Kr-85 and Medical Surveillance

["Cappas, Mike" <cappas@mdaw.mdc.com>]

I have two questions I haven't had much luck with finding any answers on my
own:

First, are there any health concerns for inhaled Kr-85. I would assume that it
is excreted rather quickly from the body, but what is its biological half-life?
Is it primarily exhaled? Does it have any specific target organs?

Second, what sort of medical surveillance of radiation workers (radioactive
material and radiographers) is typically done? Although I imagine there is not
much likelihood of detecting anything through medical surveillance when workers
receive very low doses, I would think that about the only thing you can do is
look at the eyes, skin, and blood. It seems like a pre-placement and annual
medical exam is probably a good idea for anyone working around hazardous
materials, but is there anything specific to monitor from a medical standpoint
(with the exception of workers using radioiodine)?

I'd appreciated any information or references someone could give me. Thanks...

Michael Cappas
cappas@mdaw.mdc.com
McDonnell Douglas Aerospace