Thoriate opics and cataracts

["Robert M. Loesch" <loesch@spok.eh.doe.gov>]

Colleagues:

Yesterday, Krista K. Wenzel posted a message inquiring about
studies done to quantify airborne respirable thorium when cleaning
up broken thoriated lens.  I have a related question, does anyone
have any information on the potential eye dose from workers who 
spend most of their day looking thru various types of microscopes.
Are the eyepieces typically not thoriated or, if they are, is there
any hazard to be concerned of?

Bob Loesch

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      _/_/	   _/_/      _/_/_/_/   Robert M. Loesch
     _/	 _/     _/   _/     _/         US Department of Energy
    _/	  _/  _/      _/   _/         EH-52, GTN, 270CC
   _/	  _/ _/       _/  _/_/_/_/   19901 Germantown Road	
  _/	 _/  _/      _/  _/  	    Germantown, MD  20874-1290
 _/    _/     _/   _/   _/         Tel: 301 903-4443;  Fax: 301 903-7773
_/_/_/        _/_/     _/_/_/_/   loesch@spok.eh.doe.gov
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 "The definition of a public health disaster is a catastrophe so large
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