In six months, San Francisco will become the first North American city to ban plastic bags. It’s likely that Mayor Gavin Newsom will approve the legislation which was voted in by San Francisco’s Board of Supervisors. The city, which uses 181 million plastic bags annually is set to save 450,000 gallons of oil a year with this move, as well as eliminating the 1400 tons of plastic bag waste currently sent to landfills.