One of the busiest times for summer in the Lake Region centers around the 4th of July holiday. Along with parades, water sports, and cookouts, the highlight for many residents and visitors is seeing fireworks. Some local towns and many private citizens put on fireworks displays, often launched out over a lake. What could be a more quintessential summer activity than a dazzling aerial display enjoyed from a boat or the lake shore, right?
Well, unfortunately, fireworks come with a downside: they have a range of negative environmental impacts. First, the noise and light from each explosion scare wildlife like loons. Second, the smoke generated by the combustion adds particulates to the atmosphere, in some cases exceeding air quality standards. Third, residue from the explosions and misfires creates litter and has the potential to cause fires. Last, many of the chemicals that give each shell its color and design are toxic and can impact water quality once the residue settles.
Once such chemical is perchlorate. Perchlorate, a single chlorine atom bonded to four oxygen atoms, is used as an oxidizer in fireworks and rocket propellants. When humans are exposed to high enough concentrations, perchlorate inhibits iodide uptake by the thyroid, which impacts thyroid hormone production. California and Massachusetts regulate this chemical in drinking water, but the EPA has yet to formalize a national regulation. As part of mandated regulatory development, the EPA has funded research into perchlorate occurrence in ambient waters following fireworks usage.
This past summer, LEA took part in just such an EPA-funded project awarded to Texas Tech University and collaborators. We collected and filtered lake water samples before, the day after, and a week after fireworks shows occurred on Long Lake and Trickey Pond. We shipped the samples off to the principal investigators for the perchlorate analysis. We hope to get the results for our two lakes and others in the study soon, and we will report back on them in a future issue.
As noted above, perchlorate is not the only issue with fireworks. Fireworks used to contain phosphorus compounds, which could contribute to algae growth. Fortunately, current products have only trace amounts. Litter is another concern, and while we were collecting samples, we came upon significant fireworks debris floating on Long Lake. Some appeared to be from consumer fireworks, available for sale in Maine since 2011. So next July, if you or people you know plan to use fireworks, please avoid shooting them over water and clean up the debris afterward. The lakes and all their inhabitants will thank you for that.
-Ben Peierls, LEA Research Director
