News | USC Dornsife News | March 2026

Eaton fire sent a pollution wave across Los Angeles

The 2025 Eaton fire’s smoke did more than darken the sky: It generated a carbon monoxide and particulate matter surge that far exceeded Los Angeles County’s average daily human-caused emissions, according to a new study led by researchers at the USC Dornsife College of Letters, Arts and Sciences.

Why it matters: The findings show how a major urban wildfire can quickly become a regional air-quality crisis, sending harmful smoke across L.A. and raising concerns about respiratory, psychological and other health effects that Keck School of Medicine of USC researchers are now studying.

What they found: Researchers estimated the Eaton fire produced carbon monoxide at rates more than 20 times higher than L.A. County’s average daily human-caused emissions.