We had a cat whose very favorite activity was chewing the handles off plastic bags and swallowing them. No plastic bag was safe, and she knew about every new plastic bag that came into the house. She would run away with them just so we couldn't catch her. We were constantly securing plastic bags and making sure they were safely put away or disposed of. Although she has long since gone to the rainbow bridge, even now, I will find myself absent-mindedly picking up all plastic bags, even though our current kitties could care less about them.