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Toxicological information

Genetic toxicity: in vivo

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Administrative data

Endpoint:
in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus
Remarks:
Type of genotoxicity: other: damage of chromosomes or mitotic apparatus
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Important aspects are in line with current OECD guidelines

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1980
Report date:
1980

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)
Deviations:
not specified
GLP compliance:
yes
Type of assay:
micronucleus assay

Test material

Constituent 1
Chemical structure
Reference substance name:
o-phenylenediamine
EC Number:
202-430-6
EC Name:
o-phenylenediamine
Cas Number:
95-54-5
Molecular formula:
C6H8N2
IUPAC Name:
benzene-1,2-diamine
Details on test material:
- Name of test material (as cited in study report): Hoe 37197 O T AT201 (o-Phenylendiamin)

Test animals

Species:
mouse
Strain:
other: NMRI strain Hoe NMRKf (SPF71)
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Pharma Forschung Toxikologie, Kastengrund, Hattersheim, Germany
- Age at study initiation: 10-12 weeks
- Weight at study initiation: male: 32 - 40 g, female: 23 - 29 g
- Assigned to test groups randomly: yes
- Fasting period before study: no fasting period
- Housing: plastic cages, groups of five, same-sex
- Diet ad libitum: yes
- Water ad libitum: yes
- Acclimation period: not specified

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
Deionised water for the test substance and aqua dest. for the positive control
Details on exposure:
PREPARATION OF DOSING SOLUTIONS:

DOSE PREPARATION
- Rate of preparation: daily before application,
- Stock solution: 1250 mg test substance ad 50 ml
- Dose concentrations: dilutions of stock solution
Duration of treatment / exposure:
In a range finder test 250 mg/kg bw. was found to be the max. tolerable dose.
Two applications at 24 hours intervals. 6 hours after the second application the animals were killed.
Frequency of treatment:
Two applications at 24 hours intervals.
Post exposure period:
6 hours after the second application the animals were killed.
Doses / concentrations
Remarks:
Doses / Concentrations:
0; 2.5; 25; and 250 mg/kg bw.
Basis:
other: nominal dose administered
No. of animals per sex per dose:
5 male and 5 female mice
Control animals:
yes, concurrent no treatment
Positive control(s):
Cyclophophamid (Endoxan, Edoxan W.Z. of company Asta, Brackwede): 100 mg/kg bw

Examinations

Tissues and cell types examined:
bone marrow erythroctes
Details of tissue and slide preparation:
Cells are removed from femures and poured in 5 ml of fetal calf's serum. The mixture was centrifuged at 1000 RPM. One drop of the cell suspension was spread on an object slide and dried for 24h at room temperature. Staining was done using May-Grünwaldt- and Giesema-solution.
Evaluation criteria:
2000 polychromatic erythorcytes were examined for micronuclei containing cells. Additionally 1000 monochromatic erythrocytes were examined for micronuclei containing cells.
Statistics:
Binomial distribution, for increase, 90% confidence interval
Nemeny / Dunnett, deviation from control, 95% confidence interval

Results and discussion

Test results
Sex:
male/female
Genotoxicity:
positive
Remarks:
at 250 mg/kg bw
Toxicity:
yes
Remarks:
>250 mg/kg bw
Vehicle controls validity:
not examined
Negative controls validity:
valid
Positive controls validity:
valid
Additional information on results:
RESULTS OF DEFINITIVE STUDY
- Induction of micronuclei (for Micronucleus assay): significant increase at 250 mg/kg, no effects at lower doses
- Ratio of PCE/NCE (for Micronucleus assay): uneffected

Any other information on results incl. tables

Dose

mg/kg

Animal No

MN per 2000 PCE

MN per 1000 NCE

Ratio of PCE/NCE

 

m

f

m

f

m

f

m

f

Control

1

6

4

4

2

3

778

:

1000

1231

:

1000

2

7

5

14

1

1

1082

:

1000

1210

:

1000

3

8

16

8

3

1

975

:

1000

1161

:

1000

4

9

16

9

1

1

1102

:

1000

1019

:

1000

5

10

15

3

0

1

972

:

1000

1115

:

1000

2.5

11

16

14

7

1

0

972

:

1000

1199

:

1000

12

17

3

12

1

2

952

:

1000

1148

:

1000

13

18

9

6

2

2

1175

:

1000

1291

:

1000

14

19

11

11

2

1

1023

:

1000

1087

:

1000

15

20

7

6

1

1

868

:

1000

981

:

1000

25.0

21

26

10

6

1

0

914

:

1000

1060

:

1000

22

27

6

14

0

0

1093

:

1000

1107

:

1000

23

28

9

6

0

2

1168

:

1000

1115

:

1000

24

29

9

5

2

0

1011

:

1000

977

:

1000

25

30

11

15

1

1

1053

:

1000

1147

:

1000

250.0

31

36

24

23

1

0

781

:

1000

1133

:

1000

32

37

23

25

0

0

823

:

1000

557

:

1000

33

37

27

20

1

1

928

:

1000

778

:

1000

34

39

28

19

2

1

100

:

1000

814

:

1000

35

40

22

20

0

0

826

:

1000

856

:

1000

100.0 Cyclophosphamid

41

46

147

93

3

1

863

:

1000

758

:

1000

42

47

152

107

1

1

511

:

1000

600

:

1000

43

48

108

139

2

2

542

:

1000

586

:

1000

44

49

105

136

1

2

567

:

1000

459

:

1000

45

50

129

158

1

3

535

:

1000

629

:

1000

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information): positive
Significant increase of micronucleated polychromatic erythrocytes at the highest dose level tested (250 mg/kg) in male an female mice.

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