More colour, more danger

Here’s why, as explained by B Nagappa, a scientist from the Karnataka State Pollution Control Board (KSPCB): Light-emitting crackers have heavy toxic metals which are more harmful to environment than smoke-emitting crackers.

“Crackers that emit bright light in the atmosphere do so mainly due to the presence of heavy metals such as copper, cadmium, nickel, barium, beryllium, sodium and potassium. After a cracker bursts, these metals in the form of dust fall down and easily get into the atmosphere. These metal oxides affect animals, birds, trees and plants, too, on a large-scale,” he explains.

Regular crackers, mainly sparklers and flowerpots, contain sodium, potassium and lithium and emit oxides after combustion. Sodium emits golden yellow and potassium brick red colours. On the other hand, the coloured high-end rockets contain mainly nickel which emits shades of green; copper-barium-beryllium and aluminium emit shades of blue when burnt in various intensities.

Metal oxides are emitted after combustion at high temperature. In this case, normally carbon dioxide, carbon monoxide, sulphur dioxide and oxides of nitrogen are let out into the atmosphere. The sound generated by crackers is mainly due to the opening of a firework’s wrapping, says Nagappa.

Rains beneficial
The environment benefits most if it rains after crackers are burst. Bangalore was lucky that way in 2010. But, as Nagappa put it, this year, due to a dry spell, the air pollution level may increase. Fine dust particles of oxides of heavy metals, which percolate the atmosphere, can easily enter our lungs causing long-term adverse reactions. “Nickel and cadmium are very dangerous among the chemicals used in fireworks. If aluminium particles measuring more than 0.2 ppm falls on water bodies, it contaminates the water,” he warned.

The Petroleum and Explosives Safety Organisation (PESO) specifies that the manufacture, sale and use of firecrackers generating noise level exceeding 125 decibels (dB) (AI) or 145 dB (C ) pk at four metres distance from the point of bursting, should be prohibited. For an individual firecracker constituting the series (joined firecrackers), the specified limit should be reduced by 5 log 10(N) dB where N is the number of crackers joined together.

PESO has come out with a chemical formula for four types of commonly used sound-producing firecrackers, namely atom bomb, Chinese crackers, maroons and garland crackers.

It clearly specifies the proportion / composition as well as the maximum permissible weight of every chemical used in the manufacture of crackers. PESO bans the use of heavy metals in crackers and has permitted to use only aluminium powder, sulphur, potassium nitrate and barium nitrate in all the four categories of fireworks.

Almost all crackers that find their way to Bangalore are manufactured in Sivakasi in Tamil Nadu. These fireworks are supplied to the City through dealers. It is the responsibility of the police to keep a tab on dealers who buy crackers and sell them at different locations in the City and the State.

A Supreme Court directive requires every manufacturer to mention the details of chemical contents of firecrackers. The Noise and Pollution (Regulation and Control) Rules, 2000, was subsequently amended many times with the latest rules framed in January 2010 under the Environment (Protection) Act, 1986. The rules mandate that the noise level of the cracker should not be more than 125 decibels and its weight not more than 20 gram.

But despite the rules, in most cases, the buyer does not check the details and ends up buying fake or dangerous crackers that are not manufactured according to the PESO requirements. One of the most repeated violations by a manufacturer is failing to write the chemical composition of the crackers on the covers of fireworks. In most cases, this is not printed at all.