Air pollution in India led to half a million deaths in the country in 2011, a new study published in the journal Geophysical Research Letters said. Nearly 570,000 premature deaths in India occurred due to exposure to PM 2.5 (particulate matter, which is an air pollutant and measures less than 2.5 microns in size). The study said that 12,000 people died by developing chronic obstructive pulmonary disease (COPD) due to ozone exposure.
It added that the northern and eastern part of the country (Indo-Gangetic region) were the most affected and accounted for 42 percent of the total deaths. The average life expectancy of Indians came down by 1.1 to 3.4 years, and for people living in Delhi, the air pollution resulted in the decline of life expectancy by 2.2 to 6.3 years.
The economic burden due to premature deaths by air pollution was estimated at $640 billion in 2011, which is 10 times the public and private health expenditure in India, the study said.
The study took into account census 2011 data and relied on computer simulations of outdoor air pollution levels across the country.
The researchers then calculated the number of premature deaths from air pollution, based on the previous data of human responses to pollution levels.
India has surpassed China in terms of air pollution levels with the Indian capital, Delhi, being the most polluted city in world.
According to World Health Organization, the PM 2.5 levels of Delhi were reported to be of 153 micrograms per cubic meter (µg/m³), which is three times the pollution level in Beijing, China and 10 times the average pollution levels in New York.
The smaller size air pollutants (PM 2.5), according to the National Research Development Corporation (NRDC), are not blocked well by the human body and can lead to serious respiratory diseases and even heart failure. People who live in cities with high PM 2.5 have more heart attacks, depressed lung function, worse asthma, and die younger than people who breathe clean air, according to NRDC.
Long-term exposure to these fine particles emitted from vehicles could lead to premature deaths as a result of chronic obstructive pulmonary disease (COPD), ischemic heart disease (IHD), stroke and lung cancer.
A study conducted by the Indian Institute of Technology (IIT), Delhi, had earlier said that 2.79 lakh Indians die prematurely because of COPD, 1.1 lakh die of IHD, while 88,700 and 14,800 deaths are caused by stroke and lung cancer, respectively. The study was also based on the levels of PM 2.5 in air.
A United Nations report said that 7.3 million deaths occurred due to air pollution in Southeast Asia and the Western Pacific regions in 2012, whereas 12.6 million people die every year due to unhealthy environments.