The peaks and troughs of India's quest for clean air
Only 15 of 131 cities meet the national air quality safety standards, according to data presented in the Parliament. Here's an on-ground assessment
Data and documents tabled in the recently concluded winter session of the Parliament by the ministry of environment, forests and climate change (MoEFCC) paint a mixed picture of the crucial battle against the climate crisis. A series of documents on air quality control were put forward, offering a comprehensive evaluation of cities that fell short of the National Ambient Air Quality Standards, assessed in 2023 against the base year 2017.
The documents also detailed the funds allocated for air pollution control under the National Ambient Air Quality Monitoring Programme (NAMP) and the 15th Finance Commission. Additionally, it included data on annual average particulate matter (PM10) levels from 2020 to 2023 and, notably, introduced projects aimed at assessing the impact of air pollution on human health in 20 selected cities nationwide.
The National Clean Air Programme (NCAP) was launched in 2019 with the aim to reduce particulate matter (PM) concentration by 40% by 2025-26. It focuses on 131 cities across 24 states and Union territories, marking a significant step in India's commitment to addressing air pollution.
NCAP member Professor SN Tripathi, who heads the civil engineering department and is joint faculty in sustainable energy engineering at IIT-Kanpur said the programme offered “a solid framework to emphasise three areas,” namely, “informing science by generating data; sectoral-level reforms pushing towards mitigation; and, interlinking departments to focus on pollution abatement.”
“There has been some progress on all the fronts. However, the actual improvement will come in the near future when the initial framework will be built upon by adding more capacity, creating and expanding the monitoring network, and pushing mitigation measures into core sectors of business, transport and industry,” he said.
Air pollutants are gaseous (sulphur dioxide, nitrogen oxides, ozone, among others) and solid particulate matter (PM), which can easily enter the lungs and bloodstream and cause serious ailments. The ultrafine PM is PM1 and PM2.5 with diameters less than 1 and 2.5 microns; PM10 has diameters less than 10 microns. The major sources of PM are vehicular emissions, biomass burning, solid waste burning and dust from roads, soil, and construction works. PM10 is identified as the lead pollutant under the NCAP — 60 micrograms per cubic metre (µg/m3) is the annual average safe limit.
Air Quality across India this year
Out of the 131 targeted cities, only 15 met the National Ambient Air Quality Standards for PM10. Not one of them met the World Health Organization's more stringent norms (15 µg/m3).
Fifty-one of the 131 cities showed a 20% or more improvement in PM10 concentrations compared to the base year (2017-18). However, only four cities — two in Uttar Pradesh (Varanasi 59%, Firozabad 57%), one each in Tamil Nadu (Tuticorin 56%) and Uttarakhand (Dehradun 53%) — achieved an over 50% improvement, indicating that the pace of change is not uniform across the country.
Some regions witnessed a decline in air quality. Visakhapatnam in Andhra Pradesh and Vasai-Virar in Maharashtra saw an alarming increase in PM10 concentrations – by 52.63% and 56.57%, respectively.
“In all, 90 cities out of 131 cities have shown improvement in air quality in terms of annual PM10 concentrations with respect to the baseline of 2017-18. This goes to show that we are well on our way to achieving the 40% target by 2025-26. Monitoring of sources at the city, airshed, and at the local level is being done. There has been capacity building of urban local bodies across all 24 states and UTs over the past five years,” a senior official from the Union environment ministry, requesting anonymity.
Anumita Roychowdhury, executive director, Centre for Science and Environment (CSE), said a detailed report on city-wise air quality performance was needed. “Any report card on air quality performance of cities should mandatorily provide details on the exact nature, scale, and magnitude of source-wise interventions and the comprehensiveness of the action,” she said, as it would help identify gaps in source-specific pollution control measures, as well as facilitate a culture of cross-learning among cities for effective impact.
Regional disparity in air quality
The story of air quality improvement in India is not even. Some states have made significant strides while others have lagged. Several cities in Uttar Pradesh and Uttarakhand have seen a notable improvement, a majority in Madhya Pradesh and Odisha have witnessed deteriorating air quality.
Andhra Pradesh presents a mixed picture. Cities like Anantapur and Chittoor have seen improvements exceeding 25%, while Visakhapatnam has seen a steep worsening, as mentioned above.
In Assam, Guwahati and Nagaon have observed a decrease in air quality, but Sivasagar has shown noteworthy improvement. Bihar, on the other hand, has seen a uniform deterioration across all its cities, including Patna and Gaya.
Chandigarh has experienced a slight dip in air quality in Punjab, while in Chhattisgarh, Durg Bhilainagar has shown improvement, and Korba and Raipur have seen a decline.
Delhi has registered a 13.28% improvement in PM10 levels. According to Tripathi, the improvement is visible based on the substantial monitoring network developed in the city. “Measurements provide representative data in space and time whereas in other cities where the network is sparse (monitoring stations range between 1 - 3 in each city), measurements do not provide a representative pattern of the city,” he said.
