell type:
Chinese hamster lung fibroblasts (V79)
Details on mammalian cell type (if applicable):
- Type and identity of media: Eagle’s Minimal Essential Medium (EMEM) containing 10% (v/v) foetal calf serum, 1% L-glutamine, 1% non-essential amino acids and 2% Penicillin/Streptomycin
- Properly maintained: yes
- Periodically checked for karyotype stability: yes
Metabolic activation:
with and without
Metabolic activation system:
cofactor supplemented post-mitochondrial fraction (S9-mix) (CCR, Rossdorf, Germany), prepared from livers of male Wistar rats induced with Arochlor 1254 (500 mg/kg bw, single i.p. injection)
Test concentrations with justification for top dose:
Preliminary toxicity test: 0.5, 1, 2.5, 5, 10, 25, 50, 100, 250, 500, 1000, 2500 and 5000 µg/mL
7 h and 28 h culture period: 2, 4, 8 and 16 µg/mL (-S9); 20, 40, 80 and 160 µg/mL (+S9)
20 h culture period: 0.5, 1, 2, 4, 8 and 16 µg/mL (-S9); 5, 10, 20, 40, 80 and 160 µg/mL (+S9)

Vehicle / solvent:
- Vehicle(s)/solvent(s) used: medium and DMSO
Controls
Untreated negative controls:
yes
Remarks:
medium
Negative solvent / vehicle controls:
yes
Remarks:
DMSO
True negative controls:
no
Positive controls:
no
Positive control substance:
other: 20 h experiment: ethylmethanesulfonate (EMS), 1.5 mg/mL in nutrient medium, -S9; cyclophosphamide (CP), 1 µg/mL in bidestilled water/nutrient medium, +S9
Details on test system and experimental conditions:
METHOD OF APPLICATION: in medium

DURATION
- Exposure duration: 4 h
- Fixation time (start of exposure up to fixation or harvest of cells): 7, 20, 28 h

SPINDLE INHIBITOR (cytogenetic assays): colcemide 0.4 µg/mL medium (2-2.5 h before harvesting)
STAIN (for cytogenetic assays): Giemsa solution

NUMBER OF REPLICATIONS: duplicate cultures

NUMBER OF CELLS EVALUATED: 100 per culture

DETERMINATION OF CYTOTOXICITY
- Method: relative plating efficiency (preliminary toxicity test); mitotic index of 500 cells (main experiment)

OTHER EXAMINATIONS:
- Determination of polyploidy: yes
Evaluation criteria:
The test substance was classified as mutagenic if a significant, concentration-related increase in the proportion of structural aberrations was induced or a significant positive response for at least one test concentration was found.
The test substance was classified as non-mutagenic in this test system, if neither a significant concentration-related increase in the proportion of structural chromosomal aberrations nor a significant positive response at any of the analysed test substance concentrations was detected.

Results and discussion

Test results
Species / strain:
Chinese hamster lung fibroblasts (V79)
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Remarks:
Preliminary cytotoxicity test: ≥ 5 µg/mL (-S9) and ≥ 100 µg/mL (+S9); main experiment: at 160 µg/mL (+S9, all 3 fixation times)
Vehicle controls validity:
not examined
Untreated negative controls validity:
valid
Positive controls validity:
valid
Additional information on results:
RANGE-FINDING/SCREENING STUDIES:
In the experiment on plating efficiency, strong toxic effects were noticed at ≥ 5 µg/mL without metabolic activation and ≥ 100 µg/mL with S9 mix.

ADDITIONAL INFORMATION ON CYTOTOXICITY:
In the cytogenetic experiment, the test substance was applied up to 16 µg/mL without and 160 µg/mL with metabolic activation. In the experiment without S9 mix, no substantial reduction of the Mitotic Index (MI) was observed at the highest concentration. With metabolic activation, there was no cellular growth to be detected at 160 µg/mL at all three fixation times, and nearly no mitoses to be detected at 80 µg/mL 7 h after treatment. No substantial reduction of the MI was determined at 80 µg/mL after incubation periods of 20 and 28 h. Treatment concentrations for chromosome analysis were selected by evaluating the effect of the test substance on the mitotic index. The highest concentrations chosen for chromosome analysis from the 7, 20 and 28 h harvesting time points were those that resulted in 50-80% reduction of mitotic index or the highest test concentration if no cytotoxicity was observed.
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 without S9 mix

Test item

 

Concentration

Mitotic Index

Aberrant cells in %

in µg/mL

in %

with gaps

without gaps

Exposure period 4 h, fixation time 7 h

Medium

0

100

2.5

1.5

Test substance

16

93

2.5

2

Exposure period 4 h, fixation time 20 h

Medium

0

100

1

0.5

PC (EMS)

1.5

52

28.5

22

Test substance

2

n.d.

2

2

8

80

2.5

2

16

85

5

2

Exposure period 4 h, fixation time 28 h

Medium

0

100

2.5

1

Test substance

16

98

1.5

1.5

PC (positive control): EMS (ethylmethanesulfonate)

Table 2. Test results of experiment with S9 mix

Test item

 

Concentration

Mitotic Index

Aberrant cells in %

in µg/mL

in %

with gaps

without gaps

Exposure period 4 h, fixation time 7 h

Medium

0

100

5

3

Test substance

40

113

3.5

2.5

Exposure period 4 h, fixation time 20 h

Medium

0

100

3.5

2.5

PC (CP)

1

25

34.5

33.5

Test substance

10

n.d.

1.5

0

40

n.d.

3.5

1.5

80

86

5

2

Exposure period 4 h, fixation time 28 h

Medium

0

100

4

2.5

Test substance

80

93

3

3

PC (positive control): CP (cyclophosphamid)

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
negative