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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
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Study is performed in accrodance of OECD Guideline 474, and GLP and is well reportet

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2005
Report date:
2005

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)
Deviations:
not applicable
GLP compliance:
yes (incl. QA statement)
Type of assay:
micronucleus assay

Test material

Constituent 1
Chemical structure
Reference substance name:
Pentafluoroiodoethane
EC Number:
206-566-7
EC Name:
Pentafluoroiodoethane
Cas Number:
354-64-3
Molecular formula:
C2F5I
IUPAC Name:
pentafluoroiodoethane
Details on test material:
- Name of test material (as cited in study report): Pentafluorethyljodid
- Molecular weight (if other than submission substance): 246
- Physical state: gas
- Analytical purity: 98.9 %
- Vapour pressure: 1650 mbar at 20°C
- Boiling point: 11 °C
- Purity test date: n.a.
- Lot/batch No.: 26.08.2004
- Expiration date of the lot/batch: 2005-09-26

Test animals

Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Rat: HanBrl:WIST (SPF)
- Age at study initiation: 11-12 weeks
- Weight at study initiation: (m) 197.6 - 232.0 g; (f) 200.0 - 229.1 g
- Assigned to test groups randomly: yes
- Fasting period before study:
- Housing: in groups of three
- Diet (e.g. ad libitum): yes
- Water (e.g. ad libitum): yes
- Acclimation period: at least 5 days
- Photoperiod (hrs dark / hrs light): 12 hour dark period/12 artificial fluorescent light

Administration / exposure

Route of administration:
inhalation: gas
Vehicle:
air
Details on exposure:
nose only exposure,
positive controls received respective item orally
Duration of treatment / exposure:
4 hour; nose only
Frequency of treatment:
one single exposure per dose group
Post exposure period:
24 hours for
air control: Air
low dose: 12.500 ppm Pentafluoroethyljodid
medium dose: 25.000 ppm Pentafluoroethyljodid
high group; 50.000 ppm Pentafluoroethyljodid
positive control: 40 mg/kg bw CPA (oral)
48 hours for:
high dose group: 50.00 ppm Pentafluoroethyljodid
Doses / concentrations
Remarks:
Doses / Concentrations:
air, 12500, 25.000 and 50.000 ppm Pentafluoethyljodide, positive control CPA 40mg/kg bw
Basis:
nominal conc.
No. of animals per sex per dose:
6 animals/sex/dose
Control animals:
yes, concurrent vehicle
Positive control(s):
cyclophosphamide (CPA)
- Justification for choice of positive control(s): not mentioned
- Route of administration: oral
- Doses / concentrations: 40 mg/kg bw

Examinations

Tissues and cell types examined:
Bone marrow, erythroblasts

Results and discussion

Test results
Sex:
male/female
Genotoxicity:
negative
Remarks:
The mean values of micronuclei observed after treatment with the test item were below or near to the value of the air control group.
Toxicity:
no effects
Vehicle controls validity:
valid
Positive controls validity:
valid

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information): negative
In conlusion, it can be stated that during the study described and under the experimental conditions reported, the test item did not induce micronuclei as determined by the micronucleus test in the bone marrow cells of the rat. Therefore, the test item is considered to be non-mutagenic in this micronucleus assay.
Executive summary:

The study was performed to investigate the potential of the test substance to induce micronuclei in polychromatic erythrocytes (PCE) in the bone marrow of the rat. Ten animals (5/sex) per test group were evaluated for the occurrence of micronuclei. The test item doses administered by inhalation were 12500ppm, 25000 ppm and 50000 ppm. Air was used as control. The highest dose (50000 ppm) was estimated by pre-experiment to be suitable. 24 h and 48 h after the administration of the test item the bone marrow cells were collected for micronuclei analysis. At least 2000 polychromatic erythrocytes (PCEs) per animal were scored for micronuclei. To describe a cytotoxic effect due to the treatment with the test item the ratio between polychromatic and total erythrocytes was determined in the sample and recorded as the number of PCEs per 2000 erythrocytes. In the main study 1 male died after treatment with the high dose (50000 ppm). After treatment with the test item the number of PCEs was not substantially decreased as compared to the mean value of PCEs of the vehicle control air thus indicating that the test substance did not exert any cytotoxic effects to the bone marrow of the rat. In comparison to the corresponding vehicle controls there was no biologically relevant or statistically significant enhancement in the frequency of the detected micronuclei at any preparation interval after administration of the test item and with any dose level used. 40 mg/kg bw cyclophosphamide administered orally was used as positive control which showed a substantial increase of induced micronucleus frequency.

In conclusion, it can be stated that during the study described and under the experimental conditions reported, the test item did not induce micronuclei as determined by the micronucleus test in the bone marrow cells of the rat. Therefore, the test item is considered to be non-mutagenic in this micronucleus assay.