[Histonet] Re: Radioactive substance

[John Kiernan]

I checked Bob Richmond's half-life figures in
Lange's Handbook of Chemistry. As expected, 
Bob R. is spot-on. It is wonderful that such
low levels of radioactivity can be detected,
measured, and used to estimate future 
surgical intervention. It's also good to 
know that the specimens are not dangerously
radioactive by the technetium.
-- 
-------------------------
John A. Kiernan
Department of Anatomy and Cell Biology
The University of Western Ontario
London,   Canada   N6A 5C1
   kiernan <@t> uwo.ca
   http://publish.uwo.ca/~jkiernan/
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RSRICHMOND <@t> aol.com wrote:
> 
> Rita Humphrey asks: >>Would anyone please share your procedure for handling sentinel nodes removed in surgery that have been treated with radioactive substance?<<
> 
> We've discussed this subject on Histonet several times, though not very recently. Sentinel lymph nodes are labeled with technetium 99m sulfur colloid. The amount of radioactive material present in the lymph nodes - or in the subsequent lumpectomy specimen - does not require any special handling beyond the usual precautions. Radiation safety people may impose restrictions, but from an viewpoint of actual safety they are unnecessary.
> 
> Technetium 99m has a half-life of six hours. It emits a gamma particle and becomes technetium 99, which has a half life on the order of hundreds of thousands of years. The minute amount of it present is not considered hazardous.
> 
> To put it very crudely: you could eat the specimen and nothing much would happen to you from the radioactivity.
> 
> Bob Richmond
> Samurai Pathologist
> Knoxville TN