Whether it’s on Canada Day or when the clock strikes 12 on New Year’s Eve, many of us share the childhood memory of seeing fireworks light up the night sky as they explode with their bright colours. According to the American Pyrotechnics Association (APA), around 18.7 million pounds of display fireworks and 385.8 million pounds of consumer fireworks were used in the US in the year 2020. That adds up to 404.5 million pounds of total consumption. That was 131.5 million more pounds than the usage in 2019 where the total consumption was 273 million pounds. From 2009 to 2013, according to the Office of the Ontario Fire Marshal, fireworks were the cause of 129 fires, leading to around $2.5 million of damage. With the number of fireworks used annually every year, concerns arise concerning the sustainability and harmful impacts of fireworks. From the harmful compounds in their colouring to the risks of forest fires, fireworks have various elements that threaten our environment. Are they truly necessary, and is the pretty night sky worth the risks and negative effects?
The Colouring of Fireworks: Air Pollution and Health Hazards
With their momentary bursts of vividly coloured light, fireworks also bring an explosion of air pollution and waste. The colouring behind pyrotechnics involves a lot of chemistry and physics. Each colour is created when a specific chemical compound is heated to just the right temperatures. The colour produced depends on the metal salt. For example, strontium salts give off red and copper salts produce blue (refer to image on left for more). The salts and explosives of the fireworks undergo combustion when combined with oxygen. When this chemical reaction occurs, smoke and gases such as carbon dioxide, carbon monoxide, nitrogen dioxide, and sulphur dioxide are released. These three gases also happen to be some of the major greenhouse gases.
Not only are they bad for the environment, but they also expose us to toxic chemicals and are harmful to one’s health. When these fireworks explode, the heavy metals do not magically disappear. Instead, their atoms stay in the air as aerosols, contaminating our air, water, and earth. According to a writer and scientist with Forbes, these metals can impose many health issues from vomiting, diarrhea, asthma, kidney disease, cardiotoxic effects, and cancers simply from inhalation or ingestion.
Image Credit: Compound Interest / CC BY-NC-ND
Loud Noise Disturbances
With the combustion also comes the loud bang. Many wild animals and even household pets have been shown to express extreme stress and trauma from the loud noises the explosions produce. During peak firework seasons, the Calgary Wildlife Rehabilitation Society (CWRS) reports a rise in spottings of wildlife in unnatural areas. Due to these sudden noises, there have been many reported cases where small mammals or birds have left behind their nests and babies. These sudden disturbances can cause the wildlife to disorientate and decrease their ability to relocate their families.
Water Pollution
In order to produce the required oxygen to fuel their combustion reactions, fireworks often contain perchlorates as oxidizers. These perchlorates pollute water and contaminate our precious rivers, lakes, and the aquatic organisms living there. Not only do perchlorates affect our waters, but if they contaminate our drinking water supplies, they can also impose the threat of a decrease in thyroid hormone production (critical for growth and development of the nervous system) upon ingesting high doses of perchlorate.
Efforts to reduce the impact
Although they are relatively small steps, scientists are making efforts to develop more environmentally-friendly alternatives with compositions that reduce the need for perchlorates or utilize compressed air to reduce the release of harmful products. Cities around the world such as Beijing and Collecchio have implemented policies such as outlawing the usage of fireworks entirely or utilizing silent fireworks to reduce their impacts. In Canada, Banff has also switched to a quieter pyrotechnic display often used in rock concerts in order to not terrify the local wildlife. Vancouver, another city in Canada, arranged their firework ban, which came into effect on the first of November 2020. Although these are small steps in order to solve our climate crisis, it is important to take these necessary strides to make advancements in our traditions and technologies for a safer and greener future.