In a conversation today, we were discussing nuclear weaponry and radioactivity - Jim C mentioned the radioactivity contained in bananas. I didn't believe him until I consulted the oracle of all things and came up with this paper on banana radioactivity. From the paper:
"Bananas are a good dietary source of potassium. However, 0.0117% of natural potassium is the radioactive isotope 40K.... A large banana (40g) has an activity of about 18.4 Bq (becquerel...) or 0.511 nCi (nanocuries)."
Note that, in terms of raw radiation, this works out to about 0.46 Bq/g.
From this document, depleted uranium has a typical radiation level of about 900 times that - 410 Bq/g.
Given that the always threatened dirty bomb scenario always involves a "grapefruit-sized" amount of depleted uranium, it seems equally likely that a truck-full of bananas would be just as effective in spreading radiation over a large area. (not to mention an incredibly sticky mess)
Is this the next major terrorist threat? Or simply the next piece of security theatre - are we going to start worrying about terrorists armed with Chiquitas