Thiosemicarbazide

Genetic toxicity: in vitro

Administrative data

Endpoint:

in vitro gene mutation study in bacteria

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1978

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 471 (Bacterial Reverse Mutation Assay)

Deviations:

no

Principles of method if other than guideline:

Ames et al.

GLP compliance:

not specified

Type of assay:

bacterial reverse mutation assay

Test material

Test material information

Constituent 1

Reference substance name:

Thiosemicarbazide

EC Number:

201-184-7

EC Name:

Thiosemicarbazide

Cas Number:

79-19-6

Molecular formula:

CH5N3S

IUPAC Name:

hydrazinecarbothioamide

Test material form:

solid: crystalline

Method

Target gene:

Histidine-requiring gene

Species / strain

Species / strain 1

Species / strain / cell type:

S. typhimurium TA 1535

Species / strain 2

Species / strain / cell type:

S. typhimurium TA 98

Species / strain 3

Species / strain / cell type:

S. typhimurium TA 100

Metabolic activation:

with and without

Test concentrations with justification for top dose:

1,600, 1,200, 800, 400, 200, 100 μg / 0.1 ml / Plate

Vehicle / solvent:

- Vehicle(s)/solvent(s) used: water

Details on test system and experimental conditions:

METHOD OF APPLICATION: in agar (plate incorporation).

DURATION
- Preincubation period:20 min
- Exposure duration:48 hours, 37ºC

Results and discussion

Test results

Test results 1

Key result

Species / strain:

S. typhimurium TA 1535

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Test results 2

Key result

Species / strain:

S. typhimurium TA 98

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Test results 3

Key result

Species / strain:

S. typhimurium TA 100

Metabolic activation:

with and without

Genotoxicity:

negative

Cytotoxicity / choice of top concentrations:

not specified

Applicant's summary and conclusion

Conclusions:

The test substance thiosemicarabzide was not mutagenic in the strains TA100; TA1535 and TA98 of S. typhimurium with and without metabolic activation.

Executive summary:

A bacterial mutagenicity assay was performed for the test item Thiosemicarbazide in strains TA100, TA1535 and TA98 of S. typhimurium. The test item dilutions were prepared in water: 1,600, 1,200, 800, 400, 200, 100 μg / 0.1 ml / Plate. Plates were incubated at 37ºC for 48-72h and after this period colonies were counted. The test substance resulted to be non mutagenic to the tester strains with and without metabolic activation.