I'll never get why people look specifically for food-grade chems, it's like they are paranoid about chemicals. food-grade means FCC (Food Chemical Codex) compliant, which is based on USP standards (typically ACS-grade chemicals).
so moral of the story is: if you are that anal about getting "food grade" chems, just get ACS-grade, and use safe practices. you're preparing
drugs, not salad.
"Nothing is true, everything is permitted." ~ hassan i sabbah
"Experiments are the only means of attaining knowledge at our disposal. The rest is poetry, imagination." -Max Planck