Twenty-one of the world’s 30 cities with the worst air pollution are in India, according to data compiled in IQ Air AirVisual’s 2019 World Air Quality Report, with six in the top ten.
Ghaziabad, a satellite city of the capital New Delhi in northern Uttar Pradesh state, is ranked as the world’s most polluted city, with an average PM 2.5 concentration measurement of 110.2 in 2019. That’s far more than double the level which the US Environmental Protection Agency regards as healthy — it’s nine times more.
And in November, a public health emergency was declared after the air quality index (AQI) level exceeded 800 in certain parts of New Delhi, which was more than three times the “hazardous” level.
Researchers from IQ Air — a global air quality information and tech company — gleaned data for the report from on the ground monitoring stations that measure levels of fine particulate matter, known as PM 2.5, per cubic meter.
However, South Asia has seen improvements from the previous year. National air pollution in India decreased by 20% from 2018 to 2019, with 98% of cities experiencing of varying levels of improvement. The report points to economic slowdown, favorable weather conditions, and efforts towards cleaning the air as reasons behind the decrease.
For example, the most polluted city, Ghaziabad, had an average AQI of 110.2 this year. But in 2018 it was 135.2 and 144.6. in 2017. (Source:CNN)