Fireworks are synonymous in the United States with the celebration of Independence Day and other special events, but the colorful displays have caused a growing risk to public safety in recent years, according to a study by environmental health researchers at the University of California, Irvine.
Relying on real-time air quality measurements crowdsourced from a network of more than 750 automated sensors distributed throughout California, scientists from UCI’s Program in Public Health found that short-term, extremely high-particulate-matter air pollution from the widespread use of fireworks spiked during the periods of late June through early July in 2019 and 2020.
The increase was most pronounced in Southern California counties where fireworks regulations are less strict than in northern parts of the state and where the illegal use of do-it-yourself pyrotechnics is also more prevalent. This and other findings are the subject of a study published recently in the International Journal of Environmental Research and Public Health.
“You may have seen discussions on social media lately about people worrying for their pets on nights when the skies are filled with exploding fireworks, but we’ve found that there is a real threat to human well-being too,” said co-author Jun Wu, UCI professor of public health. “And like many other environmental justice issues, we find the worst impacts among residents of low-income communities.”
Aerial explosions cause the release of fine particles less than 2.5 micrometers in diameter. Airborne particulate matter of this size is hazardous because when inhaled, it can be absorbed by the lungs and passed to other tissues inside the body. Fireworks get their distinct colors from compounds containing barium, copper, magnesium, potassium and strontium. As rockets burst in the sky, they release these chemicals, trace redox-active metals and water-soluble ions, which inevitably fall on those below.