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Template for Mammalian Erythrocyte Micronucleus Test

Introduction to the Template for Mammalian Erythrocyte Micronucleus Test

March 2004

Return to Toxicology Template Introduction

Table of Contents

  1. Identification Of Test
  2. Good Laboratory Practice
  3. Materials And Methods
    1. Test Substance
      1. Chemical Name:
      2. CAS Registry Name:
      3. CAS Registry Number:
      4. Structure:
      5. Purity:
      6. Impurities:
      7. Physical Description:
      8. Stability:
    2. Test Substance As Administered
      1. Batch/Lot Number:
      2. Vehicle Used:
      3. Tested Adequately For Concentration?
      4. Tested For Stability?
      5. Problems With Storage?
    3. Experimental Methodology
      1. Experimental Animals:
      2. Control Agents:
      3. Test Substance Concentrations:
      4. Treatment And Sampling Time(S):
      5. Cells Examined:
      6. Slide Preparation:
      7. Evaluation Criteria:
      8. Statistical Methods:
  4. Results
    1. Preliminary Toxicity Test:
    2. Micronucleus Test:
      1. Summary Of Micronucleus Test
  5. Overall Assessment And Summary
    1. Assessment Of Test:
    2. Executive Summary:
  6. References


Genetic Toxicity Studies: Mammalian Erythrocyte Micronucleus Test1  

Date Of Submission:

Title Of Petition Or Notification:                

Name And Address Of Petitioner Or Notifier:    

I.  Identification Of Test

A.    Test File Location (Volume And Page Number(s)):
B.    Test Title/Report Number:
C.    Test Author Or Director:
D.    Name And Address Of Testing Laboratory:
E.    Date Of Test Report:
F.    Dates Test Conducted:
G.   Study Objective:
H.   Comments:

II.  Good Laboratory Practice2  

A.    Is A Good Laboratory Practice (GLP) Compliance Statement Included?       
B.    Is A Quality Assurance (Qa) Statement Included?
C.    Availability And Location Of Original Data/Specimens/Test Substance:  

III. Materials And Methods

A.   Test Substance

  1.     Chemical Name:       
  2.     CAS Registry Name:            
  3.     CAS Registry Number:       
  4.      Structure: 3        
  5.      Purity:
  6.      Impurities:      
  7.      Physical Description:      
  8.     Stability:         


B.   Test Substance As Administered4  

  1.      Batch/Lot Number:            
  2.      Vehicle Used:            
  3.      Tested For Concentration?        
  4.      Tested For Stability?        
  5.       Problems With Storage?  

C.   Experimental Methodology5

1.      Experimental Animals:     

Weight (Start of Treatment)6Males: Females: 
Number of Animals/DoseMales: Females: 
Properly Maintained?7 




2.        Control Agents: 8         

Negative (If Not Vehicle):Final Volume:Route:
Vehicle:Final Volume:Route:
Positive:Final Dose(s):Route:




3.      Test Substance Concentrations:          

(mg/kg body weight)/Final volume/Route:

Preliminary Toxicity Test: 
Micronucleus Test: 



4.      Treatment And Sampling Time(s):      

Test Material

Preliminary Toxicity Test

Micronucleus Test

Dosing Schedule

Sampling Time(s) After Last Dose

Dosing Schedule9  

Sampling Time(s) After Last Dose

Test Substance





Solvent Control





Positive Control











5.         Cells Examined: 10        


Bone marrow erythrocytes


Peripheral blood erythrocytes


Other: (specify)

No. of polychromatic erythrocytes (PCE) scored per animal:
No. of normochromatic erythrocytes (NCE) scored per animal:




6.         Slide Preparation: 11    
7.        Evaluation Criteria: 12            
8.        Statistical Methods: 13            

IV. Results

A.   Preliminary Toxicity Test: 14  



B.   Micronucleus Test: 15  

1.      Table 1. Summary Of Micronucleus Test

Test Material Concentration (mg/kg)

Sampling Time


# Of Animals

Pces  ±  Sd

Nces  ±  Sd

Pce/Nce Ratio Or % Pce





















































































Solvent Control

























Positive Control













MN:      Micronucleated
NCE:    Normochromatic erythrocyte, a mature erythrocyte that lacks ribosomes.
PCE:     Polychromatic erythrocyte, an immature erythrocyte in an intermediate stage of development, which still contains ribosomes.


V. Overall Assessment And Summary

A.   Assessment Of Test: 16  



B.     Executive Summary: 17  


VI. References


End Notes

This section includes some comments that are only relevant when using the Word template.

 1 FDA recommendations for conducting Mammalian Erythrocyte Micronucleus Test in vivo are contained in http://www.cfsan.fda.gov/~redbook/redivc1d.html

 2 Indicate Yes or No for the Questions A and B.  However, you may want to elaborate on the type of GLP compliance (USFDA, OECD, etc.) or make other notations.

 3 If the molecular structure is not provided with the test, it may be available from a source such as Chemfinder (http://www.chemfinder.com) or ChemIDplus (http://chem.sis.nlm.nih.gov/chemidplus/).  The CAS number is the preferred search term if you have it; otherwise try the common name or any synonyms. If the correct structure is found on Chemfinder or ChemIDplus, the image can be downloaded and inserted into your report.  If the structure is not available, enter 'Not available'.

 4 Indicate how the test substance was administered and whether any vehicle was used to dissolve/suspend the test substance (e.g., dissolved in dimethylsulfoxide).  Also note how testings for concentration and stability were done.  Was the test substance in vehicle, etc., stored before being used in the test? Note anything that was not normal or routine.

 5 Provide adequate details so the information can be used to help prepare a report. Use the comments to indicate additional information about the experimental methodology.  To change the table, place cursor in the row or column that you wish to modify, then from the 'Table' menu, use 'Select Row' or 'Select Column' to highlight the row or column that you wish to change, and use the 'delete' or 'insert' functions to make your changes.

 6 Animal weights may be entered as ranges or means (in grams) or both, depending on what information is provided in the study.  Individual animal weights should not be entered. 

 7 Provide adequate details on how animals were maintained. Further explanation can be given in the comment section.  Animal housing and feeding conditions are discussed in the FDA Redbook for this test.

 8 A negative control (completely untreated) is not required and typically not provided in this test when an acceptable vehicle control is used. Just enter "none" in this case. 

 9 Enter dosing schedule, for example "Once", "Twice - 24 hours apart".

 10 Put an x in the box next to the appropriate cell source, almost always bone marrow but occasionally peripheral blood. If some other source was used, specify.

 11 Briefly describe cell isolation and slide preparation procedures and state if slides were coded prior to analysis.

 12 Describe the definition/description of micronuclei used, the data obtained, the laboratory's criteria for an acceptable test and criteria for a positive and negative response.

 13 Briefly state which data were analyzed and what statistical method(s) were used.

 14 If a preliminary toxicity test was conducted, report the results including dose range, number and sex of animals used, mortality, clinical signs and the justification for dose selection for the micronucleus test.

 15 Report the results of the micronucleus test including toxicity, the frequency of micronucleated PCEs and NCEs (if provided) for the test material treated and solvent and positive control treated animals, the PCE/NCE ratios, sex differences in response and statistical evaluation if conducted.  The experimental unit is the animal.  This table can be modified and/or duplicated as required.

 16 Briefly summarize the test, including potential deficiencies that affected the conclusions of the test 

 17 The executive summary should be a brief, concise, stand-alone summary describing the test system, the test protocol and the results.

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