A new study finds that regional plastic bag bans in the U.S. significantly reduce coastal plastic bag litter compared with areas without such policies. Single-use plastic bags are one of the most ubiquitous forms of plastic litter. They are rarely recycled and degrade quickly into microplastics that are often ingested by wildlife, leading to injury, stress and death. To tackle the problem, many municipalities have turned to regulation. As of 2023, roughly one in three U.S. residents lived in an area with some type of plastic bag policy: Ten states  enacted laws to ban plastic bags or charge a fee to discourage their use, another two states enacted such policies in 2024. More than 90% of policies are at the local town level. Meanwhile, more than 100 countries have some type of ban or fee on thin plastic bags. Despite the widespread adoption of plastic bag policies, there have been limited data on their effectiveness, until now. To fill this gap, study authors Anna Papp, an incoming postdoc at MIT, U.S.,  and Kimberly Oremus, an associate professor at the University of Delaware’s School of Marine Science and Policy, turned to crowd-sourced beach cleanup data collected between 2016 and 2023 by the nonprofit advocacy group Ocean Conservancy. Through its app called Clean Swell, which records trash picked up by volunteers, the NGO has collected long-term, standardized data from more than 226,000 locations globally. “The volunteers, when they gather their litter, they count and categorize the items and enter that into the app,” Oremus…This article was originally published on Mongabay