Examining the five second rule

Is a food still safe if it is picked up off the floor quickly (within 5 seconds to be precise)?

Well, I was catching up on posts on the Curious Cook by Harold McGee and apparently someone at Clemson State decided to find out. According to McGee's NY Times article, the food is contaminated upon contact, although it will be contaminated the longer it sits on the floor.

In practice, the problem is that you don't know if the floor is contaminated, what it is contaminated with, or how much it is contaminated. So is it really safe? This may take more than 5 seconds to figure out.

This post is dedicated to my friend Dan who just taught my son the 5 second rule this week(Thanks for the lesson, eh! :-P ).