July 15, 2013, 2:27 PM —
Image credit: Flickr/NINAHALE
New research underscores what any rational human being would conclude on their own: Inhaling toxic air over a long period of time is deadly.
But how deadly is what's truly astonishing. The study by an international team of scientists, published in the Environmental Research Letters journal, concludes that more than 2 million people around the world die each year because of polluted air.
"Our estimates make outdoor air pollution among the most important environmental risk factors for health," Jason West, an environmental science professor from the University of North Carolina and one of the study's many authors, said in a statement.
The study team said the "increased concentrations of ozone and fine particulate matter since preindustrial times reflect increased emissions, but also contributions of past climate change."
Researchers created chemistry-climate models for the years 2000 and 1850 (dawn of the industrial era) to determine the impact of outdoor air pollution across the globe. Here's what the team says in the paper's abstract:
Using simulated concentrations for 2000 and 1850 and concentration–response functions (CRFs), we estimate that, at present, 470 000 premature respiratory deaths are associated globally and annually with anthropogenic ozone, and 2.1 million deaths with anthropogenic PM2.5-related cardiopulmonary diseases (93%) and lung cancer (7%).
Air pollution tends to be worse in high-population areas such as China and India.
Two studies released last week also painted a grim picture of air pollution's deadly impact around the world. In a study of lung cancer cases across Europe, researchers concluded that any kind of air pollution is dangerous.
Dr. Ole Raaschou-Nielsen of the Danish Cancer Society Research Center said they couldn’t find a “safe” level of air pollution. The more pollution, the higher the risk, even at legally accepted limits.
The European team looked at data from 17 different studies involving more than 300,000 people in nine European countries. Over 13 years, 2,095 people developed lung cancer.
Researchers determined that an extra five micrograms of soot per cubic meter of air increased the average person's chances of getting lung cancer by 18%.
The second study, published last week in the medical journal Lancet, explored the impact of air pollution on heart failure. Increasing the amount of carbon monoxide by only 1 part per million raises the risk of heart failure by 3.5%, while raising the level of particulate matter by 10 micrograms per cubic meter increases the risk by 2%.