Spectacle and environmental hazard: fireworks are falling out of fashion

While fireworks have been an essential attribute of New Year’s celebrations, scientists warn their effects on the environment and the health of people and animals may outweigh the benefits.

Many historians believe that the first fireworks or natural firecrackers were fired in the ancient city of Liuyang in China in the second century BC. They were bamboo sticks that, when thrown into a fire, exploded with a bang. The Chinese believed that these natural firecrackers scared away evil spirits.

According to legend, between 600 and 900 AD, a Chinese alchemist mixed potassium nitrate, sulphur and charcoal to make a black, shimmering powder – the first gunpowder. It was poured into convex bamboo sticks (and later into rigid paper tubes) to make the first man-made fireworks.

Today, more than 12 centuries later, gunpowder, together with additional chemical compounds, makes up the pyrotechnic mixture for fireworks. It is deposited into the inert part of the firework made of paper, clay, cardboard, or wood.

“The gunpowder in them [fireworks] gives a vigorous burn, a shot, and the different chemical compounds added to the mix colour the flame in different shades,” says Dominykas Juknelevičius, a researcher at the Organic Chemistry Division of the Centre for Physical and Technological Sciences (FTMC).

While fireworks are an impressive spectacle, environmentalists have been worried for some time about the chemical footprint they leave behind.

According to the Environmental Protection Agency, when fireworks are fired in large numbers, such as on New Year’s Eve, air quality monitoring stations record increased concentrations of particulate matter (PM10, PM2.5), sulphur dioxide, nitrogen oxides and carbon monoxide. These pollutants increase several times during the first hour of January 1.

“On New Year’s Eve, when fireworks and other pyrotechnics are fired, airborne concentrations of particulate matter (PM10) are measured in cities at levels several to 10 times higher,” says Vilma Bimbaitė, head of the Environmental Protection Agency’s Air Quality Assessment Unit,

“For comparison, in Vilnius, the hourly concentration of PM10 in Savanorių Avenue before the 2023 celebrations, when fireworks were not yet fired, was 19 µg/m3, but after the fireworks were fired, it increased 3-fold to 61 µg/m3,” she adds.

The International Agency for Research on Cancer (IARC) classifies particulate matter as a Group 1 carcinogen.

According to Matas Budriūnas, a specialist at the Public Health Monitoring and Strategic Planning Unit of the Public Health Bureau of Vilnius City Municipality, even short-term exposure to carbon dioxide, carbon monoxide, nitrogen and sulphur dioxides, and particulate matter can cause short-term health problems.

“It is important to note that we are exposed to so many different harmful substances at the same time, so the effects can be much more significant. This can lead to coughing or even shortness of breath, impaired overall lung function and an increased risk of cardiac arrhythmia,” he says.

In addition, Budriūnas points out that the increased air pollution caused by fireworks is particularly dangerous for people suffering from chronic respiratory and heart diseases, as well as for the elderly and children due to their weaker immunity.

Are all fireworks equally bad?

However, chemists Rimantas Vaitkus, Dominykas Juknelevičius, and Rytis Kubilius, in their report on the environmental impact of fireworks, point out that the concentration of polluting chemicals in the air depends on the altitude at which fireworks explode.

“Professional fireworks are fired at a much higher altitude, which results in a much better dispersion of particulates,” they say.

By contrast, the hike in pollution recorded by research stations usually results from small-scale but numerous fireworks and firecrackers fired by ordinary people in their backyards and on the streets.

Therefore, to reduce the pollution and health impacts on New Year’s Eve, it would be better to enjoy professional fireworks and forego firing them yourself, says the report.

Environmental impact

Experts disagree on the long-term environmental impact of fireworks emissions. According to Bimbaitė of the Environmental Protection Agency, when pyrotechnics explode, the pollutants emitted into the air do not disappear but are dispersed in the atmosphere and subsequently enter surface waters and soil. Their effects are therefore both short-term and long-term.

In their report, Vaitkus, Juknelevičius, and Kubilius quote a study suggesting that, although fireworks fired in Florida (US) over 10 years have produced significant amounts of strontium, barium, and antimony compounds, they have not been detected in the food chain of animals in the area.

The chemists also note that environmental pollution caused by fireworks is mostly localised.

“In Austria, snow before and after the New Year fireworks show was studied. It was found that the pollution was only present on the surface of the smoke-stained snow in the immediate vicinity of the firing site. [...] No signs of contamination were recorded on the nearest mountain peaks.”

The emitted particles tend to rapidly absorb moisture and do not travel far, they say in the report.

They also point out that the most serious soil contamination occurs when pyrotechnic mixtures do not explode and fall to the ground.

Impact on pets

The sound level of fireworks is often between that of a gunshot and that of a rising jet engine. The loudest firework explosions can reach sound levels of 130-150 dB at close range. This, together with the repetitive flashes of light and the specific smell of pyrotechnics, can be extremely stressful for domestic animals.

“Firework explosions produce sound waves that are loud and sudden. Dogs and cats hear a wider range of sounds, so a loud and unexpected noise can frighten them. In addition, dogs and cats have sensitive eyesight and may react negatively to the flashes of light and flashes of colour that are characteristic of fireworks. They are also affected by the unpleasant smell of the explosion,” says Dalia Juodžentė, associate professor at the Lithuanian University of Health Sciences (LSMU) and veterinary surgeon.

How an animal responds to different sounds depends on a variety of factors, including species, heredity, environmental conditions and individual characteristics, she notes. For example, animals that are very young, under-socialised or that have experienced traumatic events in the past will usually react less well to the noise of fireworks.

Juodžentė recommends that such pets should not be left alone in the house on New Year’s Eve. If there is no other option, the animal should be put in a room with sound insulation and given toys or treats to occupy itself with.

Even if a pet is not very sensitive to sounds, Juodžentė suggests engaging in as much physical or mental activity as possible during the day before New Year’s celebrations so that by the evening the pet feels more tired, more relaxed, and less likely to react to extraneous noises.