Tracking the Hidden Dangers in Wildfire Smoke: Scientists Push for Better Air Monitoring After LA Fires
When massive wildfires tore through Los Angeles, environmental health professor John Volckens at Colorado State University suspected the smoke held more than just soot. Homes, buildings, and vehicles were incinerating, potentially releasing a cocktail of hazardous chemicals into the air. But how dangerous was it really?
Determined to find out, Volckens quickly sent 10 air quality detectors to Southern California. His mission: measure the levels of harmful substances like heavy metals and benzene — toxins not typically detected by standard air quality systems.
These fires destroyed over 16,000 structures and rank among the most expensive natural disasters in U.S. history. Volckens’ initiative came from a concern echoed by many: What exactly are people breathing in during these increasingly frequent wildfires?
“We go through these traumatic events, and then we’re left wondering what toxins we’ve inhaled,” Volckens said. He shared his findings with local air authorities to help guide public health responses.
The Air Quality Index: Incomplete During Crisis
Traditional air pollution monitoring — like the Air Quality Index (AQI) — is a useful tool for general conditions. But during disasters, it falls short. According to UCLA environmental health professor Yifang Zhu, AQI readings can appear safe even when wildfire smoke contains toxic chemicals invisible to these monitors.
This growing concern has triggered a broader call to action. Lawmakers and public health advocates are urging the EPA to strengthen wildfire air monitoring. A bipartisan push includes legislation to fund local agencies, expand air sensor deployment, and educate communities about wildfire smoke hazards.
A Technological Response to a Health Crisis
Volckens’ devices, called AirPens, began collecting data just days after the fires broke out. Small enough to fit in a plastic housing the size of a loaf of bread, these tools were placed around the city — from the fire’s edge to urban areas like Santa Clarita and West LA.
Unlike traditional stations, these portable monitors tracked dozens of pollutants in real-time. The data was sent to labs weekly, analyzing dangerous compounds such as black carbon, benzene, lead, and other volatile organic compounds. The results gave authorities and residents a clearer picture of health risks during and after the fire.
The South Coast Air Quality Management District also stepped up efforts by deploying mobile monitoring vans and installing additional neighborhood sensors to improve tracking during debris cleanup.
“One sensor can’t do it all,” said Jason Low from South Coast AQMD. “We need multiple tools to get a complete picture.”
Chemical Spikes and Community Risk
Evidence gathered by ASCENT — a national network of air quality monitors funded by the National Science Foundation — revealed alarming results. Near the San Gabriel Mountains, sensors recorded chlorine levels 40 times higher than normal and lead levels 110 times above typical levels after the fires.
These pollutants weren’t from natural materials like trees. They came from synthetic and urban materials burning — a signature of wildfires in developed areas. Researchers like Caltech’s Richard Flagan emphasize the importance of real-time chemical data for health experts and epidemiologists working on long-term health impact studies.
A Push for Better Tools and Public Access
A 2024 report by the U.S. Government Accountability Office (GAO) highlights the role of small, low-cost sensors in closing gaps left by older government equipment. These devices can detect PM2.5 (fine particles) effectively and help identify pollution hotspots — but they still struggle with many airborne toxins that require expensive, lab-grade analysis.
“Low-cost sensors have improved, but their ability to detect all toxins is still limited,” said J. Alfredo Gómez, director at GAO.
Still, experts like UCLA’s Zhu see a future where ordinary residents could install these tools in their own backyards — empowering communities with better information when it matters most.
“With wildfires likely to worsen, investing in these technologies could help families make safer choices in real time,” Zhu said.
Conclusion
The Los Angeles wildfires exposed major gaps in the country’s ability to monitor dangerous air pollutants during disasters. With climate change fueling more frequent and intense wildfires, the need for faster, more accurate, and accessible air quality monitoring is critical — not only for researchers but for the people breathing that air.
