Outdoor air pollution killed 0.65 million Indians in 2010: study

Of the 3.3 million premature mortality worldwide in 2010 caused by outdoor air pollution, about 0.65 million deaths took place in India. These deaths were in adults older than 30 years and in children younger than five years.

India has the second highest premature deaths caused by outdoor air pollution. With 1.35 million deaths annually, China ranks number one in the world.

A study published on Thursday in the journal Nature has for the first time taken into account the data from highly polluted regions like Asia for estimating the global mortality caused by air pollution.

At 0.32 million, more than half of premature mortality due to outdoor air pollution in India was from residential energy used for heating and cooking. Power generation was the second biggest culprit causing nearly 90,000 deaths in 2010. At 42,000, industry and biomass burning caused equal number of deaths, followed by 30,000 deaths from land traffic in India.

Of the seven sources of outdoor air pollution, residential energy use is the most important category that causes the most premature deaths worldwide. “It contributes to one-third of premature mortality globally,” J. Lelieveld, the first author from the Max Planck Institute for Chemistry, Mainz, Germany, said in a press briefing. “Residential energy use is an inefficient form of fuel combustion that causes lot of smoke and is by far the most important cause of premature mortality in Asia.”

Emissions from residential energy use, together with waste disposal and diesel generators, contributes to 32 per cent deaths in China but 50-60 per cent in the case of India, Bangladesh, Indonesia and Vietnam.

The estimate of 1 million premature deaths globally due to emissions from solid fuel and also waste disposal and diesel generators is in addition to the 3.54 million deaths per year due to indoor air pollution from the same sources.

According to Kalpana Balakrishnan, who is not connected with the study and is the Director of the WHO Collaborating Centre for Occupational and Environmental Health at Sri Ramachandra University, Chennai, there were one million deaths in India in 2010 due to household air pollution from solid fuels.

Air pollution is associated with many health impacts. “Strokes and heart attacks are responsible for nearly 75 per cent of air pollution-related mortality,” said Dr. Lelieveld.

On the basis of model projections, the authors predict that premature mortality from outdoor air pollution could double by 2050 on the basis of projected rates of increase in pollution and population levels, with 6.6 million premature deaths forecast globally per year, including large increases in Southeast Asia and the western Pacific.

While 1 million lives can be saved globally every year by reducing ambient exposure to pollution, about 3.54 million lives can be saved annually by lowering indoor exposure to PM2.5 emissions, notes Michael Jerrett from the University of California, Los Angeles, in an accompanying news article.

“The improved chulhas, which are supposed to be smokeless, provide very little health-relevant exposure reduction,” Dr. Balakrishnan said. “That is because solid fuel can’t be burnt in relatively inexpensive stoves. There is compelling evidence to move towards cleaner fuels than cleaner chulhas.”

Published in The Hindu on September 17, 2015