Packaging: Minneapolis and St. Paul have banned plastic food packaging by 1992 unless it is recyclable or degradable. Portland, Ore., will ban polystyrene (used in coffee cups and hamburger holders) as of Jan. 1, 1990. Beverage yokes: Federal law requires all six-pack loop connectors - which entangle animals, birds, and fish - to be degradable. The Environmental Protection Agency will issue regulations and deadlines by fall 1990. Grocery bags and cartons: Florida has banned plastic-coated milk cartons and nondegradable grocery bags, while setting in place mandatory recycling statewide. Recycling: Several states - Rhode Island, New Jersey, Pennsylvania, Connecticut - have made recycling mandatory; hundreds of municipalities have instituted voluntary, curbside recycling. Pending in Congress: Legislation introduced by Sen. Albert Gore Jr. (D) of Tennessee and Rep. George J. Hockbrueckner (D) of New York calls for government and industry to work together to increase recycling and in five years to make nonrecyclable plastics into degradables.