Fresno had an outbreak of food poisoning in 1999, and it wasn’t accidental. Seems labor and management had a falling out, and about 100 Fresnans got an unexpected dose of “…methomyl, a highly toxic agricultural pesticide that can be handled and bought only with a permit”, per the CNN report.
 
Your humble correspondent lived in Fresno then, and I have a vague remembrance of the establishment being closed down, but at the time the rumor was of a more natural food poisoning, not chemical warfare on patrons. Had I been working in an ED on that end of town I would probably remember it more vividly.
 
So, look for happy employees in the kitchen, too.
