Those of you mentioning potassium nitrate, are any of you using a pure source? I ordered some food grade potassium nitrate from a lab with the intention of combining it with beetroot extract. (Just a cheaper version of a great NO supplement I was given to try that showed a huge increase in available NO via saliva test.) However, even though the potassium nitrate I got is food grade, the label is covered with dire warnings against breathing or ingesting it. I assume that, dosed correctly, this food grade potassium nitrate is exactly the same as what's in potassium nitrate-containing supplements and is safe to mix with beetroot in water and consume? Or is an agonizing death imminent?