Preliminary soil testing in the aftermath of the Palisades and Eaton wildfires has uncovered isolated pockets of chemical contamination in the Palisades area, prompting calls for further investigation and targeted environmental assessments, officials from the Los Angeles County Department of Public Health said on Friday.
The findings, based on representative soil sampling conducted by environmental firm Roux Inc., were presented during a public briefing held over Zoom and reflect approximately 90 percent of the test data collected to date. The study focused on intact residential parcels within and near the burn zones, where samples were taken in an effort to evaluate soil conditions following the fires.
In the Palisades area, testing identified specific locations where arsenic, cadmium and polycyclic aromatic hydrocarbons (PAHs) – chemicals commonly associated with combustion and industrial activity – exceeded established health-based screening thresholds. These exceedances were not widespread, but were concentrated in two distinct areas: a northeastern cluster where arsenic and benzo[a]pyrene were elevated and a southwestern zone near the ocean where cadmium levels were higher than recommended.
Environmental consultants collected nearly 4,000 soil samples from around 800 intact residential parcels in the Eaton and Palisades fire areas between late February and late March. Using standard methods, five samples were taken from the top three inches of soil at each property. The goal was to capture a representative snapshot of post-fire soil conditions both inside and just beyond the burn zones. Samples were analyzed for heavy metals, PAHs and dioxins, then compared against state and federal residential screening thresholds. Officials noted most exceedances were minor, with a few likely tied to unrelated local sources rather than wildfire fallout.
Dr. Brett Love, who presented the data, said the chemical distribution did not match patterns typically associated with wildfire smoke or ash dispersal. Instead, the concentrations suggest more localized sources that may predate the fire, though the origin remains unknown.
“This doesn’t look like a general plume effect,” Love said. “It’s not something that affected the entire Palisades area. These appear to be isolated hotspots that warrant closer study.”
The presence of contamination in the Palisades zone came as a surprise, especially given the relatively low lead levels found there. By contrast, soil samples from the Eaton fire area revealed a higher percentage of lead exceedances, particularly in areas downwind of where homes were destroyed. Up to 40 percent of samples from those parcels surpassed state or federal screening levels. Officials attributed the elevated lead levels to the likely presence of lead-based paint in older homes, consistent with housing stock built prior to 1979.
Although lead is a known post-fire contaminant, health officials emphasized that screening thresholds are designed to protect vulnerable populations over long-term exposure and are not cleanup mandates. Dr. Nicole Quick, chief medical advisor for the Los Angeles County Department of Public Health, said the results offer a snapshot of general conditions but cannot predict contamination on any specific property.
“These results are meant to guide further evaluation, not to trigger immediate remediation,” Quick said. “Residents who are concerned about their soil should consider consulting an environmental professional.”
A final report is expected in May. In the meantime, county officials are requesting additional support from state and federal agencies to conduct follow-up sampling in the Palisades area and expanded lead testing near the Eaton fire.
Health officials said the pattern of contamination did not indicate widespread fallout from Palisades wildfire smoke, but likely pointed to localized sources that may predate the fire. No public health advisory has been issued for the neighborhood, though officials encouraged residents near the identified hotspots to stay informed and take basic precautions when working with soil. Further environmental assessment is planned and residents with specific concerns are advised to consult professionals for parcel-level evaluation if needed.
