COVID-19 is an emerging, rapidly evolving situation.

Get the latest public health information from CDC and research information from NIH.

U.S. flag

An official website of the United States government

Dot gov

The .gov means it's official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you're on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Share This:
Study Information
Study Attribute Value
CEBS Accession Number: 002-02088-0002-0000-2
Chemical Name: Diphenhydramine hydrochloride
CASRN: 147-24-0
NTP Study Type: Genetic Toxicology - Mammalian Cell Cytogenetics
NTP Study ID: 195192_CA
Study Result: Positive

Study Result: Positive
Activation Trial Trial Call
No Activation  1  Negative 
Induced Rat Liver S9  1_S9  Negative 
No Activation  2  Positive 
No Activation  3  Positive 
No Activation  4  Negative 

Trial #:1   Activation: No Activation    Date: 09/05/1984    Harvest Time: 18.5 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 2 0.020 1.0 0 0.000 0.0 2 0.020 1.0 0 0.000 0.0
Test Chemical: Diphenhydramine hydrochloride 
100         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
161         
 100 3 0.030 3.0 0 0.000 0.0 3 0.030 3.0 0 0.000 0.0 
181         
 27 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
201         
 67 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0
Positive Control: Mitomycin-C 
5         
 100 580 5.800 92.0 73 0.730 37.0 60 0.600 33.0 447 4.470 51.0
Trend: 0.435 0.000 0.435  
Probability: 0.332 0.000 0.332  


Trial #:1_S9   Activation: Induced Rat Liver S9    Date: 07/26/1984    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
Test Chemical: Diphenhydramine hydrochloride 
30.3       
 100 2 0.020 2.0 0 0.000 0.0 2 0.020 2.0 0 0.000 0.0 
101         
 100 3 0.030 3.0 0 0.000 0.0 3 0.030 3.0 0 0.000 0.0 
300         
 100 3 0.030 2.0 2 0.020 2.0 1 0.010 1.0 0 0.000 0.0
Positive Control: Cyclophosphamide 
50         
 100 60 0.600 32.0 23 0.230 20.0 16 0.160 16.0 21 0.210 3.0
Trend: 1.209 1.876 0.760  
Probability: 0.113 0.030 0.224  


Trial #:2   Activation: No Activation    Date: 10/10/1984    Harvest Time: 22 hour(s)   Trial Call: Positive   
  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 2 0.020 2.0 1 0.010 1.0 1 0.010 1.0 0 0.000 0.0
Test Chemical: Diphenhydramine hydrochloride 
100         
 100 22 0.220 13.0 8 0.080 7.0 14 0.140 10.0 0 0.000 0.0 
125         
 100 14 0.140 12.0 1 0.010 1.0 13 0.130 11.0 0 0.000 0.0 
150         
 41 18 0.439 44.0 2 0.049 5.0 16 0.390 39.0 0 0.000 0.0
Positive Control: Mitomycin-C 
5         
 15 128 8.533 93.0 7 0.467 13.0 1 0.067 7.0 120 8.000 12.0
Trend: 5.466 0.362 5.497  
Probability: 0.000 0.359 0.000  


Trial #:3   Activation: No Activation    Date: 08/23/1984    Harvest Time: 18.5 hour(s)   Trial Call: Positive   
  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
Test Chemical: Diphenhydramine hydrochloride 
10         
 100 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 0 0.000 0.0 
50         
 100 1 0.010 1.0 0 0.000 0.0 1 0.010 1.0 0 0.000 0.0 
100         
 100 1 0.010 1.0 1 0.010 1.0 0 0.000 0.0 0 0.000 0.0 
150         
 100 9 0.090 8.0 1 0.010 1.0 8 0.080 7.0 0 0.000 0.0 
200         
 100 29 0.290 17.0 10 0.100 8.0 19 0.190 12.0 0 0.000 0.0
Positive Control: Mitomycin-C 
5         
 100 540 5.400 81.0 52 0.520 28.0 34 0.340 17.0 454 4.540 49.0
Trend: 5.171 3.248 4.399  
Probability: 0.000 0.001 0.000  


Trial #:4   Activation: No Activation    Date: 07/26/1984    Harvest Time: 10.5 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 16 0.160 4.0 4 0.040 3.0 12 0.120 2.0 0 0.000 0.0
Test Chemical: Diphenhydramine hydrochloride 
15.2       
 100 1 0.010 1.0 0 0.000 0.0 1 0.010 1.0 0 0.000 0.0 
50.5       
 100 2 0.020 2.0 0 0.000 0.0 2 0.020 2.0 0 0.000 0.0 
150         
 100 1 0.010 1.0 1 0.010 1.0 0 0.000 0.0 0 0.000 0.0 
300         
 39 1 0.026 3.0 0 0.000 0.0 1 0.026 3.0 0 0.000 0.0
Positive Control: Mitomycin-C 
5         
 100 52 0.520 38.0 28 0.280 24.0 24 0.240 18.0 0 0.000 0.0
Trend: -0.846 -1.490 -0.370  
Probability: 0.801 0.932 0.644