Bernadette Tansey, Chronicle Staff Writer
Thursday, July 3, 2008
All of us are looking forward to the annual July Fourth fireworks, with their glittering starbursts of red, blue and green.
But chemists are actually trying to make our annual fireworks extravaganzas much greener. A big fireworks show can release poisonous chemicals over land and water, they say, with effects on people and wildlife that have not been fully evaluated.
"Fireworks, though spectacular and entertaining, are a source of concern because of environmental pollution," concluded two university scientists in Germany, Georg Steinhauser and Thomas Klapotke, in a recent review of efforts to produce less toxic pyrotechnics. People who raise concerns about toxins in fireworks, however, risk being branded as fanatical killjoys - even in environmentally conscious California. Bruce Reznik, executive director of San Diego Coastkeeper, said the group was treated like it was "stealing Christmas and apple pie" when it pressed state agencies to assess the environmental impact of year-round fireworks shows at the popular SeaWorld San Diego theme park.
"We took a lot of heat," Reznik said. A similar furor arose when the California Coastal Commission barred Gualala from holding a July Fourth fireworks display this year at a site where the noise might frighten seabirds away from their nests. Fireworks are fiercely defended as symbols of every innocent cause for celebration, from romance to national pride.
"You all are the nanny state," said Julie Heckman, executive director of the American Pyrotechnics Association, a trade group for fireworks businesses. "How much more can we impose on our freedoms?"
However, no less patriotic an institution than the U.S. military is seeking more eco-friendly pyrotechnics. The same environmental concerns are common to both fireworks and military equipment such as signaling flares and airborne weapons. Defense agencies are financing research by scientists including Steinhauser and Klapotke in Munich and explosives experts at Los Alamos National Laboratory in New Mexico. Among the concerns is the cumulative contamination of military testing grounds and training sites.
As the science advances, a fledgling "green pyrotechnics" industry has also sprung up to serve big entertainment businesses such as Disneyland Park in Anaheim, where neighbors' complaints about smoke from frequent fireworks shows prompted the Walt Disney Company to redesign its displays. So far, the market for the expensive new technology is confined to big show-business concerns that put on indoor concerts or wrestling matches where air quality is particularly important, said Darren Naud, a former Los Alamos lab explosives expert who co-founded a company called DMD Systems to serve Disney and other clients.
Naud said the greener fireworks won't achieve a broader consumer market unless regulators tighten restrictions. "If the regulations are not there, people will continue to buy the cheaper stuff," he said.
What worries chemists about conventional fireworks are three kinds of compounds. Flaming combustible elements give off smoky gases and fine particles that might penetrate the lungs. Metals such as barium and strontium add colors to the glittering flames. A third ingredient, perchlorate, promotes burning and supplies chlorine to heighten color. Perchlorate seeps readily through groundwater and is linked to malfunctions of the thyroid and birth defects.
Exploding this mixture of chemicals together may yield new compounds carrying health risks, including dioxins and other powerful cancer-causing substances, Steinhauser and Klapotke said in their February review article in the scientific journal Angewandte Chemie. Poisonous barium compounds can affect the heart and lungs, they said. But few studies have looked at whether the fallout from fireworks leaves harmful concentrations of toxins.
The trade group for fireworks businesses, the American Pyrotechnics Association, maintains that audiences attending the local July Fourth fireworks show have nothing to worry about. "Most communities have a few shows maybe once a year," said Heckman, the group's executive director. Heckman said most fireworks ingredients are consumed in the explosion and quickly dissipate. "The level of contamination is going to be nonexistent, or nominal."
Steinhauser and Klapotke found studies suggesting that fireworks ingredients can cause human health impacts when people undergo intense exposure. One paper noted an increase in asthma during the Indian Diwali festival of lights, and others reported diseases of the lungs, kidneys and other organs among overseas fireworks manufacturing workers.
The vast majority of fireworks used in the United States are imported from China. Many U.S. regulatory agencies oversee the fireworks industry, but they focus on making sure the products can be shipped without exploding and used without blowing off any fingers. In recent years, however, health and environmental concerns have surfaced in California where fireworks are intensively used or were manufactured.
In 2002, the city of Rialto and nearby towns shut down 22 wells contaminated by groundwater plumes of perchlorate spreading from two sites where fireworks and other products had been manufactured decades ago.
In December, the San Diego Regional Water Quality Board required SeaWorld to monitor levels of perchlorate and 40 other components of fireworks in Mission Bay, the aquatic inlet where SeaWorld can hold 150 fireworks shows a year. That permit requirement - the first in the nation - was a victory for San Diego Coastkeeper, which had urged state agencies for years to evaluate the environmental impact of repeated pyrotechnic displays.
"We're not saying nobody should have fireworks," said Reznik. "We're saying let's look at them and see if there's any impact, and if there is maybe they can be changed and be more environmentally friendly."
So far, no danger signs of fireworks-related pollution have turned up in monitoring tests of San Francisco Bay, said Dyan Whyte, assistant executive officer at the San Francisco Regional Water Quality Control Board.
"If it doesn't look like a problem, we don't need to be out there ruining people's Fourth of July," she said. But the water agency will evaluate SeaWorld's studies, and keep an eye on the issue, she said. "This may be one that we need to take a closer look at, at some point."
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