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Diss Factsheets

Administrative data

Endpoint:
in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus
Type of information:
experimental study
Adequacy of study:
key study
Study period:
August 1984 to February 1985
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1985
Report date:
1985

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)
Deviations:
no
GLP compliance:
yes
Type of assay:
mammalian erythrocyte micronucleus test

Test material

Constituent 1
Chemical structure
Reference substance name:
4-(trifluoromethoxy)aniline
EC Number:
207-317-5
EC Name:
4-(trifluoromethoxy)aniline
Cas Number:
461-82-5
Molecular formula:
C7H6F3NO
IUPAC Name:
4-(trifluoromethoxy)aniline

Test animals

Species:
mouse
Strain:
other:
Remarks:
NMRI
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: F. Winkelmann, Borchen, Germany
- Age at study initiation: 8-12 weeks
- Weight at study initiation: 26-38 g
- Assigned to test groups randomly: yes
- Fasting period before study: no
- Housing: Housed 3-5 mice per cage by sex and test group in Makrolon cages type I or Type II
- Diet: Altromin 1324 (Altromin GmbH, Lage, Germany), ad libitum
- Water: tap water ad libitum
- Acclimation period: minimum of one week

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 24-26
- Humidity (%): 72-85
- Air changes (per hr): not reported
- Photoperiod (hrs dark / hrs light): 12 hours electric lighting

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
- Vehicle(s)/solvent(s) used: peanut oil
- Amount of vehicle (if gavage or dermal): 5 mL/kg bw
Details on exposure:
the test item was dissolved in peanut oil and given orally by gavage; no further details are available
Duration of treatment / exposure:
not applicable since single oral application by gavage
Frequency of treatment:
single exposure
Post exposure period:
24, 48, and 72 hours post exposure
Doses / concentrations
Dose / conc.:
66 mg/kg bw/day
No. of animals per sex per dose:
5 males and 5 females
Control animals:
yes, concurrent vehicle
Positive control(s):
Endoxan dissolved in demineralized water
- Justification for choice of positive control(s): known as mutagen and cytostatic
- Route of administration: orally
- Doses / concentrations: 29 mg/kg bw or equivalent to 20 mg/kg bw in relation to the active ingredient cyclophosphamide

Examinations

Tissues and cell types examined:
Femoral marrow smears were prepared according to the method of Schmid (1975) and polychromatic erythrocytes (PCE's) were examined for micronuclei.
Details of tissue and slide preparation:
CRITERIA FOR DOSE SELECTION: Doses were based on a pilot study, in which groups of 5 animals were orally administered 0.05 mL/kg, 0.075 mL/kg and 0.1 mL/kg test substance. Doses of 0.05 mL/kg were tolerated with cyanosis and somnolence, while 2/5 animals died after being administered 0.075 mL/kg. Three out of 5 animals administered 0.1 mL/kg died.

TREATMENT AND SAMPLING TIMES Animals were administered the test material once. At times of 24, 48, and 72 hours after administration, the animals were sacrificed by decapitation and the femoral marrow smears were prepared. Smears from the negative and positive controls were produced only after 24 hours.

METHOD OF ANALYSIS: A minimum of 1000 PCE's were examined microscopically for each animal per sample time. The PCE/normochromatic erythrocyte (NCE) ratio for approximately 1000 total cells was calculated and recorded. The number of micronucleated PCE/1000 NCE was recorded.
Evaluation criteria:
A test result is considered to be negative if no statistically significant or dose related increases are apparent between the vehicle control and groups of treated animals.
Statistics:
The highest values in the treated animals and positive controls were statistically evaluated with Wilcoxon's non-parametric rank sum test.

Results and discussion

Test results
Key result
Sex:
male/female
Genotoxicity:
negative
Toxicity:
yes
Remarks:
cyanosis lasting up to 6 hours
Vehicle controls validity:
valid
Negative controls validity:
not examined
Positive controls validity:
valid

Applicant's summary and conclusion

Conclusions:
In a study conducted in a similar manner to OECD 474, there were no indications of a clastogenic effect after mice were treated with 0.05 mL/kg bw of 4-trifluoromethoxyaniline, corresponding to a dose level of 66 mg/kg bw (conversion based on density 1.32 g/mm3).