Comment on "Short essay on plutonium"

[TOOHEYR@ORAU.GOV]

The essay states:

     Since plutonium is an alpha particle emitter the Annual Limit on 
     Intake is based on critical organ dose rather than on whole body
dose. 

This is misleading; the ALI is based on dose to bone surface because the
tissue weighting factor is less than 0.1 (actually 0.03); thus one could
exceed 0.5 Sv to the organ without exceeding 50 mSv EDE; being an
alpha emitter has nothing to do with it.  Same thing goes for iodines,
because thyroid weighting factor is also 0.03. 

Hate to nitpick, but it comes with the infernal dosimetry business.

Dick Toohey
Radiation Internal Dose Information Center
TooheyR@ORAU.GOV