Are McDonald's coffee cups microwave safe?

Answer:
Bottom of cup marked recyclable "PS 6".

Type 6 - Polystyrene, styrene, polystyrene foam
Not heat stable. Do not use in microwave. Do not microwave food in a styrofoam container! In addition to not being heat stable, polystyrene is a potential human carcinogen and usually contains bisphenol A.

http://www.scn.org/~bk269/plastics.html
First answer by ID1181183676. Last edit by User102938. Contributor trust: 0 [recommend contributor recommended]. Question popularity: 4 [recommend question].