Using crowdsourced data from shore cleanups, researchers found that areas that enacted plastic bag bans or fees had fewer bags littering their lakes, rivers and beaches than those without them.
At tens of thousands of shoreline cleanups across the United States in recent years, volunteers logged each piece of litter they pulled from the edges of lakes, rivers and beaches into a global database.
One of the most common entries? Plastic bags.
But in places throughout the United States where plastic bags require a fee or have been banned, fewer bags end up at the water’s edge, according to research published Thursday in Science.
Lightweight and abundant, thin plastic bags often slip out of trash cans and recycling bins, travel in the wind and end up in bodies of water, where they pose serious risks to wildlife, which can become entangled or ingest them. They also break down into harmful microplastics, which have been found nearly everywhere on Earth.
Using data complied by the nonprofit Ocean Conservancy, researchers analyzed results from 45,067 shoreline cleanups between 2016 to 2023, along with a sample of 182 local and state policies enacted to regulate plastic shopping bags between 2017 and 2023.
They found areas that adopted plastic bag policies saw a 25 to 47 percent reduction in the share of plastic bag litter on shorelines, when compared with areas without policies. The longer a policy was in place, the greater the reduction.
“These policies are effective, especially in areas with high concentrations of plastic litter,” said Anna Papp, one of the authors and an environmental economist and postdoctoral associate at the Massachusetts Institute of Technology.