First they banned smoking. Some are trying to ban trans fat. Next on the list of possible forbidden things in cities: plastic bags.

Boston city councilors are talking about ridding the city of plastic shopping bags, by banning their use at grocery and other retail stores. They litter the streets, clog landfills, but they are oh so convenient so naturally business groups are not too thrilled. Nine of the 12 sitting councilors are supporting the measure, but Mayor Menino would need to sign off on it.

San Francisco has apparently already banned the bags and others are thinking about it.

It’s interesting to see cities across the country taking the lead on a variety of environmental issues, like climate change and energy efficiency. New York City earlier this week announced an ambitious plan to “green” the city and lower greenhouse gas emissions. And I’ve blogged here about Boston’s and Cambridge’s efforts as well. Seems like they’re stepping up to the plate now that the federal government doesn’t appear to be taking any kind of leadership role. Going green, it seems, will have to happen at the grassroots level.