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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:
experimental study
Adequacy of study:
key study
Study period:
2001
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: The study was performed in accordance with the OECD guideline 473, and in compliance with GLP standard.
Cross-reference
Reason / purpose:
reference to same study

Data source

Reference
Reference Type:
publication
Title:
Unnamed
Year:
2006

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 473 (In Vitro Mammalian Chromosome Aberration Test)
Deviations:
not specified
Qualifier:
according to
Guideline:
JAPAN: Guidelines for Screening Mutagenicity Testing Of Chemicals
Deviations:
not specified
GLP compliance:
yes
Type of assay:
in vitro mammalian chromosome aberration test

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Test material form:
solid: particulate/powder
Remarks:
migrated information: powder
Details on test material:
- Name of test material (as cited in study report): 4,4'-Oxybis(benzenesulfonyl hydrazide)
- Analytical purity: no data
- Purity test date: 99.3 wt%
- Lot/batch No.: 403650

Method

Target gene:
NA
Species / strain
Species / strain:
other: Chinese Hamster Lung (CHL/IU) Cells
Details on mammalian cell lines (if applicable):
NA
Additional strain characteristics:
not specified
Metabolic activation:
with and without
Metabolic activation system:
rat, malem, liver, 30% S9 mix induced with phenobarbital and 5,6-benzoflavone
Test concentrations with justification for top dose:
Absence metabolic system; 0, 557, 696, 870, 1,088, 1,360, and 1,700 µg/mL
Presence metabolic system; 0, 357, 446, 557, 696, 870, and 1,088 µg/mL
Vehicle:
- Vehicle(s)/solvent(s) used: DMSO
- Justification for choice of solvent/vehicle: no data
Controls
Negative controls:
yes
Remarks:
solvent
Solvent controls:
yes
Remarks:
DMSO
True negative controls:
no
Positive controls:
yes
Positive control substance:
cyclophosphamide
mitomycin C
Details on test system and conditions:
Culture establishment: CHL cells in logarithmic were to maintain low aberration frequencies. Subcultured at low density, before over growth occurs. The cells were incubated at 37 C in atmosphere of 5 % (v/v) CO2 and 100 % humidity.

Description of follow up repeat study: Series of seven and ten concentration levels with 1.25-fold intervals were tested in the absence and the presence of metabolic activation system.
Evaluation criteria:
The test was considered as positive in this assay if; 1) Statistically significant increase in the proportion of cells with structural aberrations (excluding gaps) occurs at one or more concentration levels 2) 1) exceed the normal range, 3) If the result of 1) is reproducible.
Statistics:
Fisher’s exact test and Chochran Armitage’s trend test (p-value: 0.05)

Results and discussion

Test results
Species / strain:
other: Chinese Hamster Lung (CHL/IU) Cells
Metabolic activation:
with and without
Genotoxicity:
positive
Cytotoxicity:
yes
Remarks:
-S9: at 1360 µg/mL and above. +S9: at 696µg/mL and above
Vehicle controls valid:
yes
Negative controls valid:
yes
Positive controls valid:
yes
Additional information on results:
None

Any other information on results incl. tables

Table 1. Chromosome aberration test on CHL cells treated with 4,4’-oxybis(benzenesulfonylhydrazide) [short-term treatment: -S9 mix]

Compound

Concentration (mg/mL)

Time of exposure (hr)

Relative cell growth (%)

No. of cells analyzed

No. of cells with aberrations –gap (%)

No. of cells analyzed for polyploid

No. of polyploid cells (%)

Final Judgment

DMSOa)

0

6

100.0

200

0 (0.0)#

200

1 (0.5)

 

Test substance

557

6

47.7

200

8 (4.0)*

200

1 (0.5)

 

696

6

37.7

200

21 (10.5)*

200

4 (2.0)

 

870

6

33.1

200

27 (13.5)*

200

0 (0.0)

Positive

1088

6

18.0

200

6 (3.0)*

200

2 (1.0)

 

1360c)

6

9.1

Toxic

 

 

 

 

1700c)

6

3.0

Toxic

 

 

 

 

MMCb)

0.1

6

57.2

200

88 (44.0)*

200

0 (0.0)

Positive

-gap: total number of cells with aberrations except gap

# p≤0.05: Significant difference by trend test (Cochran-Armitage trend test)

* p≤0.05: Significant difference from the negative control group (Fisher’s exact test)

a) Negative control (Dimethyl sulfoxide),                  b) Positive control (Mitomycin C)

c) Visible precipitation was shown at the end of exposure period

Table 2. Chromosome aberration test on CHL cells treated with 4,4’-oxybis(benzenesulfonylhydrazide) [short-term treatment: +S9 mix]

Compound

Concentration (mg/mL)

Time of exposure (hr)

Relative cell growth (%)

No. of cells analyzed

No. of cells with aberrations –gap (%)

No. of cells analyzed for polyploid

No. of polyploid cells (%)

Final Judgment

DMSOa)

0

6

100.0

200

0 (0.0)#

200

2(1.0)

 

Test substance

357

6

58.7

200

3 (1.5)*

200

3(1.5)

 

446

6

   46.9

200

6 (3.0)*

200

2(1.0)

 

557

6

18.2

200

29 (14.5)*

200

0(0.0)

Positive

696

6

4.8

Toxic

 

 

 

 

870

6

3.3

Toxic

 

 

 

 

1088

6

2.4

Toxic

 

 

 

 

CPb)

12.5

6

85.4

200

66 (33.0)*

200

1(0.5)

Positive

-gap: total number of cells with aberrations except gap

# p≤0.05: Significant difference by trend test (Cochran-Armitage trend test)

* p≤0.05: Significant difference from the negative control group (Fisher’s exact test)

a) Negative control (Dimethyl sulfoxide),                   b) Positive control (Cyclophosphamide)

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information):
positive

The genetic toxicity of OBSH was evaluated in an in vitro Mammalian chromosome aberration test on chinese hamster ling cells. The study was performed in accordance with the OECD guideline 473. OBSH exhibited clastogenic activity on cultured Chinese Hamster Lung cells.
Executive summary:

The genetic toxicity of OBSH was evaluated in an in vitro Mammalian chromosome aberration test on chinese hamster lung cells. The study was performed in accordance with the OECD guideline 473.

Significant dose-dependent increases in the proportion of cells with structural aberrations were observed in cultures both in the absence (557 to 870mg/mL) and presence (446 to 557mg/mL) metabolic activation system. Significant increases in the proportion of cells with numerical aberrations were not observed in cultures at all concentration levels.

In conclusion, OBSH exhibited clastogenic activity on cultured Chinese Hamster Lung cells both with and without S9.