(CNN)UNICEF is calling on world leaders to reduce air pollution, saying it leads to the deaths of more children yearly than malaria and HIV/AIDS combined. Around 600,000 children under age 5 die every year from diseases caused by or exacerbated by outdoor and indoor air pollution, especially in poor nations, UNICEF Executive Director Anthony Lake said in the introduction to a report titled "Clear the Air for Children."

This city’s air pollution is five times worse than Beijing’s. ULAANBAATAR — If you think air pollution in China has been bad, just look at Mongolia. Levels of particulate matter in the air have risen to almost 80 times the recommended safety level set by the World Health Organisation