In the 16,000 cities all over the world affected by air pollution, it is New Delhi in India that is hit hardest by its sordid air quality, recording deaths as high as 100 percent since 1991. This is based on the latest report released by the World Health Organization (WHO).
Data showed that New Delhi has an annual average of 153 micrograms of small particulates or PM 2.5 per cubic meter, triggering mortality rates in the city to reach soaring heights that is mainly due to illnesses associated with the dirty air such as cardiovascular and respiratory diseases.
"Too many urban centers today are so enveloped in dirty air that their skylines are invisible," said Dr Flavia Bustreo, WHO Assistant Director-General for Family, Children and Women's Health. "Not surprisingly, this air is dangerous to breathe. So a growing number of cities and communities worldwide are striving to better meet the needs of their residents - in particular children and the elderly."
The findings from WHO were backed up by a study [pdf] conducted by a team of researchers from Indian Institute of Technology (IIT)-Roorkee, University of Minnesota and University of Colorado noting that mortality due to "chronic obstructive pulmonary diseases" (COPD) is caused by air pollution.
In 1991, there were 8,945 cases of deaths in the city of New Delhi alone. A total of 3,413 of them are caused by cardiovascular disease while 1,302 cases are due to respiratory ailments. In sum, around 12,890 residents were admitted to the hospital because they were diagnosed with COPD.
At the turn of the second millennium, the number of total mortality grew to 11,394 and 3,912 of them were cases of cardiovascular mortality. A total of 1,697 cases were due to respiratory illness while the number of New Delhi residents admitted to the hospital rose to 16,253.
More than a decade after, a hundred percent growth was seen. A whopping 18,229 number of deaths were recorded, with 6,374 and 2,701 cases of cardiovascular and respiratory deaths, respectively. Hospital admissions due to COPD plummeted to 26,525.
"From 2002 onwards, the excess number of mortality rate is continually higher in North West district [of New Delhi] because of higher concentration of pollutants and higher population," wrote the researchers led by Bhola Ram Gurjar of the Department of Civil Engineering of IIT. "In 2010, the excess number of total mortality in North West district is 4,035, which is highest among all districts."
The findings were published in the Atmospheric Pollution Research journal.
However, the Indian government opposed the findings, saying that the data has been "overestimated."
"Delhi is not the dirtiest ... certainly it is not that dangerous as projected," A.B. Akolkar, a member secretary of the Central Pollution Control Board of India, told Reuters.
Indian Institute of Tropical Meteorology chief project scientist Gufran Beig added that New Delhi's air was better than Beijing's, especially during the summer and the monsoon seasons. The extreme weather adds to the air pollution in the city as well, he said.
New Delhi is just one of the 13 cities in India that entered the top 20 list of the cities with worst air pollution. WHO revealed Patna, Gwalior and Raipur as cities joining India's capital in the top four.