Fireworks are beautiful – right? Your lungs would like to disagree.

Let’s get into the science behind the sparklers and find out:

• what airborne pollutants fireworks produce
• how fireworks shows impact air quality and your health
• what you can do to protect yourself from fireworks air pollution

What are fireworks made of?

Every firework relies on a series of chemical reactions to achieve a certain size, color, or loudness. These chemicals are packed into a tube called an aerial shell that’s packed with chemicals and explosives.

Here’s the ingredient list for a typical firework.

Black powder

Sometimes called gunpowder, black powder helps the firework get into the air and blow up.

Black powder is a mixture of sulfur, charcoal, and potassium nitrate (also called saltpeter). It’s used in two important parts of the firework process:

1. Gunpowder blows up below the firework and propels it into the air.
2. A fuse that’s designed to delay until the firework’s in the air ignites the gunpowder, resulting in the explosion that creates the firework display.

Colorants

These are chemicals that help give fireworks their wide range of colors. Fireworks achieves certain colors and shades by applying heat to chemical compounds:

• Red: strontium, lithium
• Orange: calcium, calcium chloride
• Yellow: sodium, sodium chloride (salt)
• Green: barium, chlorine
• Blue: copper, chlorine
• Purple: mixture of copper (blue) and strontium (red)

“Stars”

These are the small concentrations of explosives in a firework that blow up and fly in many directions when ignited.

Notice how a firework looks like a bunch of long, bright light rockets? Each light results from a single “star” in the firework shell.

Stars can also be arranged in shapes inside the aerial shell so that they look like happy faces, hearts, or other shapes when they explode.

Do fireworks cause bad air quality?

Remember that fireworks are basically explosions of chemicals in solid form. Millions of combustion particles and gases are released into the air during these splashes of color on the sky. Many are also blown around for miles in atmospheric wind currents.

The most notable fireworks pollutant, particulate matter (PM), includes three distinct types of particles:

• PM10: coarse particles ranging from 2.5–10 microns in diameter, such as dust, mold, and pollen
• PM2.5: fine particles ranging from 0.3–2.5 microns in diameter, such as those created from combustion in vehicle engines or factory emissions
• Ultrafine particles (UFPs): tiny particles smaller than 0.3 microns in diameter – UFPs make up over 90% of all airborne particle pollution and are by far the most dangerous PM pollutant
• Volatile organic compounds (VOCs): airborne vapor or gaseous compounds responsible for odors that are produced by chemical reactions in combustion, manufacturing, or industrial processes.

Fireworks generate huge concentrations of pollutants from colorants and explosives as well as from the metals and fuses that make up the firework itself.

One study conducted in Albany, New York, right after a celebration found that PM pollutant concentrations can be up to eight times higher than normal in the hours right after a fireworks show – and up to 10 times higher than even pollution from vehicle traffic in the same area.¹

The study also pointed out that wind conditions can cause those pollutants to stay in the air for as long as five hours after a fireworks show – and up to 77% of the particulate pollution in the air originates from those fireworks alone.

Other studies have shown similar increases in local air pollution right after a fireworks show and specified what exactly gets into the air after a few fireworks explosions:

• A 2007 study of fireworks during the lantern festival in Beijing, China analyzed the exact chemical reactions that occurred during a fireworks display – researchers found that fireworks resulted in five times the normal amount of PM and dangerous chemical pollutants in the air like nitrogen dioxide (NO₂) and sulfur dioxide (SO₂).²
• A 2014 study in Agra, India of fireworks pollution after the annual Deepawali “festival of light” found that toxic airborne pollutants from fireworks like PM, SO₂, NO₂, and ozone (O3) spiked as high as 293.5 μg/m³ for up to five days after fireworks shows ended – more than 2,800% higher than the limit recommended by the World Health Organization (WHO).³
• A 2015 study of air quality at 315 locations around the United States after July 4^th Independence Day celebrations found PM2.5 increases from 42% to 370% during a fireworks show, with the biggest jumps occurring around 9-10PM and lasting sometimes until noon on July 5^th.⁴
• A 2019 study of air quality in the Netherlands after New Year’s fireworks shows found that PM10 concentrations skyrocketed, on average, from around 29 micrograms per cubic meter (μg/m³) to 277 μg/m³ during the first hour after the show, an 855% increase – and in some places, as high as 598 μg/m3 (a nearly 2,000% increase!).⁵

Fireworks and air quality in 5 major U.S. cities during 4^th of July

Need proof that fireworks can cause huge spikes in air pollution? Look no further than 4^th of July, one of the world’s holidays most associated with huge firework shows.

