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Study Information
Study Attribute Value
CEBS Accession Number: 002-02418-0002-0000-9
Chemical Name: Methdilazine hydrochloride
CASRN: 1229-35-2
NTP Study Type: Genetic Toxicology - Mammalian Cell Cytogenetics
NTP Study ID: 645558_CA
Study Result: Negative

Study Result: Negative
Activation Trial Trial Call
No Activation  1  Negative 
Induced Rat Liver S9  1_S9  Negative 
No Activation  2  Negative 
Induced Rat Liver S9  2_S9  Test Failure 

Trial #:1   Activation: No Activation    Date: 07/27/1982    Harvest Time: 11 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: Medium 
0         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0
Negative (Not Specified) 
0         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0
Test Chemical: Methdilazine hydrochloride 
 0.05      
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
 0.16      
 100 1 0.010 1.0 0 0.000 0.0 1 0.010 1.0 0 0.000 0.0 
 0.5       
 100 1 0.010 1.0 0 0.000 0.0 1 0.010 1.0 0 0.000 0.0 
1.6       
 100 2 0.020 2.0 2 0.020 2.0 0 0.000 0.0 0 0.000 0.0 
5         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
16         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
50         
 0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0
Positive Control: Mitomycin-C 
 0.25      
 100 29 0.290 23.0 10 0.100 10.0 12 0.120 11.0 7 0.070 7.0
Trend: 0.254 0.711 -0.353  
Probability: 0.400 0.238 0.638  


Trial #:1_S9   Activation: Induced Rat Liver S9    Date: 07/27/1982    Harvest Time: 11.5 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 0 0.000 0.0 0 0.000 0.0 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: Methdilazine hydrochloride 
 0.05      
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
 0.16      
 100 1 0.010 1.0 1 0.010 1.0 0 0.000 0.0 0 0.000 0.0 
 0.5       
 100 2 0.020 2.0 0 0.000 0.0 2 0.020 2.0 0 0.000 0.0 
1.6       
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
5         
 100 3 0.030 2.0 1 0.010 1.0 2 0.020 2.0 0 0.000 0.0 
16         
 100 1 0.010 1.0 1 0.010 1.0 0 0.000 0.0 0 0.000 0.0 
50         
 0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0
Positive Control: Cyclophosphamide 
50         
 100 116 1.160 67.0 71 0.710 43.0 23 0.230 19.0 22 0.220 22.0
Trend: 1.227 1.158 0.997  
Probability: 0.110 0.123 0.159  


Trial #:2   Activation: No Activation    Date: 07/27/1982    Harvest Time: 12 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: Medium 
0         
 100 1 0.010 1.0 0 0.000 0.0 1 0.010 1.0 0 0.000 0.0
Negative (Not Specified) 
0         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0
Test Chemical: Methdilazine hydrochloride 
1         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
2.5       
 100 1 0.010 1.0 1 0.010 1.0 0 0.000 0.0 0 0.000 0.0 
5         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
7.5       
 100 1 0.010 1.0 0 0.000 0.0 1 0.010 1.0 0 0.000 0.0 
10         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
20         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0
Positive Control: Mitomycin-C 
 0.25      
 100 34 0.340 28.0 17 0.170 17.0 7 0.070 7.0 10 0.100 9.0
Trend: -0.791 -0.339 -0.728  
Probability: 0.785 0.633 0.767  


Trial #:2_S9   Activation: Induced Rat Liver S9    Date: 07/27/1982    Harvest Time: 12 hour(s)   Trial Call: Test Failure   
  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: Medium 
0         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0
Negative (Not Specified) 
0         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0
Test Chemical: Methdilazine hydrochloride 
5         
 0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
10         
 0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
20         
 0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
30         
 0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
40         
 0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
50         
 0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0
Positive Control: Cyclophosphamide 
50         
 100 131 1.310 54.0 45 0.450 30.0 46 0.460 29.0 40 0.400 27.0
Trend: 0.000 0.000 0.000  
Probability: 0.000 0.000 0.000