Mumbai: After Delhi’s winter air pollution started making it to international headlines last decade complete with photographs of buildings engulfed by smog, and the ensuing health concerns, public outcry and a political slugfest, the environment ministry constituted a National Clean Air Programme (NCAP) in 2019. The programme’s objective was to reduce air pollution levels across the country with a target of 20-30% reduction of particulate matter concentration by 2024. The target was later revised to 40% reduction by 2026. A Graded Response Action Plan (GRAP) was brought in specifically for the National Capital Region as well. The government has released around Rs 9,650 crore to the 131 cities identified under NCAP between 2019 and 2024. Of this, Rs 6,316 crore has been utilised.

Despite the funds poured in, air pollution still makes headlines--not just Delhi’s but that of north India and other regions. Experts believe NCAP still has a long way to go.

For example, in 2023, Delhi recorded the highest PM 2.5 levels of 102 μg/m³, an increase of 2.5% compared to 2022. Patna exhibited the highest PM 10 levels in 2023 at 212.1 μg/m³, up from 191.6 μg/m³ in 2022, according to research done by Climate Trends and Respirer Living Sciences. As observed over the years, 18 of the top 20 cities with highest PM 2.5 concentration and 14 of top 20 cities with highest PM 10 concentration are located in the Indo-Gangetic Plain, underscoring the region's vulnerability to heightened particulate matter concentrations.

The concentrations in the top 10 polluted cities of India in 2023 were three to five times higher than Indian air quality standards and 13-20 times the World Health Organization standard, per a report by Centre for Research on Energy and Clean Air (CREA).

As India completes five years of NCAP, IndiaSpend speaks to Abhijit Chatterjee, a researcher on air quality and air pollution with Bose Institute, Kolkata, which is funded by the Indian government’s Department of Science and Technology on the progress so far. Chatterjee is also an adviser on NCAP.

Edited excerpts:

NCAP completed five years this year. Poor air quality is becoming a cause for concern not just in 131 non-attainment cities, but across India now. Do you see that reflected in the efforts of the government?

It is true that before the launch of the National Clean Air Programme, there was no such separate initiative for clean air. But still, I would say that air quality has not become one of India’s top priorities. Even people do not think that these are major issues, they do not recognise that this is a problem. Unless the common people of India outrage or seriously demand clean air, political leaders will not act either. If there is a mass revolution for good air quality, political leaders will take it into account while seeking votes. Scientists and policymakers are ready with their policies on how to mitigate air pollution. The only thing that we need is good political will.

There is an underutilisation of funds allotted for taking measures to curb air pollution. Does this also further reflect the lack of willpower or are there any other reasons?

Under NCAP, the implementing body is the urban local body. What I have found while working with the Kolkata municipal corporation and some other municipalities in West Bengal is that there is no additional manpower that was created, recruited or designated exclusively for NCAP. So the entire programme of framing the policies, writing the reports, etc. has become a kind of a burden for the urban local body. Even if some urban local bodies have the willpower to do something good, they haven't got additional manpower for NCAP.

India has increased its Continuous Ambient Air Quality Monitoring Stations (CAAQMS) but manual monitoring stations are lagging behind. Does that hinder air quality monitoring?

In terms of importance, CAAQMS are more significant because they will give you real-time data. If you want to get the concentrations of some particular pollutant at a particular time of the day, you can look at CAAQMS because it gives you data at intervals of five-minute, half hour also; plus this is high-resolution data. Whereas at manual stations, they collect the pollutants over a 12-hour, 24-hour, or 8-hour average sampling interval. The advantage of manual sampling is that you can collect those samples, and they can be analysed for their components. You can go for their clinical analysis and find out what are the most toxic elements present in those PM 2.5, PM 10 particles that CAAQMS cannot give you. I think in the current scenario, the approach to have more CAAQMS is better.

Is monitoring air pollution in rural areas still a pipe dream? According to a CREA report, India was supposed to have 100 monitoring stations in rural areas by 2024 but only has 26 so far.

I have raised this before several committees because rural areas are as polluted as the urban environment in the current scenario. Reasons could be because of the use of low grade coal, frequent use of diesel, biomass burning for fuel in households because of the high price and high refilling cost of LPG… The underprivileged cannot afford LPG and are getting back to the conventional dung cakes, biomass or solid fuel burning for domestic use. We need to take the rural environment into account for mitigation of air pollution from our country in the true sense.

