Tertiary butylhydroquinone, or TBHQ, helps oily foods last on shelves longer. TBHQ contains butyl which is in the same chemical family as butane, the stuff in lighter fluid, but it is not butane. However, the FDA limits the amount of TBHQ companies can place in food. One gram of TBHQ could make you nauseous or cause fainting, according to LiveStrong.com. But you'd have to consume buckets full of candy at once to ingest one gram of it.
So when you see the word "lake" behind the name of a dye, that means the color is mixed with a metal compound to keep the colors from running. These M&M's contain Blue 1 Lake, Yellow 5 Lake, Red 40 Lake, Yellow 6 Lake and Blue 2 Lake. The FDA limits the amount of mercury, arsenic and lead permitted in those colors.