Cigar and cigarette smoke, pepperment altoids, and crayons in a hot car. When I was a kid, my parents drove my brother and I up and down the east coast in a VW camper. We would always have crayons and coloring books in the back of the camper to help pass the time away. When those suckers got hot, I always got nauseated(sp). Remember: 1970's + VW camper = NO AIRCONDITIONING! Many summers of travel misery. Even today, I prefer that my DD not take crayons in our van.