<<Disclaimer: Verify this information before applying it to your situation.>> I just learned the hard way about cross contamination of rice flours. Last week I tested a brown rice flour from my local Co-op that stated it was wheat and gluten free. I reacted to it, so I checked into the source and after a few calls talked to the manufacturer who said that they don't have dedicated milling equipment for rice so cross contamination is possible. Though they clean the machines in between runs. Next, I went to a Chinese food distributor and tested rice flour from Thailand, should be far enough from the wheat fields of the USA. The distributor had packages of both glutinous rice flour and regular rice flour. Well, the flour was very sticky and definitely had gluten in it. This week I after feeling sick for 4 days and having difficulty in finding the source of my problems, I came to the conclusion that my white rice flour from Arrowhead Mills probably was contaminated. I talked to quality control at Arrowhead Mills today and they confirmed my suspicions, they do not have dedicated milling equipment for the production of rice flours. I don't know if everyone is this sensitive to wheat gluten but from now on I am only going to buy flours from rice only manufacturers like Ener G foods (I don't have stock in the company). I talked to them today and their equipment is for rice only. For breakfast I usually eat organic health food cereals some of which contain rice flours. I haven't noticed a reaction to these so I must be able to handle some gluten. I think it is next to impossible not to ingest gluten to some degree. Just to play it safe though, next time I'm behind the bakery truck on the freeway on the way to work, I am changing lanes. Paul Groschen St. Paul, MN