Food contamination is when something makes the food inedible or can cause illness when consumed. Contamination can be   # Biological (bacteria, parasites, viruses, etc.) …  # Chemical (cleaners, sanitizers, additives, etc.)  # Physical (glass, metal, etc.)   Contamination is not necessarily obvious or visible.ood cross contamination is basically food poisoning. If you cooked 2 different raw things together, your mixing 2 nasty raw things together and cross contaminate. Get it, contamination as like when you mix 2 different things together and cross as in 2 or more things.