Tyler,It depends on how close you are and how big the bomb is.
A conventional nuclear weapon relies on nuclear fision this reaction will cause incalcuable damage.
A so called dirty bomb relies on a conventional explosive device with radioactive material surounding it(no fision).There is an excellent example of
the effect of a dirty bomb in Brazil.I will try and find it.Only around 30 people died in an area of a quarter of a mile.more died from the blast than
by radiation.I'm writing this from memory so I may be wrong on detail.I'll be back.
John is more or less correct, dirty bombs are little more than a panic attack, as for the Iodine, hmm from what I've dug up, I should HOPE there is
radio-active Iodine (I-131), it seems to be fairly helpful in aiding the treatment of hyperthyroid (some ailment) and does not promote cancer.
And I think your half-life information is wrong, apparently after treatment (done at home by drinking it) it can collect in your bladder (the
radio-active materials) so you have to drink a lot of fluids for several weeks to wash it all out.
tyler, why specifically iodine? i would think that wrapping a bomb in radioactive waste is a sure-fire way to make a nasty little device, but why the
specific interest in iodine?
An iodine bomb would be extremely weak compared to the dirty bombs the US government is expecting. They are looking for dirty bombs using spent fuel
rods etc.