For 364 days of the year, we pound Delhi’s air with pollutants like sulphur dioxide, nitrogen dioxide, and suspended particulate matter (PM) like PM10 and PM2.5 .
For one day, we want that there should be no crackers and we are sanctimonious about a ‘Green Diwali’.
Are crackers really the cause of pollution? Or is it vehicular pollution fuelled by a gift culture around the festive season that leads to a spike in noxious gases that hang as a deathly cloud over Delhi?
Data shows that an alarmingly high increase in pollution levels does take place due to the bursting of crackers. According to the System of Air Quality and Weather Forecasting and Research of the Union ministry of earth sciences, the levels of PM10 and PM2.5 in Delhi for this year post Diwali were recorded at severe levels of 785 micrograms per cubic metre and 491 micrograms per cubic metre, respectively.
The safe limit of PM10 is 100 micrograms per cubic metre and PM2.5 is 60 micrograms per cubic metre, which means that the national capital witnessed nearly eight times the level of PM10 and PM2.5.
But what this stand-alone data does not tell us is that, year round,
Delhi’s pollution levels are consistently above the safe limits. Further, it is the source of the pollution and the one we choose to react to that reflects our own mindset. And a ban on crackers will not ensure that Delhi’s air remains free of pollutants.
A study by the Indian Institute of Technology Kanpur, (the first of its kind to comprehensively study Delhi’s air pollution levels, which came out in January this year) revealed data that was as alarming for the summer months—the annual concentration of PM10 was 500 micrograms per cubic metre against the acceptable level of 100 micrograms per cubic metre and PM2.5 was at 300 micrograms per cubic metre against 60 micrograms per cubic metre as permissible limit in the summer months in the capital. In general, while winter limits are higher, the summer limits are also high, and yet the media and the public focus on pollution only in the winter.
The IIT Kanpur report further states that “in a broad sense, air is more toxic in winter than in summer as it contains much larger contribution of combustion products in winter than in summer months”. But that does not discount the fact that Delhi’s air is polluted even in summer months.
The sources of pollution also differed sharply, showing that vehicles are a much bigger contributor to air pollution in the winter than in the summer. The same study listed sources of pollution we seldom acknowledge. For example, there are approximately 9,000 hotels/restaurants in the city of New Delhi, which use coal (mostly in tandoors). The PM emission in the form of fly ash from this source is large and contributes to air pollution. That’s why the report has strongly recommended that “all restaurants of sitting capacity more than 10 should not use coal and shift to electric or gas-based appliances”.
Stubble burning from the farms in Haryana and Punjab, along with the trucks entering Delhi, are some of the other sources of pollution, but the report emphasizes that their contribution may differ according to the season.
But as Rohini Pande from the Harvard Kennedy School, while commenting on the IIT Kanpur study, argues, “For the quality of air to improve, the quality of information must first rise. With even a rough idea of source apportionment, the government can take actions like shutting down dirty power plants and pushing neighbouring states to better regulate crop burning. Once the low-hanging fruit is picked, policymakers will need increasingly detailed information on location, source, and type of air pollution to design a smart policy response.”
That’s why knowing what causes Delhi’s air to be polluted at what time of the year is imperative. After Diwali, asking for a ban on crackers may seem like a knee-jerk reaction that will not address the complexity of the problem. Moreover, it is obvious that the middle class does not want to address the real issues such as rampant construction, intensive use of cars during the festive season or any intervention that will inconvenience our own lifestyle.
Our focus needs to shift from a cracker-less Diwali to a pollution-free city the whole year round. We need to push our politicians for better legislation for public transport, better implementation of laws around construction sites and implementation of highest standards of emission control from vehicles.
The time is ripe for change. But for that, we need to be rid of our selective amnesia about pollution. This is not an issue we can tackle only around Diwali. It needs year-round intervention.
Bahar Dutt is a conservation biologist and author of Green Wars: Dispatches from a Vanishing World.