Fireworks Air Pollution Spikes in USA Post 4th of July

The animation below shows the accumulation of fine particulate (PM2.5) after Independence Day fireworks set off on the night of July 4. In addition to the day long pollution from the barbeque grills and holiday car trips.
The timeline begins in the early hours of July 5, with orange and red colored unhealthy levels continuing through the still night. Many of these metro areas in the Midwest, East and Southeast recently had their air basins flushed clean by winds or rain.

Source: airnow.gov

Testimonials: 
Air Quality Advisory Issued For Smoke and Ozone For July 4 Through July 5 Due to Fireworks
- Clark County Department of Air Quality (DAQ) is issuing an advisory that will be in effect from Friday, July 4, through Saturday, July 5, for potentially elevated levels of smoke and ozone over the Independence Day holiday due to local fireworks.  Air Quality officials say smoke is made of small dust particles and other pollutants that can aggravate respiratory diseases and contribute to ground-level ozone formation.
Fireworks Caused Louisville to Exceed Air Pollution Standards on July 4 For First Time Since 2010
- “Just by the nature of how the standard works, you’d see a spike, you could clearly see a lot of PM in the air, on our monitoring data around 9, 10, 11:00, 12:00, 1:00, 2:00,” he said. “And then it dissipates as people go to bed and they stop shooting fireworks off.” 
Fireworks' 'recreational pollution' makes environmentalists fume
- Fourth of July on the Washington Mall, New York Harbor and countless other cities and towns throughout the US...
... the British medical journal The Lancet points out the "great consequences for health, especially in periods with extremely high particulate matter less than PM2.5 in diameter."
For all their dazzling geometry and stirring booms and crackles, fireworks deliver a smorgasbord of grim chemicals into the skies above.
Perchlorate, the chief propellant, contaminates the ground and water below. It inhibits the thyroid's absorption of iodine...
That brilliant green blossoming above is created with barium nitrate, which is not only radioactive and poisonous...
 Blues are made with copper compounds like polychlorinated dioxins...
The brilliant whites sparkling above are most likely brought courtesy of aluminum compounds, which also bioaccumulate in any living thing below...
 Reds can come from lithium, which is toxic and creates irritating fumes when burned, or strontium...
Add to the palette painting the night sky antimony, rubidium, arsenic, magnesium, potassium nitrate and lead, each producing its twist or effect...
There are also the gaseous by products to be considered. Studies have found spikes in free radical nitric oxide, the highly toxic nitrogen dioxide and acid rainmaker sulfur dioxide following firework shows. Another study found that the ultraviolet light emitted by the flashing light triggers a burst in ozone levels.