Japan’s Fireworks Breakthrough Sparks interest

Spectacular fireworks are beloved around the world, but a polymer scientist and fireworks company in Japan — home to a centuries-old firework festival tradition — have developed a new way to light up the skies with dazzling bursts of color: more environmentally-friendly fireworks.

The Straits Times reports that a Japanese team including Takahiko Nakaoki, a polymer science professor at Ryukoku University, and Kakinoki Fireworks has developed an innovative approach aimed at reducing the environmental impact of fireworks. Their eco-friendly fireworks are designed to eliminate the debris typically left behind after a display, generating excitement among environmentally-conscious fireworks enthusiasts. 

These Fireworks Boast a Smaller Environmental Footprint
Fireworks — the carefully engineered use of fire, explosives, and chemical compounds to create visual effects — are a beloved feature of Japanese festivals, or hanabi taikai. Displays are particularly popular along rivers and other bodies of water, where the reflections can amplify the spectacle.

Fireworks also have a deep cultural history in Japan. According to Good Luck Trip, early displays were associated with mourning the dead, and offering comfort to their spirits. Japan’s first recorded public fireworks display took place in 1733 during the Edo period, along the Sumida River in what is now Tokyo, as part of a festival honoring the water god. 

Over time, fireworks evolved from solemn tradition into a major form of summer entertainment, as  Kogugakuin University elaborates. As audiences grew, hanabi displays — often associated with so-called “river-opening” festivals — became a defining feature of Japan’s hot and humid summers, drawing crowds to riversides and waterfronts to enjoy the illuminated skies.

A More Sustainable Shell
Sustainability publication, Impactful Ninja, reports that a Japanese professor has teamed up with a  fireworks company to develop what may be among the world’s first water-soluble fireworks shells. Designed to dissolve naturally after a display, the shells could significantly reduce the physical debris left behind by conventional fireworks, including spent casings that can accumulate in parks, streets, and waterways.

The innovation addresses one of the most visible environmental drawbacks of traditional fireworks: the litter generated when their paper, plastic, and other shell components fall back to the ground or into nearby bodies of water. Reducing this debris could also lessen the cleanup needed after large-scale displays.

However biodegradable or water-soluble shells do not eliminate every environmental impact associated with fireworks. As Earth notes, fireworks can still produce carbon emissions, airborne pollutants, and significant noise during combustion.

Life Positive reports that residues containing metals and other chemical compounds can settle into soil or enter lakes, rivers, and groundwater. In dry environments, the heat and sparks generated by fireworks can increase the risk of wildfires.

Understanding ‘Green Fireworks’
Japan’s prominent daily, The Mainichi, explains the construction of traditional fireworks, which consist of layered gunpowder encased in an outer shell. When ignited, this shell bursts open, scattering debris. Typically, the remnants from conventional fireworks  — often made from Kraft paper  — can take up to six months to decompose. Innovative new biodegradable shells are designed to break down in just one day.

Hiroyuki Kakinoki, head of the Kakinoki Fireworks Industry Company, shared his commitment with  The Mainichi to “accelerate the decomposition speed and reduce the environmental burden.” He plans to produce 20,000 fireworks this year, with a goal of making half of them eco-friendly.

The Straits Times reports that Kakinoki’s company has been researching and developing environmentally-friendly fireworks for around 25 years. It previously attempted to create shells using an alternative biodegradable resin, but abandoned the idea due to issues such as the creation of microplastics. However, since meeting scientist Nakaoki in 2018, the two have collaborated diligently on innovative solutions that have led to these new, eco-conscious firework shells.

These new casings are made from a water-soluble resin already used in agriculture to coat seeds and soil enhancers, thus avoiding the need for additional regulatory approval.  When exposed to moisture, the shells soften, resembling heated caramel.

The biodegradable resin is safe for consumption by living organisms, and poses no harmful effects on the environment. It dissolves harmlessly upon contact with moisture, completely breaking down within a day in flowing water environments like rivers. This is crucial in Japan,  where many fireworks displays take place over large bodies of water, as pointed out by Impactful Ninja.

Additionally, these eco-friendly fireworks utilize a design that reduces paper packaging by approximately half compared to traditional options. While Kraft paper is still used to protect against moisture, the new fireworks only require a single A3 sheet, rather than the customary two used in aerial fireworks.