2-methyl-4-phenylpentanol

Genetic toxicity: in vivo

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:

25 Auqust 1987 and 18 September 1987

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted in accordance with OECD guidelines and in compliance with GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

Deviations:

no

GLP compliance:

yes

Type of assay:

micronucleus assay

Test material

Test material information

Constituent 1

Reference substance name:

Pamplefleur

IUPAC Name:

Pamplefleur

Test material form:

other: clear liquid

Details on test material:

Identity: Pamplefleur.
Chemical name (IUPAC): l-pentanol, 2-methyl-4-phenyl.
Purity: >99%
Description: Clear liquid.
Storaqe: Room temperature in the dark.
Solubility: Insoluble in water.

Emulsions of Pamplefleur was prepared in aqueous 1% methylcellulose (obtained from British Celanese Ltd.) at the concentrations shown overleaf usinq a Silverson hiqh-speed mixer.

Test animals

Species:

mouse

Strain:

CD-1

Sex:

male/female

Details on test animals or test system and environmental conditions:

All animals in this study were Specific Pathogen Free CD-1 outbred mice of Swiss origin weighing between 22 and 24 grams and approximately 35 days old, on despatch. The animals were obtained from Charles River U.K. Limited, Marqate, Kent, England on 21st Auqust 1987, 28th Auqust 1987 (preliminary to phases 1 and 2) and 4 September 1987 (main micronucleus test). On arrival, the weight of the animals was checked, the animals were randomly assigned to groups, and tail marked. Each group of 2 or 5 mice was kept in a plastic disposable cage and maintained in a controlled environment with 30 changes of air per hour and the thermostat set at 22degC. The room was illuminated by artificial light for 12 hours per day. All animals were allowed free access to pelleted Labsure LAD 1 rodent breedinq diet and tap water. They were acclimatised for approximately four days, examined daily for signs of reaction and were weighed prior to dosing.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

Aqueous 1% methylcellulose (obtained from British Celanese Ltd.)

Details on exposure:

From the results obtained in the preliminary toxicity study, a dosage of 871 mq per kg bodyweiqht was chosen for the micronucleus test. Forty male and forty female mice were used in this part of the study.

Duration of treatment / exposure:

Followinq dosing the animals were examined reqularly, and any mortalities or clinical signs of reaction to the test compounds were recorded. Five males and five females from the negative control and test compound groups were sacrificed 24, 48 and 72 hours after dosing. The positive control group was sacrificed 24 hours after dosing.

Frequency of treatment:

Once only.

Post exposure period:

24, 48 or 72 hours.

Doses / concentrations

Remarks:

Doses / Concentrations:
Indicate the dose or concentration levels applied and the basis of quantity used.
Basis:
other: Pamplefleur was formulated at 43.55 mg/ml and dosed at 10 ml/kg to give 871 mg/kg.

No. of animals per sex per dose:

Thirty-two male and thirty-two female mice were used in the preliminary toxicity test.

Forty male and forty female mice were used in the micronucleus test.

Control animals:

other: Five males and five females from the negative control groups were sacrificed 24, 48 and 72 hours after dosing.

Positive control(s):

Mitomycin C, obtained from Siqma London Chemical Company Limited (batch number 96F-0547-1), was used as the positive control compound. It was prepared as a solution in sterile 0.9% saline at a concentration of 0.6 mq/ml.

Examinations

Tissues and cell types examined:

Bone marrow, polychromatic and normochromatic erythrocytes.

Details of tissue and slide preparation:

The animals were killed by cervical dislocation and both femurs dissected out from each animal. The femurs were cleared of tissue and one epiphysis removed from each bone.· A direct bone marrow smear was made onto a slide containing a drop of calf serum. One smear was made from each femur. The prepared smears were air-dried and fixed in methanol.

After fixation, the smears were air-dried and stained in Giemsa. After rinsinq in buffered distilled water (pH.6. 8), the slides were air-dried and mounted with coverslips using DPX.

The stained smears were examined (under code) by light microscopy to determine the incidence of micronucleated cells per 1000 polychromatic erythrocytes per animal. The ratio of polychromatic to normochromatic erythrocytes for each animal was assessed by examination of at least1000 erythrocytes. A record of the number of micronucleated normochromatic erythrocytes was also kept as recommended by Schmid.

Evaluation criteria:

Evaluated for statistically significant increases in micronuleated erythrocytes.

Statistics:

Wilcoxon's sum of ranks test was used.

Results and discussion

Test results

Sex:

male/female

Genotoxicity:

negative

Toxicity:

yes

Remarks:

Clinical signs observed.

Vehicle controls validity:

valid

Negative controls validity:

not applicable

Positive controls validity:

valid

Any other information on results incl. tables

Preliminary toxicity test

From the results of the preliminary toxicity test, a dosage value of 871 mg/kg was calculated using probit analysis. This dosage was chosen for use in the main test.

Micronucleus test

Signs and mortalities

No animals died in the main study.

Micronucleated polychromatic erythrocyte counts (mnp)

Pamplefleur did not cause any statistically significant increases in the number of micronucleated polychromatic erythrocytes at any of the three kill times - P>O.O5 using Wilcoxon's sum of ranks test.

Micronucleated normochromatic erythrocytes (mnn)

Pamplefleur did not cause any substantial increases in the incidence of micronucleated normochromatic erythrocytes at any of the three kill times.

Ratio of polychromatic to normochromatic erythrocytes (p/n)

Pamplefleur failed to cause any significant decreases in the ratio of polychromatic to normochromatic erythrocytes P>O.O5 using Wilcoxon's sum of ranks test. Mitomycin C caused statistically significant decreases in the ratio (P<0.01).

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): negative
From the results obtained it is concluded that Pamplefleur shows no evidence of mutagenic potential or bone marrow cell toxicity when administered orally in this in vivo test procedure.

Executive summary:

An in vivo micronucleus test was performed according to OECD TG 474. In this assessment of the effect of Pamplefleur on the incidence of micronucleated polychromatic erythrocytes in mice, a dosage of 871 mq/kg bodyweiqht was administered orally, by lntraqastric gavage. (A preliminary toxicity test had been carried out to determine the toxicity of Pamplefleur and this dosage was approximately the expected LD10/3d).

Negative and positive control groups were dosed in an identical manner, orally by intragastric gavage. The negative control group received the vehicle, 1% methylcellulose. The positive control group was treated with mitomycin C, at 12 mg/kg.

Bone marrow smears were obtained from the negative control and test compound qroups at 3 sampling times, these being 24, 48 or 72 hours after dosing. Bone marrow smears were obtained from the positive control group 24 hours after dosing. One smear from each animal was examined for the presence of micronuclei in 1000 polychromatic erythrocytes. The ratio of polychromatic to normochromatic erythrocytes was assessed by examination of at least 1000 erythrocytes from each animal. A record of the incidence of micronucleated normochromatic erythrocytes was also kept.

At all sampling times, mice treated with Pamplefleur showed no significant increase in the frequency of micronucleated polychromatic erythrocytes.

There was no siqnificant decrease in the ratio of polychromatic to normochromatic erythrocytes after treatment of the animals with Pamplefleur.

The positive control compound, mitomycin C, produced large, highly significant increases in the frequency of micronucleated polychromatic erythrocytes together with decreases in the ratio of polychromatic to normochromatic erythrocyte.

It is concluded from the results obtained that Pamplefleur shows no evidence of mutagenic potential or bone marrow cell toxicity when administered orally in this in vivo test procedure.