U.S. flag

An official website of the United States government

Dot gov

The .gov means it's official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you're on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Study Information
Study Attribute Value
CEBS Accession Number: 002-02971-0003-0000-4
Chemical Name: Trimethylthiourea
CASRN: 2489-77-2
NTP Study Type: Genetic Toxicology - Mammalian Cell Cytogenetics
NTP Study ID: 724688_SCE
Study Result: Negative

Study Result: Negative
Activation Trial Trial Call
No Activation  1  Negative 
Induced Rat Liver S9  1_S9  Negative 

Trial #: 1    Activation: No Activation    Date: 07/24/1990    Trial Call: Negative   
  Dose
µg/mL		 Number
Cells
Examined		 Number
Chromosomes
Examined		 Total
Number
SCEs		 SCE /
Chromosome		 SCE /
Cell		 Hours in
BRDU		 % Increase
Over Solvent
Control
Vehicle Control Dimethyl Sulfoxide 
0         
 50 1051 407 0.387 8.14 31.0 7.752
Dimethyl Sulfoxide 
0         
 50 1049 377 0.359 7.54 26.0 0.000
Test Chemical Trimethylthiourea 
125         
 50 1048 360 0.344 7.20 26.0 -4.418 
417         
 50 1052 386 0.367 7.72 26.0 2.095 
1250         
 50 1050 408 0.389 8.16 31.0 8.120
Positive Control Mitomycin-C 
 0.001     
 50 1051 515 0.490 10.30 26.0 36.345
Mitomycin-C 
 0.004     
 10 211 254 1.204 25.40 26.0 234.954
Trend: 1.327        
Probability: 0.092        

Trial #: 1_S9    Activation: Induced Rat Liver S9    Date: 07/24/1990    Trial Call: Negative   
  Dose
µg/mL		 Number
Cells
Examined		 Number
Chromosomes
Examined		 Total
Number
SCEs		 SCE /
Chromosome		 SCE /
Cell		 Hours in
BRDU		 % Increase
Over Solvent
Control
Vehicle Control Dimethyl Sulfoxide 
0         
 50 1049 416 0.397 8.32 26.0 0.000
Trimethylthiourea 
0         
 50 1050 401 0.382 8.02 26.0 -3.698
Test Chemical Trimethylthiourea 
125         
 50 1047 401 0.383 8.02 26.0 -3.422 
417         
 50 1048 397 0.379 7.94 26.0 -4.476 
1250         
 50 1046 412 0.394 8.24 26.0 -0.677
Positive Control Cyclophosphamide 
 0.125     
 50 1049 566 0.540 11.32 26.0 36.058
Cyclophosphamide 
 0.5       
 10 209 224 1.072 22.40 26.0 170.261
Trend: -0.152        
Probability: 0.561