Actually, that is exactly what happens in 99.9999% of the cases. If my own experience is any guide, toothbrushes getting turned on in luggage must happen a lot.

Actually, that is exactly what happens in 99.9999% of the cases. If my own experience is any guide, toothbrushes getting turned on in luggage must happen a lot. All you need is to have one with a push-button design and forget to take out the batteries. Yet, this is the first I've heard of an airport getting shutdown as a result. The way this sort of incident happens is, some excitable person reports something he considers suspicious. Then the authorities err on the side of caution until they've had a chance to examine the phenomenon first hand. Of course, real bombs don't make noise until they do.