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Study Information
Study Attribute Value
CEBS Accession Number: 002-01515-0001-0000-5
Chemical Name: 4-Nitro-o-phenylenediamine
CASRN: 99-56-9
NTP Study Type: Genetic Toxicology - Mammalian Cell Cytogenetics
NTP Study ID: 549927_SCE
Study Result: Positive

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

Trial #: 1    Activation: No Activation    Date: 05/01/1984    Trial Call: Positive   
  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 Negative (Not Specified) 
0         
 50 1046 435 0.416 8.70 26.5 -4.332
Medium 
0         
 50 1049 456 0.435 9.12 26.5 0.000
Test Chemical 4-Nitro-o-phenylenediamine 
1.6       
 50 1045 593 0.567 11.86 26.0 30.542 
5         
 50 1048 670 0.639 13.40 26.0 47.070 
16         
 50 1049 816 0.778 16.32 26.0 78.947 
50         
 50 1047 1213 1.159 24.26 26.0 166.517 
160         
 0 0 0 0.000 0.00 26.0 N/A
Positive Control Mitomycin-C 
 0.001     
 50 1050 1302 1.240 26.04 26.5 185.254
Mitomycin-C 
 0.01      
 10 210 749 3.567 74.90 26.5 720.490
Trend: 20.056        
Probability: 0.000        

Trial #: 2    Activation: No Activation    Date: 05/30/1984    Trial Call: Positive   
  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 Negative (Not Specified) 
0         
 50 1047 485 0.463 9.70 26.0 2.852
Dimethyl Sulfoxide 
0         
 50 1048 472 0.450 9.44 26.0 0.000
Test Chemical 4-Nitro-o-phenylenediamine 
5         
 50 1051 649 0.618 12.98 26.0 37.108 
16         
 50 1050 802 0.764 16.04 26.0 69.592 
50         
 50 1042 933 0.895 18.66 26.0 98.808 
75         
 16 336 352 1.048 22.00 26.0 132.607 
100         
 50 1046 1144 1.094 22.88 31.0 142.836 
100         
 0 0 0 0.000 0.00 26.0 N/A 
200         
 0 0 0 0.000 0.00 31.0 N/A
Positive Control Mitomycin-C 
 0.001     
 50 1051 1348 1.283 26.96 26.0 184.778
Mitomycin-C 
 0.01      
 10 210 612 2.914 61.20 26.0 547.070
Trend: 18.793        
Probability: 0.000        

Trial #: 1_S9    Activation: Induced Rat Liver S9    Date: 05/01/1984    Trial Call: Positive   
  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 Negative (Not Specified) 
0         
 50 1046 440 0.421 8.80 26.0 -0.131
Dimethyl Sulfoxide 
0         
 50 1047 441 0.421 8.82 26.0 0.000
Test Chemical 4-Nitro-o-phenylenediamine 
160         
 50 1049 490 0.467 9.80 26.0 10.899 
500         
 50 1048 559 0.533 11.18 26.0 26.636 
1600         
 50 1044 602 0.577 12.04 26.0 36.900 
5000         
 50 1047 879 0.840 17.58 26.0 99.320
Positive Control Cyclophosphamide 
 0.3       
 50 1048 624 0.595 12.48 26.0 41.362
Cyclophosphamide 
2         
 10 210 340 1.619 34.00 26.0 284.386
Trend: 12.850        
Probability: 0.000        

Trial #: 2_S9    Activation: Induced Rat Liver S9    Date: 05/30/1984    Trial Call: Positive   
  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 512 0.488 10.24 26.0 0.000
Negative (Not Specified) 
0         
 50 1048 471 0.449 9.42 26.0 -7.920
Test Chemical 4-Nitro-o-phenylenediamine 
2000         
 50 1047 643 0.614 12.86 26.0 25.826 
3000         
 50 1050 852 0.811 17.04 26.0 66.248 
4000         
 50 1050 856 0.815 17.12 26.0 67.028 
5000         
 50 1047 847 0.809 16.94 26.0 65.746
Positive Control Cyclophosphamide 
 0.3       
 50 1049 640 0.610 12.80 26.0 25.000
Cyclophosphamide 
2         
 10 210 378 1.800 37.80 26.0 268.789
Trend: 10.688        
Probability: 0.000