Why X-Rayed Food Isn't Radioactive and Other Puzzles
"Earlier this week, we were surprised to learn that food manufacturers increasingly X-ray foods to screen for 
foreign objects that can break a tooth. That sounds like a good idea."
"But the notion of X-rayed food also sparked a lively debate in The Salt's comments section on whether this poses a health threat. After all, we do know that some X-rays can damage DNA in the human body. So what does radiation mean for food?"
"To find out, we called around to experts on radiation, food, and safety for their thoughts. First we called Kelly Classic, a radiation health physicist at the Mayo Clinic in Rochester, Minn., and a spokeswoman for the Health Physics Society."