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Study Information
Study Attribute Value
CEBS Accession Number: 002-02417-0002-0000-8
Chemical Name: Methapyrilene hydrochloride
CASRN: 135-23-9
NTP Study Type: Genetic Toxicology - Mammalian Cell Cytogenetics
NTP Study ID: 184622_CA
Study Result: Positive

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

Trial #:1   Activation: No Activation    Date: 08/02/1983    Harvest Time: 24.2 hour(s)   Trial Call: Negative   
  Dose
µg/mL		 Total
Cells Examined		 Total Aberrations Complex Aberrations Simple Aberrations Other Abs
No. of
Abs		 Abs
Per
Cell		 % Cells
With
Abs		 No. of
Abs.		 Abs
Per
Cell		 % Cells
With
Abs		 No. of
Abs.		 Abs
Per
Cell		 % Cells
With
Abs		 No. of
Abs.		 Abs
Per
Cell		 % Cells
With
Abs
Vehicle Control: Negative (Not Specified) 
0         
 100 1 0.010 1.0 0 0.000 0.0 1 0.010 1.0 0 0.000 0.0
Medium 
0         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0
Test Chemical: Methapyrilene hydrochloride 
352         
 100 2 0.020 1.0 0 0.000 0.0 2 0.020 1.0 0 0.000 0.0 
376         
 100 2 0.020 2.0 0 0.000 0.0 2 0.020 2.0 0 0.000 0.0 
400         
 100 2 0.020 2.0 0 0.000 0.0 2 0.020 2.0 0 0.000 0.0
Positive Control: Mitomycin-C 
 0.05      
 50 26 0.520 36.0 20 0.400 30.0 6 0.120 10.0 0 0.000 0.0
Trend: 1.414 0.000 1.414  
Probability: 0.079 0.000 0.079  


Trial #:1_S9   Activation: Induced Rat Liver S9    Date: 08/11/1983    Harvest Time: 10.5 hour(s)   Trial Call: Positive   
  Dose
µg/mL		 Total
Cells Examined		 Total Aberrations Complex Aberrations Simple Aberrations Other Abs
No. of
Abs		 Abs
Per
Cell		 % Cells
With
Abs		 No. of
Abs.		 Abs
Per
Cell		 % Cells
With
Abs		 No. of
Abs.		 Abs
Per
Cell		 % Cells
With
Abs		 No. of
Abs.		 Abs
Per
Cell		 % Cells
With
Abs
Vehicle Control: Negative (Not Specified) 
0         
 100 1 0.010 1.0 1 0.010 1.0 0 0.000 0.0 0 0.000 0.0
Medium 
0         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0
Test Chemical: Methapyrilene hydrochloride 
747         
 100 12 0.120 10.0 2 0.020 2.0 10 0.100 8.0 0 0.000 0.0 
798         
 100 23 0.230 16.0 1 0.010 1.0 22 0.220 15.0 0 0.000 0.0 
850         
 100 53 0.530 31.0 6 0.060 5.0 47 0.470 27.0 0 0.000 0.0
Positive Control: Cyclophosphamide 
25         
 50 8 0.160 14.0 5 0.100 10.0 2 0.040 4.0 1 0.020 2.0
Trend: 6.323 2.224 5.944  
Probability: 0.000 0.013 0.000