Once again in the latest issue it is stressed that DE from swimmng supply stores should not be used for human or animal consumption. Could somebody please explain why? The OSHA fact sheet didn't indicated any additives, and it's surely the cheapest place to get it if one doesn't live within driving distance of a supplier.

-- glynnis (gabbycab@aol.com), December 28, 1999

Answers

The reason is because swimming pool diatomaceous earth has been heat treated to sharply increase the crystalline silicate content of the filtering agent. This increase is enough to present a much more serious inhalation hazard than non-heat treated diatomaceous earth, as well as being a hazard to being blown into your eyes. You don't want to be inhaling the non-heat treated DE either(or wheat flour dust, for that matter) but it's much less of a hazard.

Unless you're storing tons of grains five pounds of DE will more than do you for a long time and it's cheap enough to mail order.

I explain DE, its use, precautions and alternatives in the FAQ as well as list a number of possible sources, if you're interested.

.........Alan.

The Prudent Food Storage FAQ, v3.5

http://www.providenceco-op.com

-- A.T. Hagan (athagan@netscape.net), December 28, 1999.

Alan, I read your FAQ on the subject and it appears that you have covered the subject well. Thanks for having it on line.

-- greenbeanman (greenbeanman@ourtownusa.net), December 28, 1999.

I understand that the treatment that is given to the swimming pool DE for filter use also reduces it's effectivness as an insect control agent as it reduces the sharp edges on the DE particles that damage the insects.

Jim

-- Jim (jiminwis@yahoo.com), December 30, 1999.