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I spoke with a sales manager of a wheat starch manufacturing plant.  He
has a son with a wheat allergy and one of the office manager's has a
husband with celiac.

He did not want to go in to too much detail.  But I did obtain from him that
they make wheat starch and wheat gluten at his plant.  He told me that
the following items may contain wheat starch (these are just the few
items he was willing to share with me):

Sheet Rock  (Drywall)  (Now I know why it makes my throat itch!!)
Carbon Paper
Potable Alcohol (which, is commonly used in drinkable alcoholic
   beverages, and according to my contact, is often purchased by
   companies which manufacture vinegar) (Not surprising) (Although more
   often it is made with corn)
Ethanol
Sugars (he did not say what kind)
Alcohols

He also told me that he has many businesses he sells to, who refuse to
reveal the use of the wheat starch and wheat gluten.  These clients
have told him, basically, that if he wants their business, it is none of his
business what they are making with the wheat products they purchase
from him.  This was discouraging news.  Everybody who works with
wheat knows that those of us with CD need to know what contains
wheat, yet some businesses try their hardest to keep us ignorant.  I
wonder what else is made with wheat which we are unaware of
because of such secretiveness?
Abigail