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: 002-01015-0001-0000-0
Chemical Name: 1,1,1-Trichloroethane
CASRN: 71-55-6
NTP Study Type: Genetic Toxicology - Mammalian Cell Cytogenetics
NTP Study ID: 631930_SCE
Study Result: Equivocal

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

Trial #: 1    Activation: No Activation    Date: 12/08/1982    Trial Call: Negative   
  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 1047 417 0.398 8.34 26.0 0.000
Test Chemical 1,1,1-Trichloroethane 
500         
 50 1044 386 0.370 7.72 26.0 -7.168 
750         
 50 1045 458 0.438 9.16 26.0 10.042 
1000         
 50 1043 459 0.440 9.18 26.0 10.494
Positive Control Mitomycin-C 
 0.005     
 25 525 710 1.352 28.40 26.0 239.555
Trend: 2.243        
Probability: 0.012        

Trial #: 2    Activation: No Activation    Date: 10/20/1983    Trial Call: Questionable   
  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 1047 430 0.411 8.60 26.0 0.000
Test Chemical 1,1,1-Trichloroethane 
16         
 50 1051 510 0.485 10.20 26.0 18.153 
50         
 50 1051 425 0.404 8.50 26.0 -1.539 
160         
 50 1048 443 0.423 8.86 26.0 2.925 
500         
 50 1050 528 0.503 10.56 26.0 22.440
Positive Control Mitomycin-C 
 0.005     
 50 1054 900 0.854 18.00 26.0 107.912
Trend: 1.869        
Probability: 0.031        

Trial #: 1_S9    Activation: Induced Rat Liver S9    Date: 10/20/1982    Trial Call: Questionable   
  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 1045 482 0.461 9.64 26.0 0.000
Test Chemical 1,1,1-Trichloroethane 
16         
 50 1043 448 0.430 8.96 26.0 -6.876 
50         
 50 1041 494 0.475 9.88 26.0 2.883 
160         
 50 1045 537 0.514 10.74 26.0 11.411 
500         
 50 1045 537 0.514 10.74 26.0 11.411
Positive Control Cyclophosphamide 
1         
 25 523 487 0.931 19.48 26.0 101.882
Trend: 2.803        
Probability: 0.003