Air quality index (AQI) is used to determine how polluted the air currently is or how polluted it is forecast to become. Public health risks increase as the AQI rises.
Air pollution continues to pose one of the biggest threats to human health, with 90% of the global population breathing unsafe air.
In South Asia, Indian and Pakistani cities again dominate the world’s most polluted cities for PM2.5 in 2019. Twenty-one out of the top 30 most polluted cities are located in India. Five of the top 30 most polluted cities are located in Pakistan.