[freedude]

My Grandpa used to say if a child didn't eat a pound of dirt a year it just wasn't healthy. This was usually in response to my Aunt's frenetic diatribe about a cousin getting dirty while on the farm.

He was right. We got dirty on the farm. We ate dirt in the form of working and playing in the dust and mud. We would get "cleaned up" on the hot summer days by swimming in the river. Not only did we survive, we thrived. It was some of the greatest years of my life, eating a pound of dirt a year...

[hermitcrab]

I worked on developing compartmental modelling software for consultants to use, so they could estimate how radionucleides moved around the environment. One of the parameters the consultants had to work out for their model was - how much dirt does a child eat in a year. I don't know what figure they ended up with.