Mexico is the Western Hemisphere second large metro area to ban the bags . Move comes as leading environmentalists call for global ban . U.N. agency : China has adopted a strict limit , reducing litter and eliminating the use of 40 billion bags , the World Watch Institute said , citing government estimates . Plastic bags are second -most common form of litter . Bags a major threat to ocean wildlife , the World Watch Institute agency says .
Mexico is the Western Hemisphere second large metro area to ban the bags . Move comes as leading environmentalists call for global ban . U.N. agency : Plastic bags are second -most common form of litter . Bags a major threat to ocean wildlife , the World Watch Institute agency says .