In some cities around the world, just breathing the air can be hazardous to your health. Here is a list of the most air polluted cities to know about – and possibly avoid if you value inhaling. Most international cities that monitor air quality experience pollution levels that are deemed unsafe by the World Health Organization. The WHO says that air pollution is getting worse in many cities around the globe, especially in industrializing countries in the Middle East and Asia. They define air pollution as airborne particles less than 10 micrometers in diameter (PM10). The standard level of PM10 is 60, just to give you an idea of how alarmingly polluted some of these listed cities really are. The values shown for each city are the annual averages of pollution in micrograms per cubic meter of air.
19. Beijing, China
China’s capital city has been experiencing high levels of air pollution for years. Smog often blankets the city and it was so bad in 2013 that the government had to take emergency measures and citizens were advised to stay inside. The main contributors to the city’s poor air quality are exhaust emissions from the city’s five million motor vehicles, burning coal in neighboring regions and the significant storms of dust generated from local construction sites and the north.