Good ideas - I like the open container contaminating the food idea.
There was a movie that took place in a jungle. Wish I could remember the title. Anyway. They found a cure for a disease, and tried to retrace the steps as to the ingredients. There was a stalemate. UNTIL they saw ants walking across the ingredients. Formic acid from the ants. Huh. Isn't nature fun.

formic acid (HCO2H), the simplest of the carboxylic acids, used in processing textiles and leather. Formic acid was first isolated from certain ants and was named after the Latin formica, meaning “ant.” It is made by the action of sulfuric acid upon sodium formate, which is produced from carbon monoxide and sodium hydroxide.









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