The World Health Organization — which has previously found that indoor and outdoor air pollution killed a shocking 7 million people globally in the year 2012 — released a new analysis on Tuesday underscoring the extent of the risk, which seems to grow worse and worse the more we learn about how damaging tiny airborne particles can be to our health.
Most strikingly, the new report, which combines local data with a global model to determine the extent of deadly air pollution across the planet even in places where there are no instruments recording it, finds that 92 percent of people suffer under pollution levels that are worse than WHO standards (as of 2014). The vast majority of deaths are in developing countries. The document calls air pollution the “largest environmental risk factor.”
Of greatest concern is a form of pollution called PM2.5, referring to particles smaller than 2.5 micrometers. The global health agency believes that a concentration greater than 10 micrograms per cubic meter of these fine particles in the air qualifies as dangerous. The great risk is that the particles are so small that they can be inhaled, travel into the lungs, and enter the bloodstream.
“People think of air pollution as a respiratory disease,” said Carlos Dora, who heads the WHO’s air pollution team. “And in fact, it’s heart disease, strokes and cardiovascular. Because there’s very small particles that go into the blood … the damage air pollution does to the vessels is similar to the damage that cholesterol or high blood pressure do. That has changed a lot the picture.”
He said it is becoming clear that there are few causes of death that take a larger toll each year, including malaria and tuberculosis. The new report credits air pollution with “about one in every nine deaths annually.”