- India could make a major dent in air pollution and save about 270,000 lives a year by curbing emissions from ‘dirty’ household fuels such as wood, dung, coal and kerosene. But in order to achieve National Ambient Air Quality Standards (NAAQS) compliance all across the country, sources beyond the household sector need to be controlled, experts said.
- Despite aggressive programs to provide clean energy to households, significant challenges remain in ensuring sustained use of clean fuels in households.
- Another study that looked at the pathways for managing future air quality in India underscores that more than 674 million Indian citizens are likely to breathe air with high concentrations of particulate matter (PM2.5) in 2030, even if India were to comply with its existing pollution control policies and regulations.
- The most important drivers of air pollution, such as household fuels, power plants and waste burning, draw less public concern than sources such as vehicular emissions, according to a public perception study.
Aggressive mitigation measures to promote clean-fuel usage across all household sources, not just cooking, would help bring down the ambient particulate matter levels (PM2.5) within safe limits in India and reduce air pollution-associated premature deaths, a study has said.
‘Dirty’ household fuels (such as wood, cow dung, coal and kerosene) are the single biggest source of outdoor air pollution in India, where, as of early 2016, nearly half of the population was reliant on biomass for household fuel.
Household air pollution is responsible for approximately one million premature deaths every year in India – particularly women and young children.
Among all household sources, cooking, followed by space heating, water heating and lighting, is the largest contributor to outdoor air pollution, according to the analysis led by researchers at the University of California, Berkeley and the Indian Institute of Technology Delhi.
The percentage contribution of household sources toward outdoor PM2.5 levels exceeds 40 percent in most of the districts in the Gangetic basin, while in the southern and central states the contribution is below 30 percent.
“The Indian government has initiated programs such as Pradhan Mantri Ujjwala Yojana (to provide LPG to poor households) and the Deen Dayal Upadhyay Grameen Jyoti Yojana (providing electricity to all rural households) to reduce household use of biomass cooking fuels,” explained Sagnik Dey of IIT Delhi.
“But their guiding principle does not include reducing pollutants in the air surrounding us. India is not realising the full benefits of providing clean household fuels considered in national policies, which would include benefits to the households themselves from lower pollution exposures as well as lower outdoor pollution levels,” Dey said.
The outdoor (ambient) air pollution is measured by annual average concentration of particulate matter smaller than 2.5 micrograms or PM2.5. The average annual PM2.5 concentration of 40 micrograms per cubic metre is the safe limit for PM2.5 as prescribed by the National Ambient Air Quality Standards or NAAQS.
The modelling study looked at controlling household sources across various scenarios for the base year, 2015.
In an ideal scenario (complete mitigation of household emissions), if all households transitioned to clean fuels, India’s average annual air pollution would come down to 38 micrograms per cubic metre, just below the country’s safe limit of 40 micrograms per cubic metre (the NAAQS limit).
The move could bring down air pollution-related deaths in the country by approximately 13 percent, which is equivalent to saving about 270,000 lives a year, the analysis said.
Complete mitigation of biomass as fuel could be achieved through widespread electrification and distribution of clean-burning propane to rural areas.
The ideal scenario would also push 103 additional districts out of a total 597 districts (equivalent to 187 million people) to meet the Indian annual air-quality standard compared with the 2015 baseline when 246 districts (398 million people) met the standard, added Dey.
Achieving the hypothetical ideal scenario could result in avoiding 13 percent of the all-India premature mortality burden.
In 2015, India’s average annual air pollution level was 55 micrograms per cubic meter of fine particulate matter and more than half the Indian population (about 670 million citizens) was exposed to PM2.5 concentrations that did not comply with India’s NAAQS for PM2.5.
Achieving comparatively pragmatic scenarios (such as slashing 75 percent of all emission from residential cooking and lighting and 50 percent of all emission from space and water heating in a district are eliminated) could avert eight percent of the total premature mortality burden.
A moderate scenario, where 50 percent of the residential cooking and lighting is phased out and 25 percent of space and water heating is eliminated, could avert an estimated five percent of the deaths.
