New Delhi: A ban on the use of fireworks in various forms has been implemented every year during Diwali since 2017 to check aggravation of air pollution. On Thursday, Delhi govt told the Supreme Court that it wanted to ban firecrackers permanently in Delhi. Though the pyrotechnics significantly impact the air quality in the winter months, their impact is less in the summer when pollutant dispersion is quicker.
While the court has sought the views of the neighbouring states on Delhi’s proposal to ban fireworks, experts pointed out that pollution levels can be significantly reduced even otherwise by acting on other sources of pollution, such as vehicular emissions, industries, construction and demolition, stubble burning and thermal power plants, which release more pollutants than fireworks.
Firecrackers release sulfur dioxide, carbon dioxide, carbon monoxide, particulate matter and toxic heavy metals like cadmium and lead. They contain other metals like copper, manganese, zinc, sodium, magnesium, and potassium in nitrate and nitrite forms. Monitoring of the air in Delhi during Diwali has noted a rise in pollution. Several studies in other countries have similarly established that firework emissions can cause air quality to deteriorate. In Beijing, a study of air pollution caused by a firework display during the Lantern Day Festival in 2006 reported more sulfur dioxide, nitrogen dioxide and PM10 pollutants in the air than the previous day.
Dipankar Saha, former head of the air laboratory at Central Pollution Control Board, said, “Firecrackers need to be restricted as they suddenly increase emissions in the air, especially when it is at a standstill and there is little dilution and dispersion. Fireworks could be permitted under favourable meteorological conditions. We saw minimal impact of fireworks on pollution last Diwali because of increased wind speed that day.”
However, the problem with fireworks is not just that they release pollutants but also their dynamics. As Mukesh Khare, professor emeritus, IIT-Delhi explained, the firecrackers are a low-level emission source as they burst at surface level. “The pollutants go a small distance into the air and fall down,” Khare said. “In the colder months, especially in north India, the wind velocity and temperatures are low and humidity is a bit higher. After a cracker is ignited, the explosive pollutants are emitted into the atmosphere, but as the surrounding temperature is low and winds are not fast, the pollutants don’t travel far, either vertically or horizontally. Only people close to the burn site are exposed to the emissions.”
Khare, however, added that large-scale burning of fireworks means the pollutants are at boundary layer height and so unable to disperse due to meteorological conditions. “The lower atmosphere gets affected by pollution,” he pointed out. “The contaminated air is inhaled into the lungs of people.” In summer, dispersion diminishes the adverse effect on air quality.
Though there is no apportionment study detailing firework’s contribution in Delhi’s air quality, experts said there are other more insidious pollution sources. Sunil Dahiya, founder and lead analyst, Envirocatalysts, described a permanent ban on fireworks as a “good symbolic step” that will underline how anything that burns causes pollution. “Delhi-NCR has other consistent pollution sources, which emit higher emissions throughout the year than firecrackers do,” said Dahiya, who, therefore, wanted authorities to act against vehicular emissions, industrial, power plants, waste burning and construction dust with the same intent.
There is also the fact that chemical debris from fireworks contaminates the soil and groundwater and is harmful to animals and birds. A study done by an international team of scientists who tracked Arctic migratory geese in Germany, Denmark and the Netherlands spanning the New Year period, typically when crackers are burst, found the birds deserted their sleeping sites on hearing firework noise and never returned.
Chandra Bhushan, CEO, International Forum for Environment, Sustainability, and Technology, agreed with the destructive repercussions of fireworks, noting additionally that they cause fires that damage homes and properties.
So, while firework emissions appear hazardous, the chemical compounds the crackers contain also damage the soil and groundwater. However, banning fireworks and hoping it proves the solution to the city’s choking air may be misconceived because there are pollutant sources that are more detrimental and about which no strong actions are proposed.