Divergent trends in PM pollution
Aerosols, as a class of air pollutants, encompass solid particulate matter (PM10 and PM2.5), representing a range of microscopic particles suspended in the atmosphere with significant environmental and health impacts.
A recent independent study conducted by the Bose Institute, Kolkata, under the Department of Science and Technology, Government of India, provides a nuanced perspective in comparison to the data submitted in Lok Sabha. This study highlights the complexities of aerosol pollution in India, indicating that while there is significant improvement in PM10 levels, as reported by MoEFCC in Lok Sabha, the challenge of managing finer aerosols like PM2.5 remains. The findings call for tailored strategies that address the unique pollution sources and dynamics of each region.
To be sure, the discrepancy in the two sets of data can be attributed to rigorous measures undertaken by state governments post-2018.
Titled ‘A deep insight into state-level aerosol pollution in India: Long-term (2005–2019) characteristics, source apportionment, and future projection’ (2023) by Monami Dutta and Abhijit Chatterjee from Bose Institute, the study utilised satellite-retrieved aerosol pollution data, focused on fine-mode aerosols (PM 10 and PM2.5). The study projects a general increase in particulate matter pollution up to 2023 across various Indian states. These projections, based on a business-as-usual scenario, suggest an increase ranging from 2% to 24% compared to 2019 levels.
"Our study contrasts sharply with the data submitted in the Parliament focused on urban non-attainment cities under the NCAP," said Chatterjee, associate professor department of chemical sciences, Bose Institute.
The study reveals that in the Indo-Gangetic Plain (IGP), all states except Punjab are projected to experience a minimal increase in aerosol pollution, mainly due to crop residue and solid fuel burning. "This contrasts with the data shared before Lok Sabha, which showed significant improvement in PM10 concentrations in IGP cities, barring Bihar, possibly due to recent restrictions on major pollution sources," said Dutta, senior research scholar, Bose Institute.
The study’s projections were proved correct in some states like Jharkhand, Odisha, Chhattisgarh, Madhya Pradesh, and Gujarat, dominated by thermal power plant emissions. "Our study indicated a 5-17% increase in aerosol pollution by 2023 in these states, with Madhya Pradesh showing the highest increase," said Chatterjee. This finding aligns with the data tabled before Lok Sabha by MoEFCC, which also indicated deteriorating air quality in these regions.
Interestingly, the study and the MoEFCC submissions both indicate significant air quality improvements in Rajasthan. However, the north-eastern states, known for open biomass burning showed an increase in aerosols, with Tripura identified as experiencing a substantial decline in air quality. This was attributed to long-range transport from the IGP, a finding not covered in the government report.
For the southern Indian states, the study showed a 12-24% increase in aerosol pollution by 2023, primarily due to vehicular emissions. "This projection, however, seems to contrast with the MoEFCC data, which showed substantial improvement in PM10 concentration in most southern cities," said Dutta.
Greater emphasis on PM2.5 needed
The NCAP with its ambitious target to achieve up to 40% reduction in PM10 concentrations by 2025-26, is set to be a cornerstone in the country's fight against air pollution. Under NCAP, 82 cities have been set an annual target of 3-15% reduction in PM10 levels, while 49 cities under the XVth Finance Commission air quality grant aim for a 15% yearly reduction. However, experts argue for a need to recalibrate the focus of air quality policies under NCAP on monitoring and reducing PM2.5 levels.
“PM2.5 is a fraction of PM10 and is more dangerous to health. While PM10 is constituted by both ultrafine particulate matter (PM2.5) and larger particulate matter, focusing on reducing PM2.5 will automatically reduce PM10. However, the converse may not be true,” Chatterjee said.
“The current emphasis on PM10 trends doesn't adequately capture the risk transition. This approach diverts attention towards coarse particles or dust and weakens action on the more harmful fraction of PM2.5, which predominantly comes from combustion sources,” Roychowdhury said. “Cities with a population of more than a million, having PM2.5 monitoring capabilities, should be judged based on PM2.5 trends.”
“Much of the evidence has studied the impact of fine particulate matter or PM2.5. Globally, PM2.5 has been found to be the most consistent predictor of disability and deaths due to air pollution. Therefore, PM2.5 should be the target pollutant in air quality policies, including NCAP. Attainable but ambitious interim targets should be set under NCAP,” said Dr. Harshal Salve, professor, All India Institute of Medical Sciences and co-ordinator from CAPHER India, a joint collaboration between AIIMS, New Delhi, and IIT Delhi supported by the Health Effects Institute, USA.
CAPHER India shared a recommendation on the same lines with the environment ministry earlier this year.
