Registration Dossier

Toxicological information

Genetic toxicity: in vivo

Currently viewing:

Administrative data

Endpoint:
in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus
Remarks:
Type of genotoxicity: chromosome aberration
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1990
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP - Guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1990
Report date:
1990

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)
Deviations:
no
GLP compliance:
yes
Type of assay:
micronucleus assay

Test material

Constituent 1
Chemical structure
Reference substance name:
1-chloro-4-nitrobenzene
EC Number:
202-809-6
EC Name:
1-chloro-4-nitrobenzene
Cas Number:
100-00-5
Molecular formula:
C6H4ClNO2
IUPAC Name:
1-chloro-4-nitrobenzene
Details on test material:
- Name of test material (as cited in study report): p-Nitrochlorbenzene
- Analytical purity: 99.40 %
- Impurities (identity and concentrations): 0.19 % m-Nitrochlorbenzene and 0.37 % o-Nitrochlorbenzene
- Purity test date: 1980-06-20
- BALK Order No.: 88/126B
- Expiration date of the lot/batch: 1989-02-02
- Product No.: 039772
- Sample No.: 836093/1989

Test animals

Species:
mouse
Strain:
NMRI
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Winkelmann, Borchen, Germany
- Weight at study initiation: 29 - 45 g
- Age at study initiation : 8 - 12 weeks
- Housing: females: one to three mice in Makrolon type I and II cages
males: single housing in type I cages
- Diet (e.g. ad libitum): Altromin Standard Diet, Altromin GmbH, Lage, Germany
- Water: ad libitum
- Acclimation period: 1 week


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21.5 - 23°C
- Humidity (%): 43 - 49 %
- Air changes (per hr): 10 times per hour
- Photoperiod (hrs dark / hrs light): 12 hours electric lighting daily (6.00 - 18.00)


Administration / exposure

Route of administration:
intraperitoneal
Vehicle:
corn oil
Duration of treatment / exposure:
single application
Frequency of treatment:
24, 48, 72 hours 
Post exposure period:
no data
Doses / concentrations
Remarks:
Doses / Concentrations:
0, 500 mg/kg bw
Basis:
other: dissolved in corn oil based on a range finding study (100, 500, 750, 1000 mg/kg bw)
No. of animals per sex per dose:
5
Control animals:
yes, concurrent vehicle
Positive control(s):
cyclophosphamide in form of Endoxan (batch No.: 098491)
- Justification for choice of positive control(s):
- Route of administration: intraperitoneal
- Doses / concentrations: 10 ml/kg bw

Examinations

Tissues and cell types examined:
Femoral bone marrow of the lower-leg stump (including the knee)
Details of tissue and slide preparation:
CRITERIA FOR DOSE SELECTION:
Dose was based on a pilot test, in which groups of 5 animals, icluding females and males, were intraperitoneally administered 100 mg/kg, 250 mg/kg, 500 mg/kg, 750 mg/kg (2 groups) and 1000 mg/kg p-nitrochlorobenzene.

DETAILS OF SLIDE PREPARATION:
Schmidt´s method was used to produce the smears.
Smears were stained with Ames HemaTek Slide Stainer from the Miles Company. The slide were then destained with methanol, rinsed with deionized water and left to dry.

METHOD OF ANALYSIS:
Coded slides were evaluated using a light microscope at a magnification of about 1000. Micronuclei appear as stained chromatin particles in the anucleated erythrocytes. The number of normochromatic erythrocytes per 1000 polychromatic was noted.




Evaluation criteria:
A test was considered positive if, at any of the intervals, there was a relevant and significant increase in the number of polychromatic erythrocytes showing micronuclei in comparison to the negative control.
Statistics:
Wilcoxon's non-parametric rank sum test, one-sided chi-square-test

Results and discussion

Test results
Sex:
male/female
Genotoxicity:
positive
Toxicity:
not examined
Vehicle controls validity:
valid
Negative controls validity:
valid
Positive controls validity:
valid

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information): positive
Executive summary:
Herbold, Bayer AG, 1990

A micronucleus assay in mouse bone marrow was performed according to OECD guideline 474. A single intraperitoneal application of 500 mg/kg body weight induced a positive effect. Treated animals showed lasting symptoms of toxicity after administration (apathy, sounds, roughened fur, cyanosis, spasm, staggering gait, twitching, shivery, difficulty in breathing), the ratio of polychromatic to normochromatic erythrocytes was altered by treatment with p-chloro-nitrobenzene.