Unfortunately, the only safe way to buy uncontaminated bulk food is to not do it! Since anyone can put their little fingers in that bin, and since you can swipe a scooper from one bin to another, it simply isn’t safe.
But we can buy bulk pre-packaged foods. Nature’s Path for one, sells bulk or family sized cereals. There are still small ways to save on some of these things. I buy the tiny packages of rice flour, but from the chinese market, they are $.99 each. For about 8 cups! That’s pretty good in my neck of the woods.
Unfortunately I steer clear of the bulk aisle altogether. But, we get to save in other ways on the gluten-free diet. We eat fresh, and not pre-packaged most of the time. Fresh fruit, fresh meat, etc. This saves a ton $. 
Here’s to your health,
Cathy
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