ISLAMABAD, June 11: Air pollution level in the country's populated cities is the highest in the world and causing serious health issues, Economic Survey of Pakistan (ESP) 2003-04 shows.

The level of ambient particulates -- smoke particles and dust, which cause respiratory diseases -- are generally twice the world average and more than five times as high as in industrial countries and Latin America, it says.

According to a study carried out by the federal ministry of environment, about 16.28 million people, 40 per cent of the total urban population of the country, are under risk of air pollution, which is costing Rs25.7 billion on account of health merely by not complying with World Health Organization's Ambient Air Quality Standards.

"Auto and industrial emissions are the main source of dirty air. The average compounded growth of vehicles in the country is about 12 per cent per annum and over the last two decades, the total number of motor vehicles on the road has jumped from 0.8 million to almost 5.0m, an overall increase of more than 600 per cent."

The combustion of coal is another main contributor to air pollution. The three main uses of coal are power, brick kilns and for domestic purposes. However, since 1998-99, coal use has been decreasing gradually in all the three sectors and is being replaced by natural gas.

During July-March 2003-04, 3,173 million cubic feet of natural gas was supplied per day as against 2648 million cubic feet per day during the same period last year, showing an increase of almost 20 per cent.