As citizens gasp for clean air, what is the government doing?
Furhan Hussain moved to Islamabad seeking fresher air, only to find Pakistan's leafy capital in a semi-permanent haze.
Frustrated, he joined a vanguard of citizens monitoring pollution themselves amid a void in government data.
Fast-growing Pakistan is home to some 200 million people and suffers from some of the worst air pollution in the world, thanks to the giant population plying poorly maintained vehicles on the roads and unchecked industrial emissions.
Countries such as India and Sri Lanka publish statistics or warnings to help citizens cope when air pollution goes to dangerous levels.
But Pakistan is "one of few countries who do not monitor air quality", says Hussain, of the informal PakAirQuality network, a group of concerned citizens monitoring pollution in Islamabad, Lahore and Karachi then publishing their data on Twitter.