Six most polluted cities in world | Where do you stand?With pollution becoming an increasing concern for climate change, a real-time report by IQAir shows the top five most polluted cities in the world.According to the report by the Swiss air quality technology company, till 9:21 pm, three Indian cities ranked in the top five of the most polluted cities in the world.According to environmental experts and an earlier report by the Food and Agriculture Organisation, pollution is caused mostly by the transport sector and industries, and not just crop burning. Trans-boundary pollution is also not the main reason as the Met Department has confirmed that Punjab primarily experiences a westerly wave during winter.The rankings may change as per the real-time evaluation.