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Study Information
Study Attribute Value
CEBS Accession Number: 002-02675-0002-0000-4
Chemical Name: Phenoxybenzamine hydrochloride
CASRN: 63-92-3
NTP Study Type: Genetic Toxicology - Mammalian Cell Cytogenetics
NTP Study ID: 926929_CA
Study Result: Positive

Study Result: Positive
Activation Trial Trial Call
No Activation  1  Negative 
Induced Rat Liver S9  1_S9  Weakly Positive* 
Induced Rat Liver S9  2_S9  Weakly Positive* 

Trial #:1   Activation: No Activation    Date: 09/28/1987    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: Dimethyl Sulfoxide 
0         
 200 2 0.010 1.0 1 0.005 0.5 1 0.005 0.5 0 0.000 0.0
Test Chemical: Phenoxybenzamine hydrochloride 
10         
 200 9 0.045 3.5 2 0.010 1.0 7 0.035 2.5 0 0.000 0.0 
16         
 200 6 0.030 2.5 3 0.015 1.5 3 0.015 1.5 0 0.000 0.0 
30         
 200 5 0.025 2.5 2 0.010 1.0 3 0.015 1.5 0 0.000 0.0
Positive Control: Mitomycin-C 
 0.0625    
 200 35 0.175 16.0 19 0.095 9.5 16 0.080 7.5 0 0.000 0.0
Mitomycin-C 
 0.25      
 50 19 0.380 32.0 13 0.260 22.0 6 0.120 12.0 0 0.000 0.0
Trend: 0.729 0.598 0.527  
Probability: 0.233 0.275 0.299  


Trial #:1_S9   Activation: Induced Rat Liver S9    Date: 11/03/1987    Harvest Time: 13 hour(s)   Trial Call: Weakly 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: Dimethyl Sulfoxide 
0         
 200 2 0.010 1.0 0 0.000 0.0 2 0.010 1.0 0 0.000 0.0
Test Chemical: Phenoxybenzamine hydrochloride 
10         
 200 3 0.015 1.5 2 0.010 1.0 1 0.005 0.5 0 0.000 0.0 
16         
 200 3 0.015 1.5 0 0.000 0.0 3 0.015 1.5 0 0.000 0.0 
30         
 200 24 0.120 12.0 4 0.020 2.0 20 0.100 10.0 0 0.000 0.0
Positive Control: Cyclophosphamide 
2.5       
 200 37 0.185 17.0 9 0.045 4.5 28 0.140 13.5 0 0.000 0.0
Cyclophosphamide 
7.5       
 50 19 0.380 34.0 4 0.080 8.0 15 0.300 28.0 0 0.000 0.0
Trend: 5.513 1.937 5.150  
Probability: 0.000 0.026 0.000  


Trial #:2_S9   Activation: Induced Rat Liver S9    Date: 09/28/1987    Harvest Time: 13 hour(s)   Trial Call: Weakly 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: Dimethyl Sulfoxide 
0         
 200 1 0.005 0.5 0 0.000 0.0 1 0.005 0.5 0 0.000 0.0
Test Chemical: Phenoxybenzamine hydrochloride 
10         
 200 5 0.025 2.5 1 0.005 0.5 4 0.020 2.0 0 0.000 0.0 
16         
 200 5 0.025 2.5 2 0.010 1.0 3 0.015 1.5 0 0.000 0.0 
30         
 200 25 0.125 11.5 6 0.030 3.0 17 0.085 8.0 2 0.010 2.0
Positive Control: Cyclophosphamide 
2.5       
 200 42 0.210 18.0 9 0.045 4.0 33 0.165 15.0 0 0.000 0.0
Cyclophosphamide 
7.5       
 50 20 0.400 28.0 6 0.120 12.0 14 0.280 24.0 0 0.000 0.0
Trend: 5.321 2.897 4.213  
Probability: 0.000 0.002 0.000