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Study Information
Study Attribute Value
CEBS Accession Number: 002-02889-0001-0000-0
Chemical Name: Tetrakis(hydroxymethyl)phosphonium sulfate
CASRN: 55566-30-8
NTP Study Type: Genetic Toxicology - Mammalian Cell Cytogenetics
NTP Study ID: 322690_SCE
Study Result: Positive

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

Trial #: 1    Activation: No Activation    Date: 10/30/1986    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 1023 467 0.457 9.34 25.5 0.000
Test Chemical Tetrakis(hydroxymethyl)phosphonium sulfate 
 0.2       
 5 105 134 1.276 26.80 31.8 179.559 
 0.5       
 50 1030 576 0.559 11.52 31.8 22.502 
1.7       
 0 0 0 0.000 0.00 0.0 N/A
Positive Control Mitomycin-C 
 0.001     
 50 1035 624 0.603 12.48 25.5 32.070
Mitomycin-C 
 0.01      
 5 105 260 2.476 52.00 25.5 442.429
Trend: 3.320        
Probability: 0.000        

Trial #: 2    Activation: No Activation    Date: 12/10/1986    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 Dimethyl Sulfoxide 
0         
 25 524 219 0.418 8.76 25.7 0.000
Test Chemical Tetrakis(hydroxymethyl)phosphonium sulfate 
 0.2       
 25 517 222 0.429 8.88 25.7 2.742 
 0.5       
 25 524 255 0.487 10.20 25.7 16.438 
2         
 25 522 407 0.780 16.28 31.3 86.557 
5.1       
 0 0 0 0.000 0.00 31.3 N/A
Positive Control Mitomycin-C 
 0.001     
 25 524 266 0.508 10.64 25.7 21.461
Mitomycin-C 
 0.01      
 5 105 229 2.181 45.80 25.7 421.835
Trend: 8.346        
Probability: 0.000        

Trial #: 1_S9    Activation: Induced Rat Liver S9    Date: 10/30/1986    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 1034 414 0.400 8.28 25.5 0.000
Test Chemical Tetrakis(hydroxymethyl)phosphonium sulfate 
 0.5       
 50 1036 438 0.423 8.76 25.5 5.593 
1.7       
 10 210 288 1.371 28.80 31.8 242.526 
5         
 25 519 552 1.064 22.08 25.5 165.639 
16.8       
 0 0 0 0.000 0.00 0.0 N/A
Positive Control Cyclophosphamide 
 0.4       
 50 1028 533 0.518 10.66 25.5 29.495
Cyclophosphamide 
2         
 5 103 90 0.874 18.00 25.5 118.236
Trend: 19.114        
Probability: 0.000        

Trial #: 2_S9    Activation: Induced Rat Liver S9    Date: 12/10/1986    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         
 25 522 190 0.364 7.60 25.7 0.000
Test Chemical Tetrakis(hydroxymethyl)phosphonium sulfate 
 0.5       
 25 523 234 0.447 9.36 25.7 22.922 
1.7       
 25 521 278 0.534 11.12 25.7 46.597 
5.1       
 25 520 440 0.846 17.60 31.3 132.470 
10.1       
 0 0 0 0.000 0.00 31.3 N/A
Positive Control Cyclophosphamide 
 0.4       
 25 520 260 0.500 10.40 25.7 37.368
Cyclophosphamide 
2         
 5 104 169 1.625 33.80 25.7 346.447
Trend: 10.583        
Probability: 0.000