Indian Cities Dominate World’s Worst Polluted List, 2019 World Air Quality Report Analysis Reveals
With incessant urbanization and industrialization, the global air quality has dangerously deteriorated over the past few years. The recently released World Air Quality Report 2019 revealed that cities in south Asia are most polluted in the entire world. 21 out of the world’s 30 cities with worst air quality are in India, with six in the top 10.
Several major cities in the Indian subcontinent have always dominated the list of world’s cities with worst air pollution. Despite being the national capital, Delhi is among the cities with the worst air quality. In November 2019, the Air Quality Index (AQI) level exceeded 800 in certain parts of New Delhi, prompting the government to declare a public health emergency in the city.
South Asia has 27 cities of the 30 most polluted cities in India, Pakistan and Bangladesh. Ghaziabad, a Delhi suburb, has been ranked as the world’s most polluted city, with an average AQI of 110.2 in 2019.
That is more than double the level which the US Environmental Protection Agency regards as healthy. Gujranwala, Faisalabad and Raiwind in Pakistan are among the ten most polluted cities. Major cities including Delhi, Lahore, and Dhaka rank 5th, 12th, and 21st respectively.
Cities across Asia — including Chiang Mai, Hanoi, Jakarta and Seoul — saw an increase in PM 2.5 levels. Since 2017, Jakarta saw pollution increase by 66%, making it the worst in Southeast Asia. In Thailand, Chiang Mai and Bangkok both saw a number of extremely polluted days — some of which led authorities in the capital to close schools — resulting from construction, diesel fuel and crop fires in surrounding regions.
National air pollution in India decreased by 20 percent from 2018 to 2019, with 98 percent of cities experiencing different levels of improvement.
However, China has made improvements from the previous year. Beijing – once infamous for its toxic haze – has reduced smog levels and dropped down a list of the world’s most polluted cities, falling to 199 from 84 three years ago.
Although several Chinese cities – including Shanghai – saw improvement in air quality, Kashgar and Hotan in the western Xinjiang region were among the world’s worst. Meanwhile, India still dominates its list of the smoggiest urban areas, accounting for 14 of the top 20.
Researchers from IQAir – a global air quality information and tech company – obtained 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.
The microscopic particles, which are smaller than 2.5 micrometers in diameter, are considered particularly harmful as they are small enough to enter deep into the lungs and cardiovascular system.
PM 2.5 includes pollutants such as sulfate, nitrates and black carbon. Exposure to such particles has been linked to lung and heart disorders and can impair cognitive and immune functions.
The report also points to India’s launch of the country’s first National Clean Air Programme (NCAP) which aims to reduce PM 2.5 and the bigger particulate PM 10 air pollution in 102 cities by 20-30% by 2024 compared to 2017 levels.
According to the World Health Organization, air pollution causes an estimated 7 million premature deaths a year globally, mainly as a result of increased mortality from cardiovascular diseases, cancers and respiratory infections.
According to a recent study in the Lancet, the toxic air kills approximately 1.2 million Indians each year.