Gwalior, Allahabad, Patna, Raipur among world’s most polluted cities
It may be good news for Delhi as World Health Organisation’s urban air quality database for 2016 have shown a decline in PM 2.5 levels in Delhi since 2014, but the same is not true for other cities in India.
According to the report for 2016 released by WHO, India’s Tier 2 and Tier 3 cities, which have far poorer air quality monitoring systems, are among the global cities with the highest levels of particulate matter (PM).
Iranian city of Zabol is the world's most polluted city and is ranked on the top of list released by WHO. The Zabol area is well known for its "120 day wind" a highly persistent dust storm in the summer which blows from north to south.
Gwalior, Allahabad, Patna and Raipur are now world’s 10 most polluted cities. Gwalior with annual average of 176 micrograms per cubic metre (ug/m3) holds second position in the world while Allahabad with annual average of 170 (ug/m3) is on the third place. Whereas Patna 149 (ug/m3) and Raipur (144 ug/m3) are on sixth and seventh position.
|S.No.||City/Town, Country||Rank||PM 2.5|
|4||Riyadh, Saudi Arabia||4||156|
|5||Al Jubail, Saudi Arabia||5||152|
|13||Dammam, Saudi Arabia||13||121|
Comment : Probably some of the worst cities that are the most polluted ones in the world have not been included in the list because they are so bad that they do not even have a good system of monitoring of air quality.
New Delhi, India : Delhi is now the 11th most polluted city in the world, based on average annual PM 2.5 readings of 3,000 cities in 100 countries. The previous WHO report released two years ago that named Delhi as the world’s most polluted city.
The Capital’s pollution slightly improved PM 2.5 concentration falling from 153 micro gram per cubic metre of air in the previous WHO report to 122 but is still six times above the safety limit of 20.
Cause and effect
Too many cars, especially diesel-fuelled vehicles, the heating and cooling of big buildings, waste management, agriculture and the use of coal or diesel generators for power are the most common causes of air pollution .
Tiny particulate matter can cause lung cancer, strokes and heart disease over the long term, as well as triggering symptoms such as heart attacks that kill more rapidly.The WHO says more than 7 million premature deaths occur every year due to air pollution, 3 million of them due to outdoor air quality.