In a newly published study, researchers at NCAR revealed that 40 percent of the world's garbage is disposed of in this reckless and toxic fashion -- much more than official statistics let on -- most of it in developing countries where landfills and incinerators are few and far between.
"Air pollution across much of the globe is significantly underestimated because no one is tracking open-fire burning of trash," Christine Wiedinmyer, NCAR scientist and lead author of the new study, explained in a press release. "The uncontrolled burning of trash is a major source of pollutants, and it's one that should receive more attention."
To estimate the amount and types of trash fire emissions, researchers at NCAR looked at official totals of trash disposal for each country in the world. They then studied human consumption patterns in countries most prone to these sorts of trash fires to see what types of things were most likely being burned.
In the end, Wiedinmyer and her colleagues were able to estimate that trash burning is responsible for nearly a third of all emitted small particulates (less than 2.5 microns in diameter) -- the particles that make up smog and soot and make places like Los Angeles, Beijing and New Delhi difficult to go running on hot, still days. The researchers also pinned 10 percent of mercury emissions and 64 percent of the release of a group of gases known as polycyclic aromatic hydrocarbons (PAHs) on unregulated trash burning. These pollutants have been linked with asthma, lung disease, cancer, heart attacks and worse.
"This study was a first step to put some bounds on the magnitude of this issue," Wiedinmyer said. "The next step is to look at what happens when these pollutants are emitted into the atmosphere—where are they being transported and which populations are being most affected."
The study was published last month in the journal Environmental Science & Technology.