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Toxicological information

Genetic toxicity: in vitro

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Administrative data

Endpoint:
in vitro DNA damage and/or repair study
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference
Reference Type:
publication
Title:
Chromosome aberration and sister chromatid exchange tests in Chinese hamster ovary cells in vitro. II. Results with 20 chemicals
Author:
Loveday KS, et al.
Year:
1989
Bibliographic source:
Environ. Mol. Mutagen., 13, 60-94

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 479 (Genetic Toxicology: In Vitro Sister Chromatid Exchange Assay in Mammalian Cells)
GLP compliance:
not specified
Type of assay:
sister chromatid exchange assay in mammalian cells

Test material

Reference
Name:
Unnamed
Type:
Constituent

Method

Species / strain
Species / strain / cell type:
Chinese hamster Ovary (CHO)
Metabolic activation:
with and without
Metabolic activation system:
rat liver S9 (Aroclor 1254-induced)
Test concentrations with justification for top dose:
150, 500, 1500 µg/mL
Vehicle / solvent:
- Vehicle(s)/solvent(s) used: water
Controls
Untreated negative controls:
yes
Negative solvent / vehicle controls:
yes
True negative controls:
no
Positive controls:
yes
Positive control substance:
other: cyclophosphamide (with S9); mitomycin C (without S9)
Statistics:
Statistical analyses were conducted on the slopes of the dose-response curves and the individual dose points.

Results and discussion

Test results
Key result
Species / strain:
Chinese hamster Ovary (CHO)
Metabolic activation:
with and without
Genotoxicity:
negative
Cytotoxicity / choice of top concentrations:
cytotoxicity
Remarks:
1500 µg/ml
Vehicle controls validity:
valid
Untreated negative controls validity:
valid
Positive controls validity:
valid

Any other information on results incl. tables

Results summary:

The test substance did not induce sister chromatid exchanges in CHO cell and thus, showed no mutagenic potential under the chosen test condition.

The sensitivity of the test system was verified since the positive control substances showed the expected positive reactions

Detailed results:

Induction of sister chromatid exchanges in Chinese hamster ovary cells
without metabolic activation:
       

Treatment (µg/mL)

Cells

No. SCE        

SCE/chromosome        

SCE/cells

Medium

50

465

0.44                

9.3

Mitomycin C (0.002)        

50

727

0.69                

14.5

Mitomycin C (0.010)        

10

319

1.54                

31.9

DEA (150)

50

459 

0.43                

9.2

DEA (500)

50

487

0.46                

9.7

DEA (1500)

50

469

0.45                

9.4

                                         
with metabolic activation:
                                                        

Treatment (µg/mL)

Cells

No. SCE        

SCE/chromosome        

SCE/cells

Medium

50

518

0.51                

10.4

Cyclophosphamide (0.5)        

50

1053

1.03                

21.1

Cyclophosphamide (2.5)        

10

592        

2.94                

59.2

DEA (150)

50

505 

0.49

10.1

DEA (500)

50

539

0.53                

10.8

DEA (1500)

50

565

0.56                

11.3

                                                                        

Applicant's summary and conclusion