For Immediate Release:

September 12, 2025

Public Health Releases Final Findings of Soil Testing in

Fire-Impacted Areas

The Los Angeles County Department of Public Health released the final findings from representative soil sample testing in and around the Eaton and Palisades fire areas, confirming a higher percentage of soil samples with lead levels above health-based screening thresholds from parcels with intact homes downwind of the Eaton Fire.

The final findings also confirmed localized chemical impacts to soil above health-based screening thresholds are present in the Palisades fire area, but there is no evidence of widespread contamination from fire-related chemicals.

Methodology:

The County’s soil sampling was conducted by Roux Associates, Inc., between February 18, 2025 and March 26, 2025. Roux conducted soil and ash sampling for levels of harmful substances that may be present after the recent wildfires—such as heavy metals, polyaromatic hydrocarbons (PAHs), and dioxins/furans – on representative samples from various parcels in different areas and with different property conditions in and around the Eaton Fire and Palisades Fire Regions. Soil samples were collected throughout a sampling grid of each fire area from destroyed and intact properties within the burn areas, as well as from properties just outside the burn areas, and results were compared to current California Department of Toxic Substances Control’s (DTSC) residential soil screening level thresholds.

Eaton Fire

The entire Eaton Fire Region consists of 70 sampling grids, with 23 of those sampling grids containing intact homes (i.e., Minor/Affected Parcels, No Damage Parcels, Outside Fire Boundary Parcels). Of the 23 sampling grids for parcels with intact homes, 10 had average grid concentrations greater than the DTSC residential soil screening level for lead of 80 milligrams per kilogram (mg/kg). The identification of high frequency lead exceedances in soil samples from intact parcels downwind of the Eaton Fire is consistent with reports of elevated lead in air samples collected in the days immediately following the fire. The source of lead in the fire is reasonably expected to be from the burning of homes with lead-based paint, which was common prior to 1979. The University of Southern California Lusk Center for Real Estate reported that more than 70% of the houses within the Eaton Fire Region were built before 1979.

The average grid concentration for lead from the representative sampling of intact homes within the 10 grids that exceeded the residential screening level ranged from 80.2 mg/kg to 167 mg/kg.

However, because there are many potential sources of lead in soil in the Los Angeles area, additional assessments may help understand how much of the lead found in the samples came from the 2025 wildfires versus other sources.

Palisades Fire

The results for the Palisades Fire Region did not identify any large-scale fire-related soil impacts, including for lead. Within the Palisades Fire Region, testing identified two isolated areas where there are sample exceedances (i.e., cadmium and thallium in one area; arsenic and PAHs in another) above applicable soil screening level thresholds. The source of these impacts and whether they are fire-related is unknown at this time, but these are not consistent with communitywide impacts from fire-related smoke plumes.

Additional Findings

Sampling results of parcels with destroyed structures from both fire areas after the United States Army Corps of Engineers (USACE) soil/debris removal showed a significant reduction in the potential health risk where soil removal occurred. Nonetheless, results show that these parcels can still have areas where the concentration of chemicals in soil exceed residential screening levels, both in areas where soil removal did not occur and in areas where soils were removed. Some of these observed soil impacts may be unrelated to fire-related smoke and ash. Soil handing and management during rebuilding should consider how best to manage surface soils to prevent exposure to impacted soils during construction as well as in final landscaping design/installation.

These findings were presented to the public at various Public Health townhall meetings.

This assessment provides a representative analysis of the soil in and around the Fire Regions, for different parcel conditions impacted by the fires. Individual parcels may have unique factors that result in differences compared to these representative samples. The reported results are not intended to imply cleanup or specific remediation is necessary; rather, the

results are intended to provide public health data to help identify areas that may potentially present a health risk and may require additional evaluation.

Those with concerns about their specific property may want to test their soil and/or consult an environmental professional about evaluating their property. In all areas with on-going fire debris, residents are reminded to take precautions to not inhale, ingest, or come into contact with ash, soot, and/or fire debris by using appropriate personal protective equipment. Additionally, community members are encouraged to take appropriate precautions if your home is in one of the areas where soil sample screening thresholds have been exceeded. Residents can refer to Public Health’s Frequently Asked Questions for best practices to minimize exposure to these potential hazards.

The full report is available on our website.