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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:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
supporting study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study
Remarks:
Comparable to guideline study without detailed documentation (publication). Read-across is justified due to the fact that the test item contains siginificant amounts of long-chain fatty alcohols (Octadecan-1-ol, CAS 112-92-5, icosan-1-ol, CAS 629-96-9 and docosan-1-ol, CAS 661-19-8). Toxicological data on Docosan-1-ol, CAS 661-19-8 is considered as representative for this set of long chain, linear fatty alcohols.

Data source

Reference
Reference Type:
review article or handbook
Title:
Unnamed
Year:
2002

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)
Deviations:
yes
Remarks:
yes (only 1000 PCEs per animal scored for micronuclei) Principles of method if other than guideline
Principles of method if other than guideline:
Study according to protocol very similar to OECD guideline 474.
GLP compliance:
not specified
Type of assay:
micronucleus assay

Test material

Constituent 1
Reference substance name:
Docosan-1-ol
EC Number:
211-546-6
EC Name:
Docosan-1-ol
Cas Number:
661-19-8
Molecular formula:
C22H46O
Constituent 2
Reference substance name:
behenyl alcohol
IUPAC Name:
behenyl alcohol
Test material form:
solid: compact
Details on test material:
- Name of test material (as cited in study report): behenyl alcohol
- Substance type: colourless, waxy solid
- Physical state: solid
- Analytical purity: no data, but for repeated dose toxicity (oral), 98%
- Impurities (identity and concentrations): no data
- Composition of test material, percentage of components: no data
- Isomers composition: no data
- Purity test date: no data
- Lot/batch No.: no data, but for repeated dose toxicity (oral), obtained from Condea, Germany
- Expiration date of the lot/batch: no data
- Stability under test conditions: no data
- Storage condition of test material: no data
- Other:
- Melting point: 70 deg C
- Soluble in: ethanol and chloroform
- Insoluble in: water

Test animals

Species:
mouse
Strain:
NMRI
Sex:
male/female
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: BRL Tierfarm Fullinsdorf, Switzerland
- Age at study initiation: >=10 weeks
- Weight at study initiation: no data
- Assigned to test groups randomly: no data
- Fasting period before study: 18 hours, but continued to receive water ad libitum
- Housing: Markrolon Type 1 cages with wire mesh tops and granulated soft wood bedding
- Diet (e.g. ad libitum): standard pellet diet, ad libitum
- Water (e.g. ad libitum): tap water, ad libitum
- Acclimation period: no data

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21
- Humidity (%): not regulated
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): 12 / 12

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
- Vehicle(s)/solvent(s) used: polyethylene glycol
- Justification for choice of solvent/vehicle: no data
- Concentration of test material in vehicle: no data [calculated: 5, 15 and 50 mg/ml]
- Amount of vehicle (if gavage or dermal): 10 ml/kg bw
- Lot/batch no. (if required): no data
- Purity: no data
Details on exposure:
PREPARATION OF DOSING SOLUTIONS: few details; test material suspended in vehicle
Duration of treatment / exposure:
single administration
Frequency of treatment:
single administration
Post exposure period:
none
Doses / concentrations
Remarks:
Doses / Concentrations:
50, 150, 500 mg/kg bw
Basis:
nominal conc.
No. of animals per sex per dose:
6
Positive control(s):
cyclophosphamide
- Justification for choice of positive control(s): no data
- Route of administration: presumably oral gavage
- Doses / concentrations: 40 mg/kg bw

Examinations

Tissues and cell types examined:
bone marrow cells
Details of tissue and slide preparation:
CRITERIA FOR DOSE SELECTION: based on previous study - 500 mg/kg bw estimated to be the "maximum attainable dose"
TREATMENT AND SAMPLING TIMES (in addition to information in specific fields): 24, 48 and 72 hours after dosing

DETAILS OF SLIDE PREPARATION: femurs removed, marrow flushed out with foetal calf serum, cell suspension centrifuged and supernatant discarded, small drop of cell pellet spread on slide, air dried, stained with May-Grunwald, mounted; 1 slide/sample

METHOD OF ANALYSIS: 1000 polychromatic erythrocytes (PCEs) scored for micronuclei; polychromatic:normochromatic (PCE:NCE) ratio scored

OTHER: only 5/sex per dose level evaluated
Evaluation criteria:
To be considered positive, either a statistically significant dose-related increase in the number of micronucleated PCEs or a reproducible, statistically significant positive response for at least one dose level.
Statistics:
Mann-Whitney test

Results and discussion

Test results
Sex:
male/female
Genotoxicity:
negative
Toxicity:
not specified
Remarks:
presumably toxic at >500 mg/kg bw
Vehicle controls validity:
valid
Negative controls validity:
not examined
Positive controls validity:
valid
Additional information on results:
RESULTS OF RANGE-FINDING STUDY
- Dose range: no data
- Solubility: no data
- Clinical signs of toxicity in test animals: no data
- Evidence of cytotoxicity in tissue analyzed: no data
- Rationale for exposure: no data
- Harvest times: no data
- High dose with and without activation: no data
- Other: presumably toxic above 500 mg/kg bw since this maximum dose was chosen for the main study on the basis of the results of the range-finding study

RESULTS OF DEFINITIVE STUDY
- Induction of micronuclei (for Micronucleus assay): 0.03-0.09% for vehicle controls, 0.04-0.10% for test material treated, 0.71% for positive control
- Ratio of PCE/NCE (for Micronucleus assay): 1.05-1.27 for vehicle controls, 0.98-1.55 for test material treated, 0.93 for positive control
- Appropriateness of dose levels and route: appropriate (top dose was apparently the maximum tolerated dose, oral route relevant to humans)
- Statistical evaluation: no statistically significant increases in the frequency of micronuclei in mice treated with the test material; statistical significance not presented for positive controlAny other information on results incl. tables

Any other information on results incl. tables

Toxicity unclear, but possibly one male and one female mouse [per group?] died either spontaneously or due to gavage error.

Table 1: Results of micronucleus assay 24 hour sampling time

Treatment

Suspending agent

Low dose

Mid dose

High dose

Concentration mg/kg bw

0

40

50

150

Harvest time

24

24

24

24

Micronucleated PCE (%)

0.03

0.71

0.07

0.08

Ratio PCE/NCE

1.27

0.93

0.98

1.07

Table 2: Results of micronucleus assay 48 hour sampling time

Treatment

Suspending agent

Test substance

Test substance

Test substance

Concentration mg/kg bw

0

50

150

500

Harvest time

48

48

48

48

Micronucleated PCE (%)

0.09

0.1

0.04

0.05

Ratio PCE/NCE

1.05

1.06

1.01

1.23

Table 3 Results of micronucleus assay 72 hour sampling time

Treatment

Suspending agent

Low dose

Mid dose

High dose

Concentration mg/kg bw

0

50

150

500

Harvest time

72

72

72

72

Micronucleated PCE (%)

0.09

0.09

0.05

0.07

Ratio PCE/NCE

1.41

1.33

1.55

1.46

PCE = polychromatic erythrocytes

NCE = normochromatic erythrocytes

Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information): negative
Executive summary:

Behenyl alcohol did not increase the incidence of micronuclei in mouse bone marrow cells after a single oral gavage dose of up to 500 mg/kg bw.