Air pollution is a growing problem killing over 3 million people each year in large cities and “wreaking havoc on human health,” says the World Health Organization. On Thursday, the WHO said four out of five city dwellers worldwide live in cities that do not meet its air quality guidelines.Air Pollution Hurting Millions And Growing At An 'Alarming Rate'

Air pollution becoming a death agent

These are the findings of WHO’s third Global Urban Ambient Air Pollution Database. This database studies outdoor air in 3,000 cities, towns and villages across 103 countries. It is based on data from country reports and other sources.

“Ambient air pollution, made of high concentrations of small and fine particulate matter, is the greatest environmental risk to health — causing more than 3 million premature deaths worldwide ever year,” the UN health agency said.

In a press release, the health agency noted that during the period, global urban air pollution increased 8%, though improvements were seen in some of the regions. As air quality gets worse, people are more prone to lung cancer, respiratory diseases, strokes, and heart disease.

The Director of Environment and Public Health at WHO, Dr. Maria Neira, stated that air pollution in urban areas is growing at an “alarming rate,” but a positive development they observed is that awareness is also rising “and more cities are monitoring their air quality. When air quality improves, global respiratory and cardiovascular-related illnesses decrease.”

According to the database, Zabol, Iran is the most polluted city with the highest annual mean concentration — a key measure of air pollution — of particulate matter of less than 2.5 microns in diameter. Though India was not at the top of the list this time, more than half of the 21 most polluted cities on the WHO list were from India.

India: some improvement but still plenty to worry

New Delhi, which topped the list previously, bagged the ninth spot this year. From 2014 to 2015, this Indian capital was able to lower its annual average concentration of particulate matter by 20%. New Delhi has taken several measures in the past few years to curb air pollution, like closing an old coal-fired power plant, banning older cars and cargo trucks from the city, and levying heavy fines for construction pollution or garbage burning. But overall, the condition is still quite bad in the country.

According to the WHO data, four other Indian cities – Raipur, Gwalior, Patna and Allahabad – overtook New Delhi to rank as the second, third, fourth and fifth most polluted cities worldwide. WHO applauded the efforts of the cities and policymakers to encourage more efficient energy, better waste management and cleaner transportation.

“More than half of the monitored cities in high-income countries and more than one-third in low- and middle-income countries reduced their air pollution levels by more than 5 percent in five years,” the UN health agency said.

Another nation plagued by air pollution is China, but it has improved its air quality since 2011. Now only five of its cities are in the top 30 polluted cities. In the U.S., the most polluted city is the inland city of Visalia-Porterville in California, while in Australia, it’s Geraldton, a major seaport on the west coast north of Perth.