Air pollution and its costs travel, which means countries can’t fix this problem alone, according to an article published Thursday in the journal Nature.
The researchers looked in particular at how the human costs of ambient air pollution shift between China and the United States and Western Europe because of nature and the economy.
On the one hand, air contaminated by fine particulate matter in one country can sicken or kill people in another country. The article said that air pollution that originated in China in 2007 was linked to an estimated 3,100 premature deaths in the United States and Western Europe that year.
Globally, some 410,000 deaths in 2007 could be linked to air pollution that began in another region of the world. (In total, 3.45 million people died prematurely from air pollution in 2007.)
On the other hand, international trade can create long distances between where goods are produced and where they are consumed. The researchers concluded that more than 760,000 air pollution-related deaths worldwide in 2007 were tied to the production of goods that would be sold far away. In particular, some 110,000 premature deaths in China that year were tied to consumption in the United States and Western Europe.
“Air pollution can travel long distances and cause health impacts in downwind regions,” Qiang Zhang, one of the co-authors and a researcher at Tsinghua University in Beijing, explained to Popular Science. “Our study revealed that international trade has greatly extended the distance of such impacts by separating the locations of consumption and production.”
By multiple measures, China is particularly hard hit by air pollution. Some 650,000 Chinese died prematurely due to bad air in 2007. (Researchers on this article came from China, Canada, the U.S. and the U.K.)
Despite those figures, Zhang told Science magazine that the point wasn’t for one region to blame its premature deaths on another. Their findings simply quantify “the extent to which air pollution is a global problem in our global economy,” he said.
In 2012, about 1 in 8 deaths worldwide ― 7 million people ― were due to air pollution, according to World Health Organization estimates. Exposure to air pollutants is linked to myriad health problems, including heart disease, stroke, cancer and respiratory illness.
Because exposure is frequently beyond the control of individuals, however, it’s crucial that local, national and international governments work together to protect people. The WHO urges governments to implement policies to lower pollution, such as promoting public transportation and using clean renewable power sources instead of coal.