i don't pretend to know a lot about a lot, but I do think I know just enough about enough, and that includes knowing to always choose organic if the food is grown in the ground, like carrots, potatoes and peanuts.
So I have always bought organic peanut butter for my kids, feeling a bit smug about it all. But a co-worker turned me on to this link -- http://www.deanesmay.com/archives/007598.html -- that details the problems with a mold found in peanuts, aspergillus flavus, one of the types of mold that produces a carcinogen known as aflatoxin. So???
So, the Web site states: (O)rganic" or "natural" peanut butters will have the highest aflatoxin concentration. The highest concentration of all, though, will typically be the stuff you buy in the store where they take peanuts and grind them into peanut butter for you while you wait. Because while the USDA and FDA has rules for how much aflatoxin is allowed in food before it's shipped to stores, there's no measure of it after it reaches the stores. Those peanuts could have been sitting on the shelves at the story for weeks or months at room temperature, building up mold. It's even worse if the air is mildly moist. Furthermore, if you fresh-grind those nuts into peanut butter, the mold keeps growing in the peanut butter."
Yikes! I may have to ask my local health food store how long those peanuts have been sitting around. And maybe even go back to Jif...