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Study Information
Study Attribute Value
CEBS Accession Number: 002-02122-0002-0000-1
Chemical Name: Erythromycin stearate
CASRN: 643-22-1
NTP Study Type: Genetic Toxicology - Mammalian Cell Cytogenetics
NTP Study ID: 756378_CA
Study Result: Negative

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

Trial #:1   Activation: No Activation    Date: 08/02/1984    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         
 100 2 0.020 2.0 0 0.000 0.0 2 0.020 2.0 0 0.000 0.0
Test Chemical: Erythromycin stearate 
160         
 100 4 0.040 3.0 0 0.000 0.0 3 0.030 2.0 1 0.010 1.0 
300         
 100 3 0.030 3.0 0 0.000 0.0 2 0.020 2.0 1 0.010 1.0 
400         
 100 3 0.030 3.0 0 0.000 0.0 2 0.020 2.0 1 0.010 1.0 
500         
 100 1 0.010 1.0 0 0.000 0.0 0 0.000 0.0 1 0.010 1.0
Positive Control: Mitomycin-C 
 0.15      
 100 7 0.070 6.0 5 0.050 4.0 2 0.020 2.0 0 0.000 0.0
Mitomycin-C 
 0.25      
 100 26 0.260 20.0 17 0.170 14.0 9 0.090 9.0 0 0.000 0.0
Trend: -0.265 0.000 -0.851  
Probability: 0.605 0.000 0.803  


Trial #:1_S9   Activation: Induced Rat Liver S9    Date: 06/28/1984    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: Negative (Not Specified) 
0         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0
Dimethyl Sulfoxide 
0         
 100 1 0.010 1.0 0 0.000 0.0 0 0.000 0.0 1 0.010 1.0
Test Chemical: Erythromycin stearate 
50         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
160         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
500         
 100 1 0.010 1.0 0 0.000 0.0 1 0.010 1.0 0 0.000 0.0
Positive Control: Cyclophosphamide 
15         
 100 10 0.100 9.0 5 0.050 5.0 5 0.050 5.0 0 0.000 0.0
Cyclophosphamide 
50         
 50 27 0.540 38.0 12 0.240 22.0 14 0.280 26.0 1 0.020 1.0
Trend: -0.003 0.000 1.340  
Probability: 0.501 0.000 0.090  


Trial #:2   Activation: No Activation    Date: 06/29/1984    Harvest Time: 12.5 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: Negative (Not Specified) 
0         
 100 1 0.010 1.0 0 0.000 0.0 1 0.010 1.0 0 0.000 0.0
Dimethyl Sulfoxide 
0         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0
Test Chemical: Erythromycin stearate 
16         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
50         
 100 2 0.020 2.0 1 0.010 1.0 1 0.010 1.0 0 0.000 0.0 
160         
 100 3 0.030 3.0 0 0.000 0.0 3 0.030 3.0 0 0.000 0.0 
500         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0
Positive Control: Mitomycin-C 
 0.25      
 100 36 0.360 28.0 28 0.280 22.0 8 0.080 8.0 0 0.000 0.0
Mitomycin-C 
1         
 50 27 0.540 40.0 18 0.360 34.0 9 0.180 14.0 0 0.000 0.0
Trend: 0.955 -0.005 1.069  
Probability: 0.170 0.502 0.143