Researchers in marine plastics pollution say the U.S. ranks high among nations responsible for plastics debris, revising their previous study that some had interpreted to place the blame more on five countries in Asia.
A 2015 study that said the five countries in Asia account for more than half of the plastics in oceans is frequently mentioned in plastics pollution debates along with official documents like U.S. Environmental Protection Agency documents and congressional testimony.
The authors now say that study is no longer true, if it ever was.
A new study published Oct. 30 in the journal Science Advances backs away from the earlier research and estimates the U.S. could rank as high as third among ocean plastics emitters, up from 20th in the older study.
What changed, they say, is what they were able to measure. The new estimates for the first time include the substantial impact of U.S. plastic scrap recycling shipped overseas that ultimately can't be properly recycled and materials that are illegally dumped within the U.S.
The authors, including prominent researchers Kara Lavender Law and Jenna Jambeck, challenge "the once-held assumption" that the United States adequately manages its plastic waste, according to a news release.
In 2016, the U.S. had 4 percent of the world's population but accounted for 17 percent of all plastic waste, according to the study. And U.S. residents generate almost twice as much plastic waste per capita than residents of the European Union.
"As the largest producer of plastic waste in the world, the United States must simultaneously act to reduce the amount of plastic waste we generate and take full responsibility for its reprocessing and its ultimate disposal," said Law, a research professor of oceanography at the Sea Education Association in Woods Hole, Mass.
The previous study blaming five Asian countries — China, Indonesia, the Philippines, Thailand and Vietnam — has taken a prominent spot in public dialogue.
As one example, an Oct. 19 news release from EPA specifically says those five countries contribute more than half the ocean plastic waste. It was made as part of an announcement for a new U.S. strategy on reducing marine litter. The statement is in the full report as well, with a citation to the 2015 study.
Members of Congress and industry sometimes cite that 2015 research in their public comments, as has President Donald Trump. In the new EPA strategy report, Trump is quoted saying he wants to "stop other nations from making our oceans into their landfills."
Authors of the new research say their findings have implications for government policy.
"I would not use that language about the top five countries anymore, because there is new information available that is changing our picture," Law said.
She said the 2015 study was the first to try to quantify the amount of plastic leaking from land into the oceans, an important exercise but also inherently "squishy" given different data collection by different countries and difficulties measuring.
"[The 2015 study] was not intended to be a finger pointing, sort of rank-the-bad-people exercise," Law said. "You could completely redo that study again, and you would get different results."