Ludhiana, Kanpur among world's top 10 cities with worst air pollution

New Delhi: Some of the world's largest and most densely populated cities have air that is so polluted that people suffer from lung diseases at rates that are significantly above global averages. Birth defects in these cities are also at extraordinarily high levels, as are heart disease and cancer rates. Many of these cities are among the fastest-growing in the world. And in some, residents burn wood and coal for warmth, releasing additional deadly pollution into the atmosphere. Here are the ten most polluted cities in the world:1. Ahwaz, Iran This Iranian city tops the list of most polluted cities. With a whopping 372ug/m3, it is by far the worst air of any city in the world. Again, it's an unhealthy combination of duststorms and factory emissions. The city also suffered a series of bombings in 2005, related to the war in Iraq. 2. Ulaanbaatar, Mongolia In Ulaanbaatar, the annual average particulate matter concentrations are 14 times higher than WHO's recommended level. The city's poor air quality has caused high incidences of chronic bronchitis and cardiovascular diseases. A thick smog often blankets the city, and at times daytime visibility is so poor that cars must use their headlights. 3. Sanandaj, Iran Another Iranian city that is suffering from both dust storms and heavy industrialization, the air pollution here is 254ug/m3. However, the Iranians are keen to shift the blame onto the American forces in neighboring Iraq, who have destroyed the agriculture there and so have caused the dust storms. 4. Ludhiana, India With a high air pollution measure, this is another place that faces serious problems in the near future. The Punjab Pollution Control Board (PPCB) blames the auto-rickshaws for the pollution, as they run on enviro-unfriendly diesel. Air is not the only problem in Ludhiana – the river is also extremely polluted, thanks to run-off from the dyeing industries. 5. Quetta, Pakistan This city has a measure of 251 ug/m3, making it the most polluted city in a fairly polluted country. Local reports call it a “serious environmental issue for human health” and a panel of experts met in the city after the 2011 index came out, to formulate their “Action Plan for Reducing Air Pollution and Improving Air Quality Management in Quetta City”. 6. Kermanshah, Iran With an air pollution index of 229 ug/m3, this is another Iranian city with a serious pollution problem. Traditionally an agricultural center, the city is fast becoming industrialized with 256 manufacturing units within the city, including Kermanshah Oil Refining Company which was established in 1932 by the British. Industries today include sugar refining, petrochemicals and electrical equipment all of which are starting to overwhelm the city. 7. Peshawar, Pakistan This Pakistani city is the second most polluted in the country at 219 ug/m3, beating the capital Lahore which can be found in eleventh place. Reports from 2006 showed the city at sixth place and “getting worse”, despite the government taking anti-pollution measures. Clearly the measures were ineffective, given how polluted the air still is. Part of the problem is the auto-rickshaws that clog up the streets and belch out fumes. 8. Gaborone, Botswana According to local sources, the pollution is at its peak in the month of May and drops during August and September. Various causes of the pollution are cited, including imported cars and people cooking over paraffin stoves and even animal dung. 9. Yasouj, Iran One of four Iranian cities to appear in the top ten this is an industrial city, with a sugar processing plant and a coal-burning power plant which both contribute to the score of 215 ug/m3. There are also plans to build a refinery there, which will only exacerbate the problem. 10. Kanpur, India This industrial city was once known as the “Manchester of the East”, so it doesn't immediately fill you with visions of green meadows and clear waters. But the reality is grimmer than most imagined before the WHO results were published – Kanpur is the second most polluted city in India with a score of 209 ug/m3. It's the leather capital of the region, with a large tannery but it also has steel factoriesand many other industries.