The world is burning an alarming amount of plastic, scientists say

Around 12 percent of all plastic waste produced in cities is burned in the open air.

4 min

The world produces around 250 million tons of plastic waste in municipalities in one year — plastic bottles, cigarette butts, plastic packaging and much more. Much of that waste — equivalent to about the weight of 42 Great Pyramids of Giza — is put into landfills; some of it is recycled.

But now, a new study published Wednesday in the journal Nature shows that a large proportion of the plastic waste created across the world is burned in the open air, threatening human health and demonstrating the world’s ongoing struggle to manage its plastic pollution.

“This puts a magnifying glass on what goes wrong” with managing plastic waste, said Costas Velis, a lecturer in civil engineering at the University of Leeds and one of the authors of the paper, in a phone interview.

Twenty-one percent of all plastic waste is unmanaged, according to the new paper — meaning it never makes it to a landfill or recycling plant. A majority of that unmanaged waste, around 57 percent, is burned outside, creating deadly air pollution.

Several countries in the Global South rank among the largest contributors. India’s municipalities burned approximately 5.8 million metric tons of plastic in 2020, while Indonesia burned around 1.9 million tons. Russia also makes it into the top five, openly burning more than 1.4 million metric tons of plastic in the same year.

A spokesperson for the president’s office in Indonesia redirected questions to the Ministry of Environment and Forestry, which did not respond to inquiries on the study. The India Ministry of Environment, Forest and Climate Change also did not respond to a request for comment.

The researchers accumulated detailed data from over 500 municipalities, representing over 12 percent of the global population as of 2015. For each city, they utilized official datasets and surveys to analyze where its plastic waste ends up. They then used machine learning and statistical methods to estimate the fate of plastic in more than 50,000 places around the world.

The result is a detailed inventory of what happens to the millions of tons of plastic waste humans use every year.

Around 1.5 billion people around the world — most of them in the Global South — do not have any city services to collect their waste. Without a government-issued trash system, many of those people bury their plastic waste, dump it in rivers or simply burn it.

Few studies have attempted to account for the plastic that goes up in flames. “We’ve revealed the big importance of the open uncontrolled burning of plastic,” Velis said.

Open burning of plastic has been linked to heart disease, respiratory disorders and neurological problems. Plastic burning generates fine particulate pollution, which has been shown to cause around 7 million deaths per year. It also releases carbon monoxide, hydrogen cyanide and other toxic chemicals that contribute to cancer, birth defects and lung issues.

Despite producing a large amount of plastic waste, the United States has a low rate of burning plastic, thanks to its waste disposal system.

While wealthier countries do send some of their plastic waste to poorer ones, the researchers did not incorporate these shipments into their analysis. They noted that previous work has shown this amounts to only 30,000 metric tons of unmanaged plastic waste each year.

“This study underscores that uncollected and unmanaged plastic waste is the largest contributor to plastic pollution and that prioritizing adequate waste management is critical to ending plastic pollution,” Chris Jahn, the council secretary of the International Council of Chemical Associations, an industry group, said in a statement.

The unmanaged plastic waste that isn’t burned — which ends up in waterways and the environment — also could damage human health. Some harms animals, choking them or entering their lungs and tissues, while other debris is broken down by wind, rain and ultraviolet light. That eventually turns larger plastic pieces into microplastics, which have been found in the air and in the human body with dangerous health implications.

The study comes as nations are struggling to agree on the world’s first international plastics treaty, where some countries favor requiring better waste management and others are pushing for limiting how much plastic a nation can produce.

The researchers hope their study can assist negotiators in identifying which countries are most responsible for dangerous plastic waste — and how to stop it from spilling into the environment or being burned in the first place.

“At that point, it’s too late,” said Ed Cook, a research fellow at the University of Leeds and another author on the paper. “The solutions to try to tackle waste once it’s past the point of emissions are always going to be limited. The horse has already bolted.”

Rebecca Tan contributed to this report.