The results support the expansion of programs designed to promote clean household fuels and rural electrification to achieve improved air quality at regional scales, which also has substantial additional health benefits from directly reducing household air pollution exposures, said Dey.
“These policies can be upgraded and revised to incorporate the health benefits,” Dey told Mongabay-India.
Referring to Pradhan Mantri Ujjwala Yojana (PMUY) and the Deen Dayal Upadhyay Grameen Jyoti Yojana, Dey, however, said the problem lies in execution – there is no further effort to ensure uptake and access to these services at the ground level.
However, despite aggressive new programs to provide clean energy to households, significant challenges remain in ensuring sustained use of clean fuels in households that receive an LPG stove and in ensuring reliable and consistent electricity supplies to displace kerosene lamp usage, the authors write in the study.
Pallav Purohit, a researcher at IIASA’s Air Quality and Greenhouse Gases programme, who was not associated with the analysis, said it is important to differentiate between the mean annual average PM2.5 exposure for India and NAAQS-compliance everywhere.
He agrees with the findings of this study that controlling emissions due to solid fuel (fuelwood, agricultural residues, dung, coal) use in residential/household sector by providing access to clean fuel (LPG/electricity) will significantly improve India’s air quality.
“However, this does not mean that we will have NAAQS-compliance across the country (including Indo-Gangetic Plains). Therefore, in order to achieve NAAQS-compliance everywhere, sources beyond the household sector need to be controlled,” Purohit told Mongabay-India.
This, Purohit said, is reflected in Dey’s study that says districts that are out of attainment (NAAQS compliance) could be assisted by enforced policies to limit agricultural crop waste and open trash burning and to control industrial emissions among other emission sources.
Purohit’s own research with co-authors at IIASA and the Council on Energy, Environment, and Water (CEEW), New Delhi, underscores that more than 674 million Indian citizens are likely to breathe air with high concentrations of PM2.5 in 2030, even if India were to comply with its existing pollution control policies and regulations, including ones pushing clean fuels.
The study which looked at different pathways for managing future air quality in India shows that only about 833 million citizens would be living in areas that meet India’s NAAQS in 2030 and that implementation failure could increase these numbers significantly.
However, aligning sustainable development policies to the implementation of advanced emission control technologies could provide NAAQS-compliant air quality to about 85 percent of the Indian population.
“At the sectoral level, we agree that residential combustion is the major source for primary PM2.5 emissions whereas, at the state level, we agree with Dey’s article that most of the southern states are under NAAQS compliance for the base year 2015,” explained Purohit.
Purohit’s study assumes that as a consequence of the successful implementation of the PMUY to provide clean cooking fuel to households, biomass will be entirely replaced by alternative cooking fuels by 2040.
“Therefore, in 2030, we will have biomass in our baseline scenario. Our emission inventory for 2030 indicates that the residential combustion sector contributes approximately 38 percent of the total primary PM2.5 emissions,” he said.
In the context of these findings, Dey and Purohit stressed on enhancing public perception and awareness on household air pollution effects and prevention for adding momentum to the switch to clean fuels.
“One of the most important steps in the prevention of household air pollution is education, especially spreading awareness among people about the issue and the serious threat it poses to their health and wellbeing,” reiterated Purohit.
According to ‘Hazy Perceptions’, a new study from global health organisation Vital Strategies, analysis of news and social media from a three-year period shows poor public understanding of air pollution’s major causes and the most promising solutions.
The report underscored that public discourse does not centre on the most important drivers of air pollution, such as household fuels, power plants and waste burning, draw less public concern than sources such as vehicular emissions.
CITATION
Chowdhury, S., Dey, S., Guttikunda, S., Pillarisetti, A., Smith, K. R., & Di Girolamo, L. (2019). Indian annual ambient air quality standard is achievable by completely mitigating emissions from household sources. Proceedings of the National Academy of Sciences, 201900888.
Banner image: Use of firewood for cooking for school students in West Bengal. Photo by Shankar Sarkar/Greenpeace.