Air quality data from five major U.S. cities around the July 4th Independence Day holiday from 2016 to 2019 backs up the claims in much of the fireworks air pollution research.

Here’s what air quality data show in 5 major U.S. cities – Chicago, Las Vegas, Los Angeles, New York City, and Washington, D.C. – around the 4^th of July holiday.

Chicago

Figure 1: Chicago, IL – PM2.5 levels spiked as high as 529% in the late hours of the 2018 Independence Day holiday (gray), with an average increase of 387% over four years during each July 4^th holiday.

Las Vegas

Figure 2: Las Vegas, NV – in 2016 (dark orange), PM2.5 levels shot up a shocking 1522% during Independence Day – and the city averaged a 915% increase in PM2.5 each July 4^th holiday over a four-year period.

Los Angeles

Figure 3: Los Angeles, CA – in a city already known for its year-round smog, PM2.5 levels shot up as high as 878% in 2017 (dark orange), with a four-year average PM2.5 increase of 451% during the July 4^th holiday.

New York City

Figure 4: New York, NY – in 2017 (dark orange), PM2.5 levels rose 618%, and rose about 394% on average during the 4^th of July holiday. In 2018 (gray), PM2.5 levels were already elevated for several days leading up to July 4^th before increasing a total of 313% overall.

Washington D.C.

Figure 5: Washington, D.C. – PM2.5 increased an average of 316% over the past four years during the July 4^th holiday season.

Does fireworks air pollution cause health problems?

If you have a respiratory condition like asthma, chronic obstructive pulmonary disorder (COPD), or chemical sensitivity, you probably already know the kind of symptoms that chemicals from a fireworks show can cause – shortness of breath, coughing, and chest pain.⁶

But fireworks can be harmful even if you don’t have any existing respiratory issues. Some of the symptoms you might experience because of poor air quality caused by fireworks include:^7,8

• headaches
• anxiety from nervous system effects
• sore or swollen throat
• airway inflammation
• laryngitis
• having trouble breathing
• high blood pressure
• irregular heartbeat
• reduced lung function
• pneumonia
• heart attacks

And even though fireworks only result in temporary increases in local air pollution, fireworks air pollution can travel for miles and cause bad air quality around the world, making the effects of air pollution more severe even in regions that never see a fireworks show.

How do I protect myself from fireworks air pollution?

The good thing about fireworks is that they’re usually temporary and can be easily avoided. Here are some tips for protecting yourself from the air pollution caused by fireworks:

• Use safe alternatives to traditional fireworks. Some of the world’s biggest buyers of fireworks, such as the Walt Disney Company, have received thousands of complaints about air pollution caused by their infamously theatrical nighttime shows at their theme parks in Anaheim, Orlando, and Hong Kong. In response, the company introduced fireworks that use compressed air instead of gunpowder.9 Some cities, like Aspen, Colorado and Shanghai, China are also seeking to use drones equipped with colored lights to create formations that are visually similar to fireworks to vastly reduce air pollution during holiday celebrations.^10,11
• Voice your concerns to officials. Live near a major source of fireworks? Some governments make concessions to businesses that host regular fireworks shows because they’re a big source of local revenue. Share your experiences and concerns with lawmakers regarding health effects of fireworks. Get others involved who may be experiencing the same issues. This can help change policy by limiting fireworks shows or ending them altogether.
• Shut your windows and doors. If you’re at home and live close to an area that has regular fireworks shows, close windows, doors, and any other openings in your home right before the fireworks start. Don’t open them again for a few hours, as fireworks pollution can linger and travel many miles for hours after the show ends.
• Purify the indoor air. Airborne pollutants from fireworks shows can still seep into your home even with everything closed up. Filter the air to capture any particulate and gas pollution that gets into your home, deliver fresh air into your indoor environment, and keep your indoor air quality safe. This Help Me Choose can help you find the right air purifier for your needs.

The takeaway

Many of us enjoy a good fireworks show and can’t remember a holiday celebration or theme park trip without one.

But the truth is that fireworks add a significant amount of air pollution into your local atmosphere. These pollutants can last for hours or days on end, exposing you and your neighbors to possible long-term health effects.

You can either move away, take precautions to protect yourself, or do something about it – fireworks shows may never go away, but there’s plenty you can do to help yourself and others confront the unique air quality problems associated with fireworks.