Oohs, Ahhs, and Toxic Aftermath of Fireworks

Fireworks look amazing lighting up the night sky, but scientists have discovered they leave behind pollution that can linger long after the show is over. Three new studies looked at what really happens after the fireworks fade.

Leftover Firework “Trash” Pollutes Water

After fireworks explode, burned pieces and leftover chemicals fall back to the ground. Rain can wash this debris into nearby rivers and lakes, where it releases metals and other chemicals into the water. It can also change how other pollutants behave. Scientists worry this could disrupt the tiny microbes and other organisms that help keep these ecosystems healthy, especially in places where fireworks are used year after year.

Fireworks Add to Air Pollution at Big Events

---

The Silent Victims of Fireworks

For many Americans, fireworks are a cherished holiday tradition. But for wildlife, they can be frightening—and sometimes deadly. We often hear about terrified cats and dogs, but birds, bats, and other wild animals can suffer too.

One heartbreaking example happened on New Year’s Day in Bulgaria. A hiker found hundreds of dead birds scattered on a snowy trail. Scientists believe a fireworks show the night before scared the birds into taking off in a panic, causing them to crash into trees and each other.

Why Fireworks Freak Animals Out

Fireworks can be terrifying for wildlife. The loud explosions often wake birds while they’re sleeping or resting, causing them to panic and crash into trees, buildings, or windows as they try to escape. Animals with especially sensitive hearing, like owls, can be even more affected by the noise. Deer and rabbits often bolt when they hear what sounds like danger, sometimes running into fences or other obstacles in the dark. In some cases, frightened animal parents even abandon their babies. For animals like porcupines, which usually have only one or two babies each year, losing a litter can make it much harder for their populations to recover.

Studies found geese show signs of stress during fireworks, including including faster heartbeats and higher body temperatures. In California, bats stopped hunting for food during a 30-minute fireworks show, though they went back to normal fairly quickly. Scientists worry that repeated stress from fireworks could add up over time, even if each event only causes short-term problems.

Is There a Solution?

Some cities, including Salt Lake City, Utah; Boulder, Colorado; and Morro Bay, California, have started using drone light shows instead of fireworks. They’re much quieter and don’t create smoke or start wildfires. However, they do make a faint high-pitched sound that may still bother some animals, such as seagulls. (Apparently, some dogs aren’t fans either.)

While experts don’t think fireworks are going away anytime soon, they recommend keeping fireworks at least a mile away from forests, parks, wetlands, and nesting areas—especially during spring and summer, when many animals are raising their young.

Want to learn more about how people are changing our planet? Explore more science stories here.