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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
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
1992
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study with acceptable restrictions

Data source

Reference
Reference Type:
publication
Title:
Unnamed
Year:
2006
Report Date:
2006

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)
Deviations:
not specified
GLP compliance:
yes
Type of assay:
other: mammalian erythrocyte micronucleus test (migrated information)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: crystalline

Test animals

Species:
mouse
Strain:
other: Albino mice CFW 1
Sex:
male/female
Details on test animals and environmental conditions:
Test organisms: Mouse CFW 1
- Age: 7-8 weeks
- Weight at study initiation: males 21-27g, females 21-26g

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
Arachis oil
Duration of treatment / exposure:
1 d, single administration
Frequency of treatment:
Once
Post exposure period:
Sampling times and number of samples: 24, 48 and 72 h after treatment. Two slides were prepared for each animal and 1000 polychromatic erythrocytes (PCE) scored.
Doses / concentrations
Dose / conc.:
5 000 mg/kg bw/day
No. of animals per sex per dose:
6 animals per sex per dose
Control animals:
yes, concurrent vehicle
Positive control(s):
Cyclophosphamide 20 mg/kg bw

Examinations

Tissues and cell types examined:
- Clinical observations: Daily
- Organs examined at necropsy: None
- Criteria for selection of M.T.D.: Based on a screening test. Effects seen at 5000 mg/kg were piloerection only
Evaluation criteria:
- Criteria for evaluating results: A statistically significant (p<0.05) increase in Polychromatic erythrocytes (PCE) compared to controls
- Method used: Kastenbaum & Bowman

Results and discussion

Test results
Key result
Sex:
male/female
Genotoxicity:
negative
Toxicity:
no effects
Vehicle controls validity:
not specified
Negative controls validity:
not specified
Positive controls validity:
not specified
Additional information on results:
No statistically significant increase in micronucleated polychromatic erythrocytes compared to vehicle controls, the positive control group did produce a statistically significant increase.

Any other information on results incl. tables

Results

Mortality

None

Clinical signs

Piloerection in all test animals.

PCE/NCE ratio

There was no effect on this ratio.

Genotoxic effects

There was no increase in the incidence of micronucleated cells in the test group. The incidence of micronuclei in the contorl group was within historical control ranges. The positive control group produced an appropriate increase in numbers of micronucleated cells.

Applicant's summary and conclusion

Conclusions:
Under the study conditions, the test substance was determined to be non-clastogenic in the micronuleus assay in mice.
Executive summary:

An in vivo study was conducted to determine the genotoxic potential of the test substance, 1-dodecanol (purity not specified) in mice, according to OECD Guideline 474 (Micronucleus test), in compliance with GLP. In this study, 12 mice (6 per sex) per dose, were administered single dose of each, test substance (5000 mg/kg bw dodecanol in arachis oil), positive control (Cyclophosphamide 20 mg/kg bw) and solvent control (Arachis oil) substances at 10 mL/kg bw dose, by oral gavage. The maximum tolerated dose (MTD) of 5000 mg/kg bw was determined in a screening test. Samples of blood were collected and analysed 24, 48 and 72 h after treatment period. Two slides were prepared for each animal and 1000 polychromatic erythrocytes (PCE) scored. A statistically significant (p<0.05) increase in PCE compared to normochromatic erythrocytes (NCE) was examined by Kastenbaum & Bowman method. Clinical examination was performed daily. No mortality was observed during the study. Only reported clinical sign was piloerection in all animals. There was no increase in the incidence of micronucleated cells in the test group. The incidence of micronuclei in the control group was within historical control ranges. The positive control group produced an appropriate increase in numbers of micronucleated cells. No statistically significant increase in micronucleated polychromatic erythrocytes in mice was observed at any time interval after treatment (24, 48 or 72 h) at dose levels up to 5000 mg/kg bw when compared to vehicle controls (PCE/NCE ratio), whereas the positive control group did produce a statistically significant increase. The study had met all the validity criteria required for the test. Under the study conditions, the test substance was concluded to be non-clastogenic in the micronuleus assay in mice (OECD SIDS, 2006).