AIR pollution is killing 3.3 million people a year worldwide, according to a new study.
Scientists in Germany, Cyprus, Saudi Arabia and Harvard University calculated the most detailed estimates yet of the toll of air pollution, looking at what caused it. If trends don’t change, they said, the yearly death total will double to about 6.6 million a year by 2050.
The study, published September 16 in the journal Nature, used health statistics and computer models in its research.
“About three-quarters of the deaths are from strokes and heart attacks,” said lead author Jos Lelieveld at the Max Planck Institute for Chemistry in Germany.
The report’s findings are similar to other less detailed pollution death estimates, outside experts said.
“About 6 percent of all global deaths each occur prematurely due to exposure to ambient air pollution. This number is higher than most experts would have expected, say, 10 years ago,” Jason West, a University of North Carolina environmental sciences professor, told the Associated Press.
“Air pollution kills more than HIV and malaria combined,” Lelieveld said.
With nearly 1.4 million deaths a year, China has the most air pollution deaths in the world, followed by India with 645,000 and Pakistan with 110,000.
The study also surprisingly added that farming plays a large role in smog and soot-related deaths in industrial nations.
The United States, with 54,905 deaths in 2010 from soot and smog, ranks seventh highest for air pollution deaths. What’s unusual is that the study says that agriculture caused 16,221 of those deaths, second only to 16,929 deaths blamed on power plants.
In the Northeast, all of Europe, Russia, Japan and South Korea, agriculture is the top cause of the soot and smog deaths, according to the Nature study. Around the world, agriculture is the No. 2 cause with 664,100 deaths, behind more than 1 million deaths from in-home heating and cooking done with wood and other biofuels.
“The problem with farms is ammonia from fertilizer and animal waste,” Lelieveld said. “That ammonia then combines with sulfates from coal-fired power plants and nitrates from car exhaust to form the soot particles that are the big air pollution killers.”
Lelieveld cited the example of London, where the traffic pollution is converted into soot, “then it is mixed with ammonia and transported downwind to the next city.”
“We were very surprised, but in the end it makes sense,” he said, adding that research 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 was not a part of the study.
Ammonia air pollution from farms can be reduced “at relatively low costs,” Robinson continued. “Maybe this will help bring more attention to the issue.”
In the central US, the main cause of soot and smog premature deaths is power plants. In much of the West, traffic emissions are tragically breaking records.
Scientists and professors including West did dispute the study’s projections that deaths would double by 2050, based on no change in air pollution. West said it’s “more likely” that some places, such as China, will dramatically cut their air pollution by 2050.
Lelieveld said it will be a “win-win situation in both directions” if the world reduces carbon dioxide (considered the main gas causing global warming) because soot and smog levels would go down too.
