Re: I-125 dose calc formulae? -Reply

[avest@magnus.acs.ohio-state.edu (Albert Lee Vest)]

>>Anyone have I-125 dose calculation math they'd like to share?
>
>If 1 Bq of iodine is ingested, ICRP 30 assumes 0.3 Bq goes to the
>thyroid.  ...
>For reasons that will become obvious we can ignore the iodine outside
>the thyroid.
...
>we have an committed
>effective dose equivalent of 7 E-9 Sv per ingested Bq, also very
>close to whats in FGR 11 (the dose to everything besides the thyroid
>is small potatos). 
>
>Fun stuff:-)

This brings to mind a situation I had a few years ago, when I couldn't
answer questions from certain patients and nursing staff, regarding I-131
ablation therapies.

1) For the patients - they've had most of their thyroids removed already.
They're more concerned about the dose to "everything besides the thyroid".
It may be small potatoes for a 1 Bq intake, but how about drinking 100 mCi?

2) For the nurse in question - Doing a thyroid bioassay was an exercise in
futility, because she had had a thyroidectomy!  Aside from the problem of
measuring uptakes, if any, how would her CEDE be calculated in such an event?

Fun stuff indeed.

Albert Lee Vest           The Ohio State University
Health Physicist    Room 103 1314 Kinnear Road Bldg
(614)292-1284                     1314 Kinnear Road
avest@magnus.acs.ohio-state.edu   Columbus OH 43212
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