In fact, the approach should not be targeted at cities or villages but at airsheds. An airshed means an area or region where the major sources of air pollution are common. For example, the entire Indo Gangetic Plain, starting from Punjab, Haryana, Delhi, UP, Bihar, Jharkhand and West Bengal. Here, the major source in the current scenario is biomass burning or solid fuel burning which needs to be mitigated. An airshed includes rural, semi-urban, urban, metro cities, whatever falls under it. So, you shouldn't ignore the rural environment at all.

If our approach is an airshed which includes villages, how much do we need to expand our monitoring network? Is it possible to set up a monitoring network at a village level?

That's the reason why we should go for remote-sensing data and satellite-based data. You have to start coupling ground-based observation with satellite-based observation. It is really not possible to install samplers in every corner of the country, rural or urban. That is why you have to take the help of satellite-based observation and remote sensing data, coupled with ground-based observation.

What is the status of India's remote sensing and satellite efficiency?

Satellite data is available. You need some manpower to retrieve the data, then you have to gather it and analyse it, that's all.

You are saying that the satellites, equipment and software are available, it is just that we do not have a policy to analyse that yet and we have not allocated manpower to that yet?

Well, there are institutions, universities and other organisations that are using satellite data to study air pollution over some specific regions. But that is kind of a closed-door research or for the specific use of a particular institute's mandate or their curriculum. All this data should be gathered on a common platform and that platform should have ground-based data available from NCAP as well. That way, a full and detailed analysis from various perspectives, efforts becomes available.

Despite NCAP's goal for air pollution forecasting systems in non-attainment cities by 2022, only Delhi has a functional system by December 2023. Is air pollution forecasting being done actively globally? What are some challenges for India?

In the Indian context, air pollution forecasting is not being focused so much like the other parts of the world. For proper forecasting, you need to have good high-temporal or time resolution data. Unless you have the data for the last five or six years for a given place, you cannot go for good forecasting or nowcasting. Unless you build a good database of high-resolution data, you cannot go for forecasting.

Source apportionment studies are important for identifying sources of pollution and the extent of their contribution. The CREA report showed that only 44 cities have done these studies until December 2023. Why is it so difficult to do this study? Is it a lack of guidance, willpower or funds?

No, there is no lack of guidance. The institutions that have taken responsibility for source apportionment studies are well guided. It requires some specific models called source receptor models. It is also a tedious job that involves chemical analysis of a filter paper manually, has to be done extremely meticulously. One small mistake or one wrong step can lead to different results. Good expertise and knowledge of chemistry is extremely important for conducting these studies. That is the only challenge.

Many factors contribute to air pollution, be it industrial emissions, thermal power plant emissions, vehicular emissions, construction dust, etc. Do you see the government handling air pollution as a multi-department, multi-sectoral problem?

Well, that is an issue for policymakers. I think for immediate reduction in air pollution, especially in the cities, local sources are more important. For example, construction dust or demolition activities, vehicular emissions, burning of solid fuel, biomass are the major sources that need to be cut down at the source immediately.

There is a definite need to penalise sectors, industries and individuals who repeatedly contribute to air pollution of a region. First, they can be given incentives to adhere to emission guidelines, especially smaller industries. For example, most regions of India have a plethora of brick kilns located in different places, either on the outskirts of the city, or in the rural environment. Most of them are illegal or not registered properly. In source apportionment results from non-attainment cities, the contribution of brick kilns is being underestimated.

East and northeast India is also showing very high levels of air pollution. A city called Byrnihat in Meghalaya was the most polluted city last year as per the CREA report.

Northeastern states experience the pollutants coming from the Indo-Gangetic Plain as well as have their own emissions, for instance, from wildfires. Wildfires are a major cause of air pollution there. Plus there is a significant change in their land use, land cover. High level of deforestation is also happening there.

Is the progress of NCAP satisfactory so far or does it require a different approach?

NCAP’s vision is to reduce or mitigate air pollution and without taking the rural environment into account, we cannot achieve that. In the Indian context, for the rural environment, biomass burning or domestic emissions should be prioritised and worked upon seriously. This is the only thing left to modify in NCAP. Around 60% voters in India live in a rural environment after all.

(Anushka Kogta, intern with IndiaSpend, contributed to this story)

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