Wazoodle lists its PUL as food safe (but I would ask for documentation). Also, Prym, the maker of Babyville PUL (which you can buy at JoAnn's) apparently will give you a product information sheet saying the BV PUL is food safe. Mostly, I think that means its phthalate, BPA and PVC free.
From my limited research another factor FDA considers are crevices in the "container" that would be hard to clean (ie a bag would have corners/crevices). But I would only worry about this, personally, if selling them.
For personal use, I'd have no problem using the 2 products I listed above. I'm not heating my food up in my bag and I'm mostly using them so I don't have to throw away a gazillion zip locs.
I've made a couple with rip stop nylon inner with a cotton outer.
Actually, just found this:
"Wow, there is lots of excitement in Babyville! Many of you have already found the products and are interested in the product certifications. That's great! Babyville Boutique products have been tested for and either meet or exceed CPSC and CPSIA certified lab testing requirements. You can be assured our products are BPA, PVC and Phthalate free. A certificate of conformity is available at http:/gcc.dritz.com/. You will need the product number or upc code from the package to access these.
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