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Study Information
Study Attribute Value
CEBS Accession Number: 002-02419-0003-0000-1
Chemical Name: Methoxychlor
CASRN: 72-43-5
NTP Study Type: Genetic Toxicology - Mammalian Cell Cytogenetics
NTP Study ID: 639870_SCE
Study Result: Not a Valid Test

Study Result: Not a Valid Test
Activation Trial Trial Call
No Activation  1  Test Failure 
Induced Rat Liver S9  1_S9  Test Failure 

Trial #: 1    Activation: No Activation    Date: 09/07/1983    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 Dimethyl Sulfoxide 
0         
 50 1024 475 0.464 9.50 25.6 0.000
Test Chemical Methoxychlor 
 0.5       
 50 1019 515 0.505 10.30 25.6 8.953 
1.7       
 50 1033 708 0.685 14.16 34.3 47.754 
5         
 50 1033 761 0.737 15.22 34.3 58.815 
16.7       
 0 0 0 0.000 0.00 0.0 N/A
Positive Control Mitomycin-C 
 0.001     
 50 1040 636 0.612 12.72 25.6 31.835
Mitomycin-C 
 0.1       
 5 105 230 2.190 46.00 25.6 372.221
Trend: 9.289        
Probability: 0.000        

Trial #: 1_S9    Activation: Induced Rat Liver S9    Date: 09/07/1983    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 Dimethyl Sulfoxide 
0         
 50 1028 475 0.462 9.50 25.6 0.000
Test Chemical Methoxychlor 
50         
 50 1029 560 0.544 11.20 25.6 17.780 
166.7       
 50 1020 743 0.728 14.86 34.3 57.648 
500         
 50 1040 856 0.823 17.12 34.3 78.131 
1700         
 0 0 0 0.000 0.00 0.0 N/A
Positive Control Cyclophosphamide 
 0.3       
 50 1029 600 0.583 12.00 25.6 26.193
Cyclophosphamide 
2         
 5 103 155 1.505 31.00 25.6 225.682
Trend: 11.397        
Probability: 0.000