Diatomaceous Earth (D.E.)

[Biciclista]

so what you are saying is that there is SAND in Diatomaceous earth (Silica) and the food grade would have (most of) the sand removed. Interesting.

[OakLeaf]

??? I thought diatomaceous earth WAS silica - the exoskeletons of diatoms. What else is it???

[Eden]

I gather you need to be sure to get food grade because of two reasons - one food grade comes from fresh water sources, no one explains why salt water sources are bad, but I would guess it has some sort of undesirable contaminants, and because non-food grade often has toxic substances added - so you wouldn't want to ingest the stuff that is sold for filtering pools.

Silica itself isn't toxic, thought it is drying and you can kill buggies that are sensitive to dehydration with DA and it does carry a warning about breathing it in - it is fine enough to cause silicosis (black lung disease).

I figure I probably eat enough dirt riding around here in the winter... I don't think I need to add any to my diet intentionally...

[SadieKate]

From what I know about DE, I certainly wouldn't take it long term. Yeah, there is foodgrade DE that is generally considered safe by the FDA, but I don't think it goes beyond that.

Foodgrade is mostly used as a de-wormer for livestock.

I was raised by a mother who did drug development in her early career and we were taught to treat the bug-killing powder with the utmost care.

http://en.wikipedia.org/wiki/Diatomaceous_earth

There was a huge controversial mess here a few years back when some developer decided he wanted to build houses on an abandoned diatomaceous earth mine.