State and local policies to regulate the use of plastic bags have significantly reduced how many of them are found littered along U.S. shorelines — potentially cutting that type of waste in half in certain places, a new study published Thursday in the journal Science found.
More than 600 bag policies, along with records from more than 45,000 shoreline cleanups between 2017 and 2023, were reviewed by researchers to see whether implementing bans or fees on plastic bags led to fewer discarded bags found near coastlines, rivers and lakes – and if they did, to what extent.
Co-authors environmental economist Anna Papp and Kimberly Oremus, a marine science and policy professor at the University of Delaware, found that the number of plastic bags collected as shoreline litter in places with bag policies dropped by at least 25%, and up to 47% over six years than in locations that did not have regulations.
“When we found the database that had information on different shoreline cleanups, we realized we could look at the composition of litter before and after a policy to see what effect it had,” Oremus said in a statement. “And then we could compare that to places that never got a plastic bag policy.”
These results bring fresh insights to an issue that gained prominence over the last decade or so, as awareness spread about the harms of plastic pollution and its threats to marine environments. Oremus said it’s the first attempt to comprehensively review the effectiveness of plastic bag policies on shoreline litter, using a database of global shoreline cleanup initiatives from the nonprofit Ocean Conservancy.
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Since 2018, more than 100 countries around the world have implemented some form of policy to either ban or limit the use of plastic bags, according to a report by the United Nations Environment Program. The U.S. doesn’t have a federal bag policy, but individual towns, cities and states have policies of their own.
Some states, like New York, have completely banned retailers from distributing plastic bags. Others, like Washington, passed partial bans in recent years, where thinner plastic bags deemed “single use” are prohibited, but thicker plastic bags are not. Oremus and Papp noted in the study that, although those thicker bags are usually considered “reusable” under partial bans, “there is evidence that some consumers still treat them as single-use.”
In multiple states without bans, local jurisdictions such as counties have taken steps to regulate plastic bag use. For example, Arlington County, Virginia, requires stores to collect a fee from customers who purchase plastic bags, at 5 cents per bag. But 17 states prevent plastic bag regulations even at the county level, with statewide “preemption” laws in place to ensure the distribution of these bags isn’t regulated at all.
During the study period, plastic bag litter was collected less often in shoreline cleanups that took place in areas where some form of regulation existed to curb their distribution and use, the authors said.
“Our findings make clear that plastic bag policies have been broadly effective in limiting—but not eliminating—shoreline plastic bag debris in jurisdictions where it was previously prevalent,” Oremus and Papp wrote in the study. They also found evidence that suggests fees on plastic bags are more effective at limiting shoreline litter than bans, especially partial bans, but understanding why would require more research.
