Methyl 3-[3-(2H-benzotriazol-2-yl)-4-hydroxy-5-(2-methyl-2-propanyl)phenyl]propanoate

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:

1985

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP-compliant study, similar to OECD testing guideline.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1985

Report date:

1985

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

Deviations:

yes

Remarks:

Only 1000 cells per dose group scored.

GLP compliance:

yes

Remarks:

Genetic Toxicology, CIBA-GEIGY Ltd., Basle, Switzerland

Type of assay:

other: Nucleus Anomaly Test

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

400-820-2

EC Name:

-

Cas Number:

84268-33-7

Molecular formula:

C20 H23 N3 O3

IUPAC Name:

methyl 3-[3-(2H-1,2,3-benzotriazol-2-yl)-5-tert-butyl-4-hydroxyphenyl]propanoate

Details on test material:

- Physical state: solid
- Analytical purity: purified
- Lot/batch No.: Z 288/1U

Test animals

Species:

hamster, Chinese

Strain:

not specified

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: 4 - 9 weeks
- Weight at study initiation: female: 21-29 g, male: 21-32 g
- Assigned to test groups randomly: [no/yes, under following basis: ]
- Fasting period before study:
- Housing:
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period:

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 23-24
- Humidity (%): 56 - 58
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

- Vehicle(s)/solvent(s) used: 0.5% aqueous solution of sodium-carboxylmethylcellulose + 0.1% Tween 80

Duration of treatment / exposure:

2 days

Frequency of treatment:

daily

Post exposure period:

24 hours

Doses / concentrations

Remarks:

Doses / Concentrations:
560, 1120, 2240 mg/kg
Basis:
actual ingested

No. of animals per sex per dose:

6

Control animals:

yes, concurrent vehicle

Positive control(s):

cyclophosphamide
- Route of administration: oral gavage
- Doses / concentrations: 128 mg/kg bw / 20mL/kg

Examinations

Tissues and cell types examined:

bone marrow

Details of tissue and slide preparation:

DETAILS OF SLIDE PREPARATION: Small drops of the mixture were transferred on the end of a slide, spread out by pulling it behind a polished cover glass and the preparations were air-dried. Three hours later, the slides were stained in undiluted May-Gruenwald solution for 2 min then in May-Gruenwald solution/water 1/1 for 2 min and then in Giemsa's, 40% for 20 min. After being rinsed in methanol 55% for 5-8 sec and washed off twice in water,
they were left immersed in water for approx. 2 min. After rinsing with distilled water and air-drying, the slides were cleared in Xylene and mounted in Eukitt.

METHOD OF ANALYSIS: The slides of three female and three male animals each of the negative control group, the positive control group and of the groups treated with various doses were examined, 1000 bone marrow cells each were scored per animal and the following anomalies were
registered:
a) Single Jolly bodies, b) fragments of nuclei in erythrocytes, c) micronuclei in erythroblasts, d) micronuclei in leucopoietic cells, e) polyploid cells,

Evaluation criteria:

1,000 Bone marrow cells were scored from each animals and the following anomalies were registered:

a) Single Jolly bodies,
b) fragments of nuclei in erythrocytes,
c) micronuclei in erythroblasts,
d) micronuclei in leucopoietic cells,
e) bizarre forms of nuclei,
f) polyploid cells and
g) necrobiotic cells

Statistics:

The significance of difference was assessed by chi-square-test.

Results and discussion

Test results

Sex:

male/female

Genotoxicity:

negative

Toxicity:

no effects

Vehicle controls validity:

valid

Negative controls validity:

not examined

Positive controls validity:

valid

Additional information on results:

RESULTS OF DEFINITIVE STUDY
One female animal of the positive control group died in the course of the experiment.
The bone marrow smears from animals treated with the various doses showed no significant difference from the control. The incidence of bone marrow cells with anomalies of nuclei corresponds to the frequency observed in the control group.
By contrast, a "positive control" experiment with cyclophosphamide (128 mg/kg) yielded 9,87% cells with anomalies of nuclei. This is significantly different from the controls (0,15%) treated with the vehicle (0,5% CMC +0,1% Tween 80) alone (see attached table)

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): negative