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Despite lockdowns, summer pollution in India remained in toxic range this year

Once again, it was noted that air pollution was not just a winter issue, but levels were above permissible limits during summer months as well 

The grim second wave of COVID-19 that struck this summer with a huge spike in deaths through March, April and May, also saw a spike in air pollution. Pollution levels this year rose despite the total and partial lockdowns, with levels in many major cities breaching the limits set by the Central Pollution Control Board (CPCB) and the World Health Organisation (WHO).

‘Need better tech to differentiate PM2.5, PM 1 composition’

Experts pointed out that pollutants are as harmful in summers as they are during winters, but India is yet to clearly identify the composition of PM2.5 and PM1. India needs to invest in technology and research, which will help differentiate and then take corrective steps, experts said. 

Dr Sundeep Salvi, former director of Chest Research Foundation, Pune, and founder of Pulmocare Research and Education (PURE) Foundation, said, “During summers, PM could be a mix of different pollutants than it is in winters. One pollutant could be more toxic than the other even at the same concentration levels.” Dr Salvi added that polluted air compromised the immune system of people making them more susceptible to respiratory illness.

‘Long-term planning, sustained action missing currently’

With pollution harming Indians throughout the year, experts called for sustained government efforts throughout the year, and across the country to reduce routine exposure. Dr Santosh Harish, Fellow at the Centre for Policy Research, New Delhi, said, “We tend to talk about air pollution only when they reach toxic levels in North India during the winters. But more than four out of five Indians are exposed to dangerous levels of pollution year-round.”

The health risks of prolonged exposure to air pollution are immense and require sustained action against it. Dr Sagnik Dey, coordinator of Centre of Excellence for Research on Clean Air (CERCA), IIT Delhi said, “Mitigation requires long-term planning, which is missing even in the current clean air action plans for non-attainment cities. It is important to identify timelines and resources and set accountability. Everyone discusses high pollution levels during the winters and focuses on emissions from crop burning, but we need to look at prioritising and reducing emissions from transport, industry and so many other sources as well.”

The pandemic restrictions in 2020 saw pollution drop to an all-time low, but the levels still remained almost three times the WHO annual safety limits of 10 ug/m3. 

Tracking National Clean Air Programme: Long way to target

Climate Trends tracked the data from India’s national clean air programme implementation and compiled an NCAP Tracker to assess if it is going to meet the target to reduce India’s particulate matter (PM) air pollution by up to 30%. The tracker’s Continuous Air Quality Monitoring Dashboard sources data from the CPCB. Based on the CAAQMS dashboard, here is a snapshot of pollution levels in the country and in Maharashtra, Uttar Pradesh, West Bengal and Delhi over the past few months and more.

On June 6, the top 10 polluted cities recorded a PM 2.5 concentration much above the WHO daily permissible limit of 25 ug/m3 (microgrammes per cubic metre) and CPCB’s 40 ug/m3. Moradabad in Uttar Pradesh and Durgapur in West Bengal were the most polluted with a PM 2.5 concentration of 79 and 73 ug/m3 over 24 hours. Data revealed that Mandi Gobindgarh in Punjab saw its PM 2.5 levels peak at 250 ug/m3 around 3am. Delhi and Patna recorded 50ug/m3  and 42 ug/m3, respectively.

Pollution hotspots in Summer 2021 (March, April and May): UP, Haryana, Rajasthan cities among the most polluted

From March to May 2021, the top 10 polluted locations all recorded a PM 2.5 concentration of more than 99 ug/m3. While the most polluted location was in Bhiwadi, Rajasthan, with a PM 2.5 concentration of 120 ug/m3, six locations on the list – Sector 62, Noida, Bawana, Mundka, CRRI Mathura Road, ITO and NSIT Dwarka, were from Delhi NCR.

In the week ending June 6, 2021, the most polluted city in the country was Sonipat, Haryana, with a PM 10 concentration of 233 ug/m3. The highest PM 2.5 concentration of 81 ug/m3 was recorded in Bhiwadi, Rajasthan. Most of the cities on the list were from Haryana, Uttar Pradesh and Rajasthan.

Most of the cities polluted since the start of 2021, too, were from Haryana, Uttar Pradesh and Rajasthan. The highest PM 10 and PM 2.5 of 281 ug/m3 and 131 ug/m3 respectively were recorded at Ghaziabad in Uttar Pradesh.   

Despite 2020 being a year of the lockdown, the PM 2.5 concentration across the non-attainment cities (NACs) of Uttar Pradesh remained above permissible limits throughout the year except in July and August. Ghaziabad recorded the highest concentration of PM 2.5 in the state for all months except July and August. Seventeen air quality monitors in UP recorded an uptime of 82%.

Until now, all 12 cities, except Hapur in April and May, have recorded a PM 2.5 concentration above the CPCB permissible limit of 40 ug/m3. The highest monthly pollution levels of 224 ug/m3 were recorded in Ghaziabad in January 2021.  

Once again dispelling the myth that air pollution is a problem of winters, the three images above show that the top 10 polluted locations in Uttar Pradesh through the summer months of March to May this year saw high pollution levels. In the summer months of March to May in 2021, all the 10 most polluted locations in UP recorded an average PM 2.5 concentration of over 70 ug/m3. The highest PM 2.5 concentration of 113 ug/m3 was recorded at Sector 62 in Noida.  

Delhi air above harmful limits throughout 2019, 2020, 2021 

Irrespective of the season, Delhi’s PM 2.5 concentration remained above permissible limits throughout 2019 and 2020 and for the five months of 2021 (except in August 2019 and 2020 and July 2020). Since 2019, the city saw its monthly average of PM 2.5 concentration spike above 200 ug/m3 in the months of January, November and December 2019 and November 2020 as well.

The PM 2.5 concentration in summer months this year was half of what it was in the winter of 2020, but it remained above permissible limits and hence harmful. Four of the top 10 polluted locations in Delhi recorded a PM 2.5 concentration of above 100 ug/m3 during the summer of 2021. This is way more than the WHO’s annual safe limits of 10 ug/m3 or CPCB’s 40 ug/m3.