Washington: Eliminating emissions from dirty household fuels such as wood, dung, coal and kerosene without any changes to the industrial or vehicle emissions could improve India's air quality standard, claim researchers.
According to the study published in the Journal of Proceedings of the National Academy of Sciences, mitigating the use of household fuels could also reduce air pollution-related deaths in the country by approximately 13%, which is equivalent to saving about 270,000 lives a year.
"Household fuels are the single biggest source of outdoor air pollution in India. We looked at what would happen if they only cleaned up households, and we came to this counter-intuitive result that the whole country would reach national air pollution standards if they did that," said co-author of the paper, Kirk R. Smith.
Americans usually associate air pollution with smokestacks and car exhaust pipes. But in many rural areas of the world where electricity and gas lines are scarce, the bulk of air pollution originates from burning biomass, such as wood, cow dung or crop residues to cook and heat the home, and from burning kerosene for lighting. As of early 2016, nearly half of the Indian population was reliant on biomass for household fuel.
In addition to generating greenhouse gases like carbon dioxide and methane, these dirty fuels kick out chemicals and other fine particulate matter that can stick in the lungs and trigger a whole host of diseases, including pneumonia, heart disease, stroke, lung cancer and chronic obstructive pulmonary disease.
"There are 3,000 chemicals that have been identified in wood smoke, and taken at a macro level, it is very similar to tobacco smoke," Smith said. In 2015, India's average annual air pollution level was 55 micrograms per cubic meter (ug m-3- micrograms per cubic meter of air) of fine particulate matter.
New Delhi by many estimates is the most polluted city in the world, often soared beyond 300 ug m-3. By comparison, fine particulate matter in the San Francisco Bay Area peaked at around 200 ug m-3 during the 2018 Camp Fire. Complete mitigation of biomass as fuel could be achieved through widespread electrification and distribution of clean-burning propane to rural areas.
This action would cut India's average annual air pollution to 38 ug m-3, just below the country's National Ambient Air Quality Standard of 40 ug m-3. "While this is still far above the World Health Organization (WHO) standard of 10 ug m-3, it could still have dramatic impacts on the health of the country's residents", Smith said.
"You can't have a clean environment when about half the houses in India are burning dirty fuels every day. India has got to do other things to fix air pollution -- they've got to stop garbage burning, they've got to control the power plants, they've got to control vehicles and so forth. But they need to recognise the fact that households are very important contributors to outdoor air pollution, too", he added.
"We've realised that pollution may start in the kitchen, but it doesn't stay there, it goes outside, it goes next door, it goes down the street and it becomes part of the general outdoor air pollution....