The first source said, "Cook food in smokers made of materials approved for contact with meat and poultry. Don't smoke foods in makeshift containers such as galvanized steel cans or other materials not intended for cooking. Chemical residue contamination can result." Is the inside of an old refrigerator approved for food contact? It sure wasn't intended for cooking.
The second source said,
"7.4.2 Zinc coated materials
Galvanized materials and other zinc coated materials shall not be used on surfaces intended for direct food contact.
7.5 Organic (non-metallic) coatings
7.5.1 Direct food contact
Paint and other organic coatings shall not be used on surfaces intended for direct contact with food, except where flouropolymer resin coatings (e.g, polytetrafluoroethylene) are specifically permitted for use under other NSF Standards."
Does anyone know if the paints used in commercial smokers would pass this spec? Does anyone know if the paints used in old refrigerators would?