Metam-sodium

Genetic toxicity: in vivo

Administrative data

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / bone marrow chromosome aberration

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

secondary literature

Justification for type of information:

Data is from secondary source.

Data source

Reference

Reference Type:

secondary source

Title:

Genetic toxicity in vivo for Metam Sodium in Chinese hamsters using the bone marrow chromosome analysis method.

Author:

European Commission

Year:

2000

Bibliographic source:

European Commission, European Chemicals Bureau, 2000

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 475 (Mammalian Bone Marrow Chromosome Aberration Test)

Principles of method if other than guideline:

To evaluate possible clastogenicity of Metam Sodium in Chinese hamsters using the bone marrow chromosome analysis method.

GLP compliance:

not specified

Type of assay:

other: In vivo Mammalian Bone Marrow Cytogenetic Test – Chromosomal Analysis"

Test material

Test material information

Constituent 1

Reference substance name:

Metam-sodium

EC Number:

205-293-0

EC Name:

Metam-sodium

Cas Number:

137-42-8

Molecular formula:

C2H5NS2.Na

IUPAC Name:

sodium (methylcarbamothioyl)sulfanide

Test material form:

solid: crystalline

Details on test material:

- Name of test material : Metam-sodium
- Molecular formula : C2H4NNaS2
- Molecular weight : 129.1826 g/mol
- Smiles notation : C(=S)(NC)[S-].[Na+]
- InChl : 1S/C2H5NS2.Na/c1-3-2(4)5;/h1H3,(H2,3,4,5);/q;+1/p-1
- Substance type: Organic
- Physical state: Solid

Specific details on test material used for the study:

- Name of test material : Metam-sodium
- Molecular formula : C2H4NNaS2
- Molecular weight : 129.1826 g/mol
- Smiles notation : C(=S)(NC)[S-].[Na+]
- InChl : 1S/C2H5NS2.Na/c1-3-2(4)5;/h1H3,(H2,3,4,5);/q;+1/p-1
- Substance type: Organic
- Physical state: Solid

Test animals

Species:

hamster, Chinese

Strain:

other: SH (chin) Ki

Sex:

male/female

Details on test animals or test system and environmental conditions:

Not specified

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

Not specified

Details on exposure:

Not specified

Duration of treatment / exposure:

2 days

Frequency of treatment:

Single

Post exposure period:

Not specified

Doses / concentrations

Remarks:

0, 150, 300 and 600 mg/kg bw

No. of animals per sex per dose:

5/sex/group

Control animals:

yes, concurrent vehicle

Positive control(s):

Cyclophosphamide
- Route of administration: Oral gavage
- Doses / concentrations: 40 mg/kg

Examinations

Tissues and cell types examined:

bone marrow

Details of tissue and slide preparation:

Details of tissue and slide preparation
The animals were sacrificed and the bone marrow of the two femora was prepared 6, 24 and48 hours after administration of the highest dose and 24 hours after treatment of the other groups.

Evaluation criteria:

1000 metaphase cells (100/hamster) were scored for each dose level.

Statistics:

Not specified.

Results and discussion

Test results

Sex:

male/female

Genotoxicity:

negative

Toxicity:

no effects

Vehicle controls validity:

not specified

Negative controls validity:

not specified

Positive controls validity:

valid

Remarks on result:

other: No mutagenic effect were observed

Applicant's summary and conclusion

Conclusions:

Metam Sodium (137-42-8)was tested for possible clastogenicity in Chinese hamsters using the bone marrow chromosome analysis method. The test result was considered to be negative as there is no increase in the number of aberrant metaphases.

Executive summary:

In Vivo Genetic toxicity study of Metam Sodium was assessed for its possible clastogenic effect. For this purpose In vivo Mammalian Bone Marrow Cytogenetic Test – Chromosomal Analysis" was performed  according to OECD Guideline 475. The test substance was exposed to Chinese hamsters using the bone marrow chromosome analysis method. The test substance was tested in Chinese hamsters at the concentration of 0, 150, 300 and 600 mg/kg bw. The animals were sacrificed and the bone marrow of the two femora was

prepared 6, 24 and48 hours after administration of the highest dose and 24 hours after treatment of the other groups. Single oral administration of Metam Sodium in doses of 150,

300 and 600 mg/kg bw did not lead to any increase in the number of aberrant metaphases. There were no significant differences in the types and frequency of aberrations between the dose groups and the solvent control group. Therefore Metam Sodium was considered to be non mutagenic inChinese hamsters bone marrow chromosome analysis. Hence the substance cannot be classified as Gene mutant in vitro.