Donna Carlton (where?) asks:

>>I am interested in information regarding radioactivity used in the lymph 
node procedure for breast tissue. I have been assured by radiology that the 
hazard after 24 hours is minimal.<<

I suppose you refer to sentinel lymph node biopsy using technetium 99m sulfur 
colloid to mark lymph nodes. I think this topic has been addressed on 
Histonet before, but I may be thinking of the pathology list.

Technetium 99m (Tc-99m) is a short-lived (6 hours) gamma emitter. The short 
answer to this question is - it wouldn't matter if you ATE the specimen when 
you received it. Ordinary gloves and dissection technique provide more than 
adequate protection.

The long answer, unfortunately, is that radiation safety rituals may require 
the specimen be stored for ten half-lives (60 hours) before you may touch it. 
This is clearly neither acceptable histologic practice nor are surgeons going 
to put up with it.

Sentinel node biopsy is a clinically useful technique for breast cancer and 
melanoma, but it takes so much of the surgeon's and the OR staff's time that 
it isn't at all clear that the procedure is practical, and it may not be with 
us for much longer.

Bob