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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: chromosome aberration
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1989
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Well documented, according to accepted guidelines

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1989
Report Date:
1989

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)
Version / remarks:
1983 followed, reliability scoring based on 1997 guideline.
Deviations:
no
GLP compliance:
yes
Type of assay:
micronucleus assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Isopropylchloride (2-chloro-propane)
- Physical state: Liquid (colourless)
- Storage condition of test material: Cool, well-ventilated place

Test animals

Species:
mouse
Strain:
other: BOR:NMRI SPF (Han.)
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Firma Winkelmann, Versuchtierzucht
- Age at study initiation: Adult (about 3 months)
- Weight at study initiation: 32.0 to 40.1 g (males); 29.8 to 38.4 g (females)
- Assigned to test groups randomly: Yes, by lot
- Housing: Collective caging
- Diet: Ad libitum
- Water: Ad libitum
- Acclimation period: 12 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21.5 ± 1.5
- Humidity (%): 55 ± 10
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:
intraperitoneal
Vehicle:
- Vehicle(s)/solvent(s) used: corn oil
- Amount of vehicle (if gavage or dermal): 10 mL/kg
- Lot/batch no. (if required): Batch: 2466515
- Manufacturer: Roth GmbH, Karlsruhe
Details on exposure:
PREPARATION OF DOSING SOLUTIONS: Not reported.
Duration of treatment / exposure:
Single administration
Frequency of treatment:
Single administration
Post exposure period:
24, 48, or 72 hours
Doses / concentrations
Remarks:
Doses / Concentrations:
2000 mg/kg bw
Basis:
nominal conc.
No. of animals per sex per dose:
5/sex in control groups and 15/sex in test-article groups (with 5/sex being sacrificed for smear evaluation at each time point)
Control animals:
yes, concurrent vehicle
Positive control(s):
Cyclophosphamide
- Route of administration: intraperitoneal
- Doses / concentrations: 40 mg/kg bw in 10 mL/kg corn oil

Examinations

Tissues and cell types examined:
Bone marrow from femurs.
Details of tissue and slide preparation:
The femurs were removed and the bone marrow was suspended in fetal calf serum. Samples were centrifuged at 1.600 x g, decanted and then one drop of each single suspension was smeared on a slide by means of a second slide.

These preparations were dried, fixed in absolute (99 %) methanol for 5 min. and then allowed to air dry. The slides were stained using a May-Grünwald and Giemsa solution.

From each animal 2 preparations were made. Prior to analysis all the slides were randomized and coded (blind evaluation).
Evaluation criteria:
The test substance is considered to be active if a statistically significant increase in the number of polychromatic erythrocytes with micronuclei in comparison to the control values occurs at any point in time.
Statistics:
One factorial analysis of variance.

Results and discussion

Test results
Sex:
male/female
Genotoxicity:
negative
Toxicity:
yes
Vehicle controls validity:
valid
Negative controls validity:
not applicable
Positive controls validity:
valid
Additional information on results:
RESULTS OF RANGE-FINDING STUDY
- Dose range: 1000, 2500 and 5000 mg/kg bw
- Clinical signs of toxicity in test animals:
Animals treated with 5000 and 2500 mg/kg showed severe ataxia, a distinct writhing-reflex, a lateral body position, sedation and piloerection i.e. 5 mind. p.a. and up to 4 hours p.a., whereby the lower dosed animals only showed slight ataxia, a slight sedation and a slight piloerection at this point of time. Animals treated with 1000 mg/kg were slightly sedated for about 1 hour and showed a very slight piloerection.

Any other information on results incl. tables

A very slightly reduced activity (sedation) and piloerection was noted 1 to 3 hours following administration, but the animals were normal in appearance and behaviour afterwards. No animal died throughout the study.

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information): negative