July 4th Fireworks Lead to Dangerous Air Quality Levels in California

By: Sam Watanuki | Published: Jul 05, 2024

Independence Day fireworks have led to hazardous air quality conditions across Southern California on Friday, July 5. The South Coast Air Quality Management District (AQMD) has issued a special advisory due to the increased particle pollution.

This advisory impacts parts of Los Angeles, Orange, San Bernardino, and Riverside counties and will be in effect until midnight.

Worst Air-Quality Days of the Year

The AQMD highlights that emissions from July 4th fireworks often result in the worst air-quality days annually. Fireworks release metal pollutants that contribute to the overall particle pollution in the region.

Red, white, and blue fireworks seen during Fourth of July celebrations.

Source: Jim Strasma/Unsplash

This year’s celebration was no exception, with significant air quality deterioration observed early on July 5.

Moderate AQI Levels in South Bay and Orange County

As of 9 a.m. on July 5, air quality in the South Bay and Orange County areas was recorded at a Moderate AQI level.

landscape with air pollution

Source: Freepik

While this is better compared to other regions, it still indicates the presence of pollution that can affect sensitive groups. Residents are advised to stay cautious and limit outdoor activities.

Unhealthy to Hazardous Air Quality in LA and Valleys

Many areas of Los Angeles, the San Fernando Valley, the San Gabriel Valley, and the Inland Empire faced air quality levels ranging from “Unhealthy” to “Hazardous.”

Many cars driving down a Los Angeles street in the daytime.

Source: Lala Miklós/Unsplash

These regions experienced significant pollution due to fireworks, exacerbating existing air quality issues from vehicles and industrial sources.

Glendora and Azusa Experience Hazardous Air Quality

The worst-hit areas on the morning of July 5 included Glendora, Azusa, and parts of West Covina. These locations experienced “Hazardous” air quality levels, making it dangerous for all residents, especially those with pre-existing health conditions.

A huge body of water seen in the daytime with the city of Emeryville seen in the distance.

Source: MicheleKay Saiki-Poaha/Unsplash

The AQMD strongly recommends staying indoors in these areas.

Very Unhealthy Air in Nearby Cities

Cities like Pomona, Montclair, Claremont, Duarte, and Arcadia faced “Very Unhealthy” air quality levels.

Californian flag flying above the clouds

Source: Eric Chan, Wikimedia

This means that the general public may experience health effects, and sensitive groups could face more severe impacts.


San Fernando Valley's Eastern Regions Affected

The eastern San Fernando Valley, including Burbank and Glendale, also recorded “Very Unhealthy” air quality levels.

side view of man walking outside with medical face mask, holding smart phone

Source: Freepik

Residents in these areas should take precautions to protect their health, especially children, the elderly, and those with respiratory conditions like asthma.


Unhealthy Air Across Most of LA

Most of Los Angeles, the rest of the San Gabriel Valley, and the Inland Empire extending to Redlands experienced “Unhealthy” or “Unhealthy for Sensitive Groups” air quality levels.

woman wearing face mask, looking out a window

Source: devmaryna, Freepik

These conditions make it vital for people to limit outdoor activities and follow AQMD guidelines to reduce exposure to harmful pollutants.


Backyard Fireworks Worsen Local Air Quality

The AQMD noted that “backyard” fireworks contribute significantly to local air pollution.

A lot of smoke is pictured exiting a chimney

Source: Freepik

These smaller displays can lead to higher levels of fine particulate matter in neighborhoods, causing even more severe air quality issues than regional measurements might show.


Fireworks Add to Existing Pollution

Fireworks particles add to the existing pollution from vehicles and industrial activities in the Southern California basin.

A photograph of several cars passing quickly along a multi-lane road

Source: Freepik

This combination leads to an overall decline in air quality, making days following July 4th particularly challenging for those with health concerns.


High Ozone Levels Compound the Problem

High ozone levels, unrelated to July 4th celebrations, also contribute to decreased air quality.

A large factory expresses large plumes of smoke next to two ships in the ocean

Source: Chris Leboutillier/Unsplash

This leads to the “Very Unhealthy” AQI levels observed in the afternoon and evening on July 5. Residents should be aware of the compounding effects of these pollutants.


Health Risks and Precautions

The AQMD warns that inhaling fine particulate matter can severely impact cardiovascular and respiratory health. Risks include heart attacks, worsened asthma, decreased lung function, coughing, and difficulty breathing.

A person types on a laptop while a stethoscope lies next to them.

Source: National Cancer institute/Unsplash

To minimize these risks, the AQMD recommends staying indoors, avoiding vigorous physical activity, and using air conditioners and air purifiers to maintain indoor air quality.