Massachusetts is considering taxing them. Reno is talking about banning them. Plastic shopping bags are increasingly popular targets of governments looking for ways to help the environment. "It's a small, simple, modest act that makes people feel that they're actually contributing" to reducing litter, waste and dependence on foreign oil, says Supervisor Ross Mirkarimi, sponsor of San Francisco's ban on petroleum-based plastic bags in big grocery stores. Since that ban — the USA's first — took effect in November, he says, there's been a noticeable decline in plastic-bag litter and "a sea change in the habits of consumers," many of whom now tote reusable bags. New York City and California require some retailers to recycle plastic bags. Industry groups such as the American Chemistry Council prefer that approach. Plastic bags require at least 40% less energy to make than paper and produce less than half the greenhouse gases, says ACC's Sharon Kneiss. Plastic bags can be recycled into construction materials, decking and more bags, she says. The group says Americans use about 90 billion plastic bags a year. Paper bags are easier to recycle, the Sierra Club says, and the equivalent of 11 barrels of oil is saved for every ton of plastic bags reused or recycled. It recommends reusable bags. Ireland started taxing plastic bags in 2002; within weeks, usage dropped more than 90%. China's ban on free plastic bags takes effect June 1. In the USA: •Massachusetts state Sen. Brian Joyce introduced a bill that would charge consumers 2 cents for every plastic bag, gradually increasing to 15 cents over seven years. Half the revenue would go to the store to improve consumer awareness and half would go to state recycling programs. "It's designed to be a gentle nudge to consumers to change their behavior," he says. •Connecticut is considering a bill that would fine retailers up to $1,000 if they use non-biodegradable plastic bags beginning in 2010. Stan Sorkin, executive director of the Connecticut Food Association, says his group "is really pushing mandatory recycling programs for plastic bags" instead. •In Reno, city environmental services administrator Jason Geddes is researching options that include a ban and recycling incentives. "There's a lot of interest and … community buzz," he says. •In Maryland, legislation that would ban plastic bags in all grocery stores might not make it out of committee this session, but its sponsor, Delegate Todd Schuler, says he'll reintroduce it. "It's going to be a long campaign," he says. •An energy committee in Valparaiso, Ind., is considering ways to reduce plastic-bag usage, including the possibility of a small tax. "Those bags are made from petroleum-based products and they travel a lot of miles to come to us and we use them in abundance," committee member Ann Kenis says. Conversation guidelines: USA TODAY welcomes your thoughts, stories and information related to this article. Please stay on topic and be respectful of others. Keep the conversation appropriate for interested readers across the map.