The World Health Organization (WHO) announced in a press release that the global air quality is deteriorating in my cities across the world. According to the WHO database -- which covers 1,600 cities across 91 countries -- a mere 12 percent of people live in cities that comply with WHO air quality guideline levels.

“Too many urban centers today are so enveloped in dirty air that their skylines are invisible,” said Dr Flavia Bustreo, WHO Assistant Director-General for Family, Children and Women's Health, in a WHO news release. “Not surprisingly, this air is dangerous to breathe. So a growing number of cities and communities worldwide are striving to better meet the needs of their residents - in particular children and the elderly."

From Latin America, eight countries made the list of top 50 countries with the worst air pollution, with Peru being the worst of all Latin American nations. Specifically: Colombia tied in 38th place with a PM2.5 level of 24 ug/m3, Venezuela tied with a PM2.5 level of 26 ug/m3, Mexico tied with a PM2.5 level of 27 ug/m3, also in 30th place was Bolivia with a PM2.5 level of 27 ug/m3, Chile tied in 27th place with a PM2.5 level of 28 ug/m3, the Honduras ranked as the 23rd worst for air pollution with a PM2.5 level of 32 ug/m3, Guatemala tied in 21st place with a PM2.5 level of 33 ug/m3, and Peru ranked 18th with a PM2.5 level of 38 ug/m3.

Despite earning a spot on the top 50 list, the Latin American nations fared better than most other countries in the world. In terms of cities, Delhi was found to have the highest level of the airborne particulate matter, with a PM2.5 level of 153 ug/m3 followed by another Indian city, Patna, with 149 ug/m3. In fact, half of the top 20 cities in the world with the worst air were in India, while other cities that were on the top 20 list were in neighboring South Asian nations of Pakistan and Bangladesh.

Earlier this year, WHO revealed that 7 million people die globally from air pollution each year, making it the "single largest environmental health risk." The U.N. health agency states that air pollution has been linked with heart disease, stroke, chronic obstructive pulmonary disease, and lung cancer.