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Study Information
Study Attribute Value
CEBS Accession Number: 002-02237-0011-0000-8
Chemical Name: Heptachlor
CASRN: 76-44-8
NTP Study Type: Genetic Toxicology - Mammalian Cell Mutagenicity
NTP Study ID: 466460
Study Result: Positive


Table Instructions and Notes:
Studies are indicated to be "Nontoxic" when the observed reductions in relative total growth did not indicate that the maximum tolerated dose was achieved.

Nonactivation Trial: 1 Experiment Call: Positive
  Conc.
ug/mL 		Cloning
Efficiency 		Relative Total
Growth 		Mutant Colonies Mutant Frequency Avg Mutant Frequency
Vehicle Control Dimethyl Sulfoxide 
 0         
 68 92 98 48 44
    81 97 111 46
    92 113 115 42
    64 98 79 41
Test Chemical Heptachlor 
2.5       
 78 101 111 47 45
    86 97 109 42
  
5         
 79 86 102 43 50
    74 82 126 57
  
10         
 78 95 145 62 51
    83 66 100 40
  
20         
 65 81 140 72 59
    80 72 109 46
  
40         
 57 31 167 99 95*
    67 32 186 92
Positive Control Methyl Methane Sulfonate 
15         
 49 33 197 135 160*
    32 22 179 185

Nonactivation Trial: 2 Experiment Call: Negative
  Conc.
ug/mL 		Cloning
Efficiency 		Relative Total
Growth 		Mutant Colonies Mutant Frequency Avg Mutant Frequency
Vehicle Control Dimethyl Sulfoxide 
 0         
 64 91 95 49 49
    58 94 68 39
    63 102 96 51
    65 113 113 58
Test Chemical Heptachlor 
5         
 63 85 51 27 34
    56 75 70 42
  
10         
 66 94 90 45 43
    61 81 73 40
  
20         
 75 70 76 34 45
    61 66 102 56
  
30         
 53 21 73 46 49
    42 20 67 53
  
40         
 19 4 28 48 61
    12 3 27 73
  
50         
   
Positive Control Methyl Methane Sulfonate 
15         
 29 27 111 130 150*
    38 28 194 170

Nonactivation Trial: 3 Experiment Call: Positive
  Conc.
ug/mL 		Cloning
Efficiency 		Relative Total
Growth 		Mutant Colonies Mutant Frequency Avg Mutant Frequency
Vehicle Control Dimethyl Sulfoxide 
 0         
 76 112 62 27 21
    71 92 52 24
    79 91 33 14
    81 105 40 17
Test Chemical Heptachlor 
5         
 70 91 35 17 16
    68 84 31 15
  
10         
 60 82 45 25 21
    87 81 45 17
  
15         
 67 75 40 20 20
    64 79 38 20
  
25         
 67 50 115 57 53*
    70 55 105 50
  
35         
   
Positive Control Methyl Methane Sulfonate 
15         
 39 34 95 82 78*
    46 36 103 74
Methyl Methane Sulfonate 
250         
 60 88 301 168 142*
    72 85 252 117

Footnotes:
Asterisks(*) indicate significant responses.
r = rejected value due to quality control criteria
# = reduced sample size because of the loss of one culture dish due to contamination