District records annual July 4 spikes
VENTURA — As the Fourth of July approaches, people in sensitive groups should be cautious about elevated levels of air pollution caused by fireworks.
Fireworks emit fine particles including soot and ash that can cause serious health effects. Children, older adults and people who are pregnant or have respiratory or heart conditions are the most at risk.
Historic patterns recorded by Ventura County Air Pollution Control District (VCAPCD) monitors indicate that areas close to heavy fireworks experience air pollution levels that are unhealthy for sensitive groups, according to the Air Quality Index (AQI). In 2025, the level of fine particulate matter, or PM2.5, that was recorded for a couple of hours on the night of July 4 in Simi Valley would be considered unhealthy for sensitive groups if maintained for a 24-hour period. The Simi Valley monitor is located two blocks east of the 2025 fireworks display at Rancho Santa Susana Community Park.
Also in 2025, a monitor in Piru, which is near Fillmore where personal use of “Safe and Sane” fireworks is allowed, indicated the amount of PM2.5 came close to the unhealthy-for-sensitive-groups level on the evening of July 4. In 2025, the Thousand Oaks monitor recorded slightly lower levels than Piru on the evening of July 4 and morning of July 5.
The city of Agoura Hills will present a lower-emission alternative to fireworks, a Patriotic Drone Show, after the Summer Concert in the Park on Sunday, July 5, at Chumash Park.
PM2.5 particles are small enough to penetrate deep into the lungs and enter the bloodstream, increasing the risk of heart attack and stroke. The particles can irritate throats, lungs and sinuses and cause headaches, fatigue, coughing, wheezing, shortness of breath, asthma attacks and dry, watery eyes.
Toxic metals like strontium and barium produce the vibrant colors seen in fireworks. Illegal fireworks may contain additional toxic metals, including lead.
When air quality reaches an unhealthy level, people should:
- Stay indoors as much as possible, preferably in a “clean room” with an air filter.
- Close all windows and doors that lead outside unless it is extremely hot.
- Operate home and car air conditioners in recycle or recirculation mode.
- Avoid strenuous outdoor activity.
- Consider wearing a properly fitted N95 mask when outside.
For real-time data, check the AirNow NowCast AQI at www.airnow.gov or fire.airnow.gov