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Toxicological information

Genetic toxicity: in vivo

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Administrative data

Endpoint:
in vivo mammalian germ cell study: cytogenicity / chromosome aberration
Remarks:
Type of genotoxicity: chromosome aberration
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
limited but acceptable documented publication which meets basic scientific principles; however study design not in line with current guidelines (e.g. sampling time 1.5 normal cell cylce lengh, preparation time after colcemid or colchicine application ca. 3 to 5 h for mice, 5 animals per sex and dose group, measure of cytotoxicity)

Data source

Reference
Reference Type:
publication
Title:
Assessment of in vivo chromosomal aberrations - potency of zinc mercapto benzo thiazole
Author:
Mohanan, P., V.; et al.
Year:
2000
Bibliographic source:
Journal of Biomaterials Aplcations, volume 14,224-228

Materials and methods

Principles of method if other than guideline:
other: chromosomal aberration assay in Swiss albino mice
GLP compliance:
no
Type of assay:
chromosome aberration assay

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
zinc mercapto benzo thiazole (ZMBT)

Test animals

Species:
mouse
Strain:
Swiss
Sex:
not specified

Administration / exposure

Route of administration:
intraperitoneal
Duration of treatment / exposure:
once
Frequency of treatment:
once
Post exposure period:
36 h
Doses / concentrations
Remarks:
Doses / Concentrations:
0, 480 µg, 860 µg, 1920 µg/20g animal (ca. 0, 24, 43, 96 mg/kg bw)
Basis:

No. of animals per sex per dose:
4 per dose
Control animals:
yes, concurrent vehicle

Examinations

Tissues and cell types examined:
bone marrow from femur

Results and discussion

Test results
Sex:
not specified
Genotoxicity:
negative
Toxicity:
not examined
Vehicle controls validity:
valid
Negative controls validity:
not examined
Positive controls validity:
valid

Any other information on results incl. tables

Chromosome number: number of chromosomes did not vary (no additional data)

The incidences of chromosome/chromatide abnormalities was comparable between treamtent groups and solvent control.

The postivie control induced significant number of chromosomal aberrations.

The authors conclude that the administration of ZMBT at different dose levels in Swiss mice did not increase the frequency of structural chromosomal aberrations and thus ZMBT did not induce structural chromosome aberrations in the bone marrow cells of Swiss mice under the experimental conditions used.

Table: Incidence of chromosomal aberrations after single ZMBT administration in the bone marrow of Swiss mice

              Average Abnormalities/100 plates  
        Chromatid*   Chromosome*  
 Group  Dose/animal (µg)  Gaps  Breaks  Gaps  Breaks  Other changes*
 I  1920  2  0  1  0  5
 II  960  1  1  0  0  3
 III  480  1  0  0  0  5
 IV  solvent control 1.0 ml  2  1  1  0  7
 V  positive control 4.0 mg  17  6  11  8  19

* no additional data recorded

Applicant's summary and conclusion