“Fireworks for this year’s July Fourth celebration are expected to cause hazardous levels of pollution around the National Mall and ‘very unhealthy’ conditions in central D.C., according to internal National Park Service documents,” the Washington Post reports.“The show, billed by the Trump administration as the largest pyrotechnic display in history, will include some 850,000 fireworks in a roughly 40-minute show expected to start at 10:30 p.m. or 11 p.m… President Donald Trump will speak as part of the event, which marks the 250th anniversary of U.S. independence.”New York Magazine: Trump’s ranting could push D.C. fireworks show to July 5.