Lead Levels in Altadena Soil Exceed Health Thresholds in Wake of Eaton Fire, Final County Report Concludes

Elevated lead levels were detected in soil samples from parcels downwind of the Eaton Fire in Altadena, according to finalized findings released Friday by the Los Angeles County Department of Public Health. The report confirms that 10 of 23 sampling grids with intact homes in the Eaton Fire region exceeded California’s residential screening threshold for lead, set at 80 milligrams per kilogram.

The findings are based on soil and ash sampling conducted by Roux Associates, Inc., between Feb. 18 and March 26, 2025, following wildfires that burned through the Eaton and Palisades regions from Jan. 7 to Jan. 31.

Samples were analyzed for heavy metals, polyaromatic hydrocarbons (PAHs), and dioxins/furans, and compared against thresholds established by the California Department of Toxic Substances Control.

In the Eaton Fire region, 10 sampling grids with intact homes showed average lead concentrations ranging from 80.2 mg/kg to 167 mg/kg. The high frequency of lead exceedances is consistent with elevated air lead levels recorded immediately after the fire.

Public Health officials and Roux Associates believe the source of lead to be the burning of older homes with lead-based paint, which was common prior to 1979, according to the report.

According to the University of Southern California Lusk Center for Real Estate, more than 70% of homes in the Eaton Fire region were built before that year.

Soil sampling of parcels with destroyed structures following debris removal by the U.S. Army Corps of Engineers showed a significant reduction in potential health risks, according to the report. Nonetheless, some parcels still contain areas where chemical concentrations exceed residential screening levels, including locations where soil removal occurred.

In the report, County Public Health recommended that soil handling during reconstruction should minimize exposure to the affected surface soils, both during construction and in final landscaping.

The County said that residents concerned about their specific properties are encouraged to conduct individual soil testing and consult environmental professionals.

The finalized report is online here.