I was at a party once, and some woman said to me, 'You're a scientist, you know all about radiation. How much radiation is in a banana?' I said, 'A banana has about 1/1000th of a milligram of radium in it.' She said, 'Oh my God, I'm never eating a banana again!' I said, 'Well, you're getting more radiation from the concrete floor you're standing on.'
Quantum electrodynamics