The National Park Service has warned internally that President Donald Trump’s supersized Independence Day fireworks show could create dangerous air pollution conditions across the nation’s capital.
Trump has boasted that the historic event will set records, unleashing more than 850,000 pyrotechnics over downtown Washington and the Potomac River to celebrate the nation’s 250th birthday.
The display represents a hundredfold increase over the city’s normal Independence Day show, compressed into a 35-minute program planned for the National Mall.
In its worst-case scenario, the National Park Service estimated the fireworks would generate more than 2,000 micrograms of fine particulate matter, known as PM2.5, per cubic meter on the Mall.
Low-wind conditions currently expected as Washington swelters under a heat wave could trap smoke over the National Mall and cause pollution to “reach extreme hazardous levels,” the Park Service warned.
A draft air-quality analysis from May advises that people should “avoid prolonged exposure” to the fine particulate matter pollution, including by wearing N95 masks “when outdoors.”
Downtown Washington, Arlington, and Capitol Hill were each projected to experience “very unhealthy” conditions, with elevated pollution levels expected to linger for three to six hours after the show concludes.
There are no indications that the administration plans to recommend masking or other personal protection measures for the large crowds expected to gather on the National Mall for the festivities.
The Environmental Protection Agency distanced itself from the air quality concerns, with spokesperson Mike Bastasch stating in an email: “First off, fireworks are awesome and we hope everyone enjoys the incredible shows in and around our nation’s capital as we celebrate 250 years of America. The EPA is not issuing permits for the fireworks for this event.”
George Thurston, a professor of medicine and population health at New York University, said the projected pollution levels are severe enough that people should “minimize exposures” to outdoor air during the show, adding that wearing “an N95 mask would be a good idea.”
Thurston also raised concern about Washington residents in low-income neighborhoods, which are disproportionately exposed to environmental pollutants and could be particularly vulnerable to the hazardous air quality generated by the event.
Beyond air quality, the massive scale of the show risks depositing water pollutants including perchlorates and heavy metals into the Potomac River, the effects of which on human health and the environment remain poorly understood by scientists.
One study found that particulate matter from July Fourth fireworks remained elevated for roughly 24 hours across 315 monitoring sites, with fireworks displays increasing pollution by an average of 42 percent before dissipating into water and soil.
The National Park Service and Freedom 250, the Trump-aligned organization helping coordinate the event, did not respond to requests for comment on the internal warnings.
