DC's 250th July Fourth fireworks could spike air pollution

The National Park Service will stage a record-setting 850,000 fireworks display over Washington, D.C. for the 250th anniversary, with internal air-quality drafts warning of hazardous fine-particle pollution and potential perchlorates/heavy metals entering the Potomac; the EPA says it isn’t issuing permits or tracking air quality. Past large displays have shown PM spikes that can linger for about 24 hours, prompting health guidance to avoid prolonged exposure and consider N95 masks, while drought and heat could prolong pollutant residence and threaten wildlife like ospreys. Officials emphasize precautionary measures (distance, indoor air filtration, masks) even as the broader show area expands beyond the National Mall.