My compressor refer and compressor freezers are set for 35 and -10F respectfully.
Two types of baddies. Bacteria and food poisoning. Food poisoning is just that...residue left by bacteria not the organism itself. You cannot cook it safe.
Down here I have encountered food poisoning mostly with shrimp. Good looking red striped fresh smelling shrimp. Symtoms come on fast and furious. Last eight to 12 hours then depart. Leaves me afraid to go anywhere for a day or two. Chicken is another bothersome media when raw. Irradiated whole milk eliminates a lot of worry but it is not common up north in the states.