Who doesn’t love fireworks? (Aside from our dog, our kids when they were little, and apparently birds – although no surprise there really). It’s also likely that those who are responsible for ensuring water quality have mixed feelings when the sparks start flying. I don’t want to be the kill-joy, but when Island Press asked if there are any enviro-downers for fireworks, a single word popped into my mind: perchlorate.

Like other things in need of a combustive blast (think: matches, military explosives and rocket fuel), fireworks rely on a chemical called perchlorate, now known to be a powerful thyroid toxicant. In some locales (including explosives factories, military grounds where there is prolonged or repeated blasting, and yes – favored sites for firework displays) perchlorate can be found in groundwater and surface waters where it tends to persist in potentially toxic concentrations.

But there is hope! Fireworks, like other favored chemical products, may someday soon become at least a little less polluting. (Though I doubt this would be of any consolation to all those dogs cowering under the beds – it is hard to imagine the blast without the boom.) If you are curious about the chemicals that light up our Fourth, check out Andy Brunning’s excellent infographic about the Chemistry of Firework Pollution below or at Compoundchem.com. Brunning’s graphics provide a glimpse of the chemistry behind everything from Sunglasses to Neonicotinoids, Mummification, Recycling Rates of Cell Phone Metals even The Smell of Garbage – enjoy!