“PM10 and PM2.5 are correlated, and the latter is a subset of the former. Given the historic base for many areas is only by way of measurement of PM10, NCAP sets reduction targets on PM10. However, with improved measurement of PM2.5 and other criteria pollutants, ensuring all these are within statutory thresholds is important. Future reduction strategies must set limits for these too,” said Karthik Ganesan, fellow and director – research coordination at the Council on Energy, Environment, and Water (CEEW).
The MoEFCC recently sanctioned projects to evaluate the impact of air pollution on human health in 20 selected cities nationwide under the National Environmental Health Profile Study. This initiative marks a significant step in understanding and addressing the health implications of air quality in urban India as a first for India.
Comprehensive assessment needed
At present, India has a network of 1,429 ambient air quality monitoring stations which covers 511 cities/towns in 28 states and seven Union territories. However, most Tier II-III cities are equipped with only 2-3 monitoring stations, raising concerns about the comprehensive tracking of air quality improvements.
‘Improved monitoring allows Urban Local Bodies (ULBs) and regulators to understand periodic progress and adopt more effective strategies based on outcomes,” Ganesan said. He advocates for a hybrid approach to monitoring, combining reference-grade devices, satellite-based measurements, and well-calibrated low-cost monitors. "This hybrid method will provide a more robust evidence base for pollution reduction and understanding population exposure," he added.
Tripathi highlighted the importance of a diverse monitoring footprint. "This can be achieved by leveraging alternative technologies such as low-cost sensors.” He advocates for a mix of hyperlocal monitoring using such sensors, supplemented by 3-4 regulatory-based monitoring networks within each city to ensure comprehensive air quality assessment.
According to one assessment, 4,000 continuous monitoring stations (2,800 in urban areas and 1,200 in rural areas) are needed to spatially, temporally, and statistically represent ambient pollution. UrbanEmissions, an air quality research body, came up with this number based on the district-level urban and rural population data from the 2011 census.
An effective use of allocated funds plays a crucial role in combating air pollution. However, a concerning trend emerges when looking at the financial utilisation by certain states under key environmental initiatives like the National Ambient Air Monitoring Programme (NAMP) and the Fifteenth (XV) Finance Commission: In 2023, Bihar, Haryana, and Madhya Pradesh reported no utilisation of the funds allocated for air pollution control.
This startling revelation indicates a significant gap in the financial commitment required to address the air quality crisis.
Bihar, known for its dense urban population and industrial activities, faces acute air pollution challenges. The lack of fund utilisation (allocated ₹29 lakh) might contribute to the state's inability to effectively implement air quality management strategies, thus impeding progress in improving air conditions.
Similarly, Haryana, which encircles the national capital, Delhi, plays a crucial role in the region's air quality dynamics. The state's non-utilization of allocated ₹7 lakh in funds for air pollution control suggests a missed opportunity.
Madhya Pradesh's situation is equally concerning. As a state with a mix of urban industrial centres and rural expanses, effective air pollution control is crucial. The non-utilisation of funds could be linked to administrative challenges or a lack of prioritisation of air quality issues within the state's environmental agenda. Of the allocated ₹34.25 lakh, the state has not utilised a single penny towards improving air quality.
“While it is an important step forward to make the NCAP, and its funding performance based accounting for the change in air quality, it is also necessary to adopt a more effective benchmark for assessment of action,” said Roychowdhury, adding, “A lot of the current expenditure in cities is tied with road sweeping, water sprinkling and road building whereas the pollution sources including vehicles, industry, waste and solid fuels remain underfunded and without a focussed scalable strategy.”
In the XV Finance Commission's allocation for air quality grants (from 2020-21 to 2023-24), a total of ₹11,347 crore was allocated across various Indian cities, with ₹8,357.51 crores sanctioned and ₹5,450.65 crores utilised by October 2023.
A breakdown of this showed that Vijayawada and Visakhapatnam in Andhra Pradesh used only ₹38 crore and ₹21 crore out of their allocations of ₹159 crore and ₹188 crore respectively. Karnataka’s Bruhat Bangalore used ₹305.47 crores out of ₹718 crores, and Indore in Madhya Pradesh fully utilised its allocated ₹261 crores Greater Mumbai in Maharashtra utilised ₹595.04 crore of a ₹1,257 crore allocation, close to 50%.
The situation calls for a re-evaluation of strategies at both the central and state levels, emphasising the need for increased financial commitment, enhanced inter-state collaboration, and more effective utilisation of allocated funds. “The NAMP budget is actually different from the NCAP and the XV Finance Commission budgets as the latter are the ones that actually enable expenditure in addressing sources,” said Ganesan.
“The inability to expend the NAMP resources to enhance the monitoring network is a challenge. What needs to be clearly seen is how well are the resources for mitigation being spent. While faster reduction in pollution levels is desirable, the targets for 2024 and 2026 across non-attainment cities is an ambitious one and will already take significant effort to deliver and monitor for progress,” Ganesan said.
Badri Chatterjee is head, Communications (Climate & Energy) at Asar Social Impact Advisors, a research and communications organisation that works on social and environmental issues