WHO: Iran, South Asia Ranked Worst in Urban Air Pollution

Tiny particles are floating in the air. You breathe them in every day. They enter your lungs and, if they’re small enough, they can go directly into your bloodstream. Not all of them are harmful, but like most substances, certain types can become hazardous at higher rates. They can cause heart disease, lung cancer, asthma and other life-threatening diseases and conditions. These tiny particles can kill, and in cities all over the world, the amount of them in the air is rising.

A new report from the World Health Organization looking at data from about 1,100 cities worldwide finds that average levels of particulate matter in the air are about 3 and a half times higher than WHO air quality standards. The report analyzes data on PM10 particles, particulate matter in the air that measures 10 micrometers or less. At this size, particles can easily enter the bloodstream. The WHO recommends an annual average of 20 micrograms per cubic meter as an acceptable level. The global average is 71 micrograms. The worst air quality was reported in Ahwaz, Iran, with reported average levels of 372 micrograms. Other cities at the bottom of the list include Lahore, Pakistan, Ludhiana, India and Ulaanbaatar, Mongolia, each with levels above 200 micrograms.