Fireworks – lovely to look at but leaving a residue that should worry you? So it appears, though change may be on the horizon.
A number of concerns have been raised about the lingering effects of the popular pyrotechnic displays, from perchlorate contaminants in water to heavy metal and a sulfur-coal compound dust that pollutes air, land and water.
Perchlorates are a significant concern. They are used as oxidizers to make the metals burn, which add color to the display. The perchlorate salts disrupts thyroid function by inhibiting the uptake of iodine. While they do occur naturally, the U.S. Environmental Protection Agency began the process of determining levels at which it must be regulated in February 2011 after determining that excessive perchlorates were a significant health risk.
The EPA’s Richard Wilkin and colleagues conducted research on the use of pyrotechnic devices over bodies of water, establishing fireworks displays as a source of perchlorate contamination by analyzing water in an Oklahoma lake before and after fireworks displays in 2004, 2005 and 2006.
Within 14 hours after the fireworks, perchlorate levels rose 24 to 1,028 times above background levels. Levels peaked about 24 hours after the display, but could take up to as much as 80 days to return to their pre-fireworks levels.
What is not yet understood nor yet receiving attention from the EPA are the heavy metal contaminants, some of which may actually exacerbate a known effect of the smoke and dust created: lung irritation.
It is currently recommended that those sensitive to particle pollution avoid exposure by staying upwind of fireworks, according to Francisco Arcuate with the EPA’s District 5 Office in Chicago. The list of those who should avoid exposure includes not only those with lung and heart diseases, it includes the very young and elderly as well. This warning is based solely upon known effects from particulate pollution.
The immediate effect of inhaling these heavy metals is likely slim for those not listed in the EPA’s warning. However, the effect of cumulative exposure has not been studied. Nor has the accumulation of heavy metals in the areas where fireworks are set off. Most municipalities use the same site year after year.
Not all the metals used in fireworks are of great concern, but some do possess the potential to do harm when exposure reaches higher levels. To name a few:
• Red equals lithium in the world of pyrotechnics. Highly corrosive, Lithium compounds tend to irritate the lungs and with exposure to moisture produce hydroxide, another corrosive element. Both cause damage to the tissues. Ingested, it acts on the central nervous system creating a host of problems.
• The green you see in the sky comes from Barium. Barium inhaled stays in the lungs. Over time it is known to cause a “benign” cough that just won’t go away known as baritosis. Ingested, it’s a poison that can affect the nervous system and can lead to blindness, irregular hear beat, tremors and more.
• Antimony, which is sometimes used to produce the color white, can harm the lungs, heart, stomach and other organs.
In the last few years, scientists have come up with less toxic alternatives.
DMD Systems, a pyrotechnic research and development company creates fireworks that burn nitrogen-based fuels instead of carbon-based versions, significantly reducing how much perchlorate or other oxidizer is needed. They burn cleaner, produce less smoke, and require less coloring agents. These fireworks contain 10 times less barium than the standard kind, according to DMD.
“Things like barium salt, which is used to make green, or strontium, which is used to make red, usually those are around 25 percent to 30 percent of the weight of a traditional fireworks formula," David Chavez, one of the founders of DMD, said. “But by using a different mix, we found we could drop those amounts by a factor of 10 — down to somewhere between 2 percent and 3 percent.”
At this point, the more environmentally friendly fireworks are many times more expensive than their Chinese counterparts, limiting their use by smaller municipalities. With the possibility of greater regulation, demand for the “greener” product, and subsequent investment into continued development, are predicted by the Wilkin and his colleagues. If realized, less toxic fireworks could become much more affordable and the way of the future. In the meantime, it’s probably a good idea to avoid contact with firework residues.