[audio:http://wamcradio.org/EarthWise/wp-content/uploads/2012/05/EW-07-04-12-Fireworks.mp3|titles=EW 07-04-12 Fireworks]
Tonight, in honor of our nation’s independence, millions of Americans will grab a blanket or a lawn chair and watch fireworks. Pyrotechnic demonstrations have become an inseparable part of our country’s Fourth of July celebration.
Fireworks owe their brilliance to a concoction of fuels, oxidizers, propellants, binders, and coloring agents. And, as the laws of physics dictate, what goes up must come down. When fireworks are ignited, toxins and particulates rain down on soil, water, and spectators.
Perchlorate has become the preferred oxidant to fuel fireworks’ flight. It’s more stable than its predecessors, resulting in fewer explosion-related injuries. But it’s also toxic. Studies have linked perchlorate to thyroid disruption. Equally worrying— because perchlorate is water soluble, it pollutes ground and surface waters. Duds that don’t go off are another source of contamination.
The coloring agents in fireworks could also use some innovation. Currently, you can thank various elements for the rainbow you observe in the night sky. Blues are produced by copper, greens rely on barium, and reds come from strontium. These elements persist in the environment and have been linked to a variety of health concerns.
Thankfully, pyrotechnic experts are hard at work creating the next generation of perchlorate-free, low-smoke fireworks. Less smoke means less colorants need to be used.
If fireworks are too beloved a tradition to give up, encourage your town to adopt eco-friendly pyrotechnics. They cost a little more upfront, but are gentler on spectators and our shared environment.
Photo, taken on July 22, 2008, courtesy of Bayasaa via Flickr.