Information Notice No. 84-85: Molybdenum Breakthrough from Technetium-99m Generators

                                                            SSINS 6835  
                                                            IN 84-85 

                               UNITED STATES 
                           WASHINGTON, D.C. 20555 

                             November 30, 1984 



All NRC medical licensees, and radiopharmaceutical suppliers. 


This information notice advises licensees of recent problems with 
molybdenum-99 (Mo-99) breakthroughs during elution of technetium-99m 
(Tc-99m) because of faulty generators. If the test of eluates is not done to 
determine if a breakthrough problem has occurred, patients undergoing 
medical diagnostic procedures might receive improper medical diagnoses and a
significant radiation dose to the liver, bladder, or kidney from the 
unwanted Mo-99. It is expected that recipients will review the information 
in this notice for applicability to their facilities and consider actions, 
if appropriate, to preclude a similar problem. However, suggestions 
contained in this information notice do not constitute NRC requirements; 
therefore, no specific action or written response is required. 

Description of Circumstances: 

Tc-99m is used for medical diagnostic imaging procedures. Tc-99m is eluted 
from Mo-99 in a device called a generator. When Tc-99m is eluted from a 
faulty generator, some Mo-99 may "break through." Mo-99 is a contaminant 
which has no medical application. Nuclear Regulatory Commission regulations 
require that each elution from a generator be tested for Mo-99 breakthrough.
See 10 CFR 30.34(g). This rule applies to those who elute generators, not to
those who purchase prepared radiopharmaceuticals. 

Recently, two radiopharmaceutical suppliers received faulty generators and 
failed to perform the Mo-99 breakthrough test. Prepared doses were sent to 
several hospitals. Some of the hospitals noted higher than anticipated 
radiation levels from the packages (as a result of the higher energy Mo-99) 
and contacted the supplier for an explanation. Some hospitals did not survey
the packages, or did not realize the significance of higher than "normal" 
survey readings, and patients were injected with contaminated Tc-99m. This 
resulted in unnecessary exposure of patients and workers due to the Mo-99 
breakthrough and the readministration of the intended radiopharmaceutical in
order to perform the prescribed nuclear medicine procedure. The highest 
confirmed amount of Mo-99 in a single dose was 234 microcuries; however, 
unit doses may have been contaminated with up to 100 microcuries Flo-99 per 
millicurie of Tc-99m. 


                                                       IN 84-85           
                                                       November 30, 1984  
                                                       Page 2 of 2        

The NRC limit for Mo-99 contamination is 1 microcurie of Mo-99 per 
millicurie of Tc-99m, not to exceed 5 microcuries Mo-99 per dose (10 CFR 

No specific action or written response is required by this information 
notice. If you have any questions about this matter, please contact the 
Regional Administrator of the appropriate regional office or this office. 

                              J. Nelson Grace, Director 
                              Division of Quality Assurance, Safeguards, 
                                and Inspection Programs 
                              Office of Inspection and Enforcement 

Technical Contact:  Jack R. Metzger 
                    (301) 492-4947 

Attachment:    List of Recently Issued IE Information Notices

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