Washington – Air pollution is known to kill about 3.3 million people a year worldwide and the rates could double to 6.6 million people a year by 2050 if the trends don’t change, according to a recent study released on Thursday on Nature journal.

The researchers at the Max Planck Institute for Chemistry in Germany are responsible for the study, led by Jos Lelieveld which until date stands for the most detailed estimates of the toll of air pollution. It worked by using a global atmospheric chemistry model to investigate the link between premature deaths and seven emission source categories in urban and rural environments.

Credit: OneGreenPlanet

It was revealed that farming plays a large role in smog and soot deaths – soot includes little black particles composed of carbon as a result of incomplete combustion of fossil fuels chiefly in industrial nations – causing 16,221 deaths. But in countries like the United States the main cause of soot and smog is power plants with 16,929 deaths while in the West, the main contaminant is traffic emissions. So, at global scales, how much deaths is air pollution responsible for?

“About 6 percent of all global deaths each year occur prematurely due to exposure to ambient air pollution. This number is higher than most experts would have expected, say, 10 years ago,” said Jason West, a University of North Carolina environmental sciences professor who wasn’t part of the study but praised it, as reported by  U.S. News.

Researchers estimated that about three-quarters of the deaths are from strokes and heart attacks. An interesting fact is that air pollution kills more than HIV and malaria combined, Lelieveld also said. Some topic of discussion was the study’s projections that deaths would double by 2050 if no change in air pollution occurs. Experts believe that some place in the East like China will most probably cut their air pollution by that time.

Lelieveld said that climate change and air pollution go hand-in-hand, pointing that if the world was to reduce carbon dioxide, the main gas causing global warming, both soot and smog will be reduced as well, leading to a win-win situation.

Who has it worse?

China ranks highest in the air pollution poll with 1.4 million deaths a year, followed by India with 645,000 and Pakistan with 110,000. The United States ranks seventh with 54,905 deaths for air pollution.

In the U.S. Northeast, all of Europe, Russia, Japan and South Korea, agriculture ranks as the No. 1 cause of the soot and smog deaths, according to the study. Worldwide, agriculture is the No. 2 cause with 664,100 deaths, behind the more than 1 million deaths from in-home heating and cooking done with wood and other biofuels in developing countries.


According to Lelieveld, the reason farming is included in air pollution rates is because of the fertilizer and animals wastes produced. They release ammonia that then combined with sulfates from coal-fired power plants and nitrates from cars exhaust soot particles. This particles are the big air pollution killers.

“We were very surprised, but in the end it makes sense,” Lelieveld said. He said the scientists had assumed that traffic and power plants would be the biggest cause of deadly soot and smog.

Agricultural emissions are becoming increasingly important but are not regulated, said Allen Robinson, an engineering professor at Carnegie Mellon University, who wasn’t part of the study but praised it.

Ammonia air pollution from farms can be reduced “at relatively low costs,” Robinson said. “Maybe this will help bring more attention to the issue.”

Source: Max Planck Institute for Chemistry