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Study Information
Study Attribute Value
CEBS Accession Number: 002-03114-0001-0000-2
Chemical Name: o-Chlorobenzalmalononitrile (CS)
CASRN: 2698-41-1
NTP Study Type: Genetic Toxicology - Mammalian Cell Cytogenetics
NTP Study ID: 171099_SCE
Study Result: Positive

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

Trial #: 1    Activation: No Activation    Date: 02/08/1983    Trial Call: Test Failure   
  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 Acetone 
0         
 50 1047 557 0.532 11.14 25.5 0.000
Test Chemical o-Chlorobenzalmalononitrile (CS) 
3.3       
 50 1045 709 0.678 14.18 33.0 27.533 
10         
 0 0 0 0.000 0.00 33.0 N/A
Positive Control Mitomycin-C 
 0.01      
 5 101 173 1.713 34.60 25.5 221.971
Trend: 4.306        
Probability: 0.000        

Trial #: 2    Activation: No Activation    Date: 03/07/1983    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 Acetone 
0         
 50 1042 494 0.474 9.88 25.7 0.000
Test Chemical o-Chlorobenzalmalononitrile (CS) 
6         
 50 1046 640 0.612 12.80 32.0 29.059 
7         
 50 1048 730 0.697 14.60 32.0 46.927 
8         
 50 1036 757 0.731 15.14 32.0 54.126 
9         
 0 0 0 0.000 0.00 32.0 N/A
Positive Control Mitomycin-C 
 0.001     
 50 1041 604 0.580 12.08 25.7 22.385
Mitomycin-C 
 0.01      
 5 105 165 1.571 33.00 25.7 231.463
Trend: 7.780        
Probability: 0.000        

Trial #: 1_S9    Activation: Induced Rat Liver S9    Date: 02/08/1983    Trial Call: Weakly 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 Acetone 
0         
 50 1044 464 0.444 9.28 25.5 0.000
Test Chemical o-Chlorobenzalmalononitrile (CS) 
1         
 50 1035 494 0.477 9.88 25.5 7.391 
3.3       
 50 1040 531 0.511 10.62 25.5 14.880 
10         
 50 1044 799 0.765 15.98 33.0 72.198 
33         
 0 0 0 0.000 0.00 0.0 N/A
Positive Control Cyclophosphamide 
2         
 5 105 161 1.533 32.20 25.5 245.000
Trend: 9.629        
Probability: 0.000        

Trial #: 2_S9    Activation: Induced Rat Liver S9    Date: 03/07/1983    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 Acetone 
0         
 50 1045 449 0.430 8.98 25.7 0.000
Test Chemical o-Chlorobenzalmalononitrile (CS) 
10         
 50 1042 605 0.581 12.10 32.0 35.132 
12.5       
 50 1040 729 0.701 14.58 32.0 63.141 
15         
 50 1043 730 0.700 14.60 32.0 62.895 
17.5       
 0 0 0 0.000 0.00 32.0 N/A
Positive Control Cyclophosphamide 
 0.3       
 50 1035 634 0.613 12.68 25.7 42.567
Cyclophosphamide 
2         
 5 104 139 1.337 27.80 25.7 211.065
Trend: 8.706        
Probability: 0.000