Soil testing finds elevated metals at some Malibu fire-damaged properties

By Judy Abel · Sun Jul 19 2026

Community-led study detects arsenic and lead at some Palisades Fire homes, but researchers say residents shouldn't panic

As thousands of residents plan to rebuild following the January 2025 wildfires, one of the largest community-led environmental testing efforts ever conducted after an urban wildfire is helping homeowners answer one pressing question: Is my property safe?

The Community Action Project Los Angeles (CAP.LA) has now completed soil sampling at 3,423 residential properties in the Palisades and Eaton burn zones, collecting more than 9,000 soil samples and analyzing them for 17 metals associated with wildfire contamination.

Within the Palisades burn area alone, researchers tested 1,397 properties. Results showed that 321 properties had arsenic levels at or above the area's naturally occurring background level of 12 parts per million (ppm). Researchers also found 175 properties with lead levels above California's health screening level of 80 ppm, while 39 properties exceeded 200 ppm for lead.

The project uses California's more protective health screening levels whenever they are stricter than federal standards. For lead, California recommends a screening level of 80 ppm, while the U.S. Environmental Protection Agency's benchmark is 200 ppm.

Arsenic presents a different challenge because it occurs naturally throughout much of the Santa Monica Mountains and Malibu area. Rather than comparing every property to zero, researchers used a background level of 12 ppm established through previous geological studies. "Arsenic is naturally occurring in that area," said Brianne Gilbert, managing director of the Center for the Study of Los Angeles (StudyLA) at Loyola Marymount University, which partnered with UCLA on the project. "You could have had that same level before the fire and simply not known because it was part of your normal soil."

In some cases, elevated arsenic may also reflect a property's history rather than the wildfire itself. Gilbert explained some homeowners discovered contamination only in isolated portions of their property and later realized old storage sheds containing decades-old weed killers had burned there. Historically, many herbicides contained arsenic, which may have been released into surrounding soil during the fire.

Despite these findings, project leaders caution against drawing a simple conclusion that homes with elevated levels automatically require expensive cleanup. "There really isn't a level where we would say, 'Now you need to be concerned,'" said Gilbert of misconceptions that a laboratory result automatically determines whether remediation is necessary. "If you have arsenic at 13, do you need to be concerned? We don't put a value on how concerned homeowners should be," she said. "That's really up to each individual homeowner.” Instead, researchers encourage residents to look at how they use their property before deciding whether remediation makes sense.

A yard where young children regularly play, pets spend time outdoors or vegetables are grown may warrant a different response than an ornamental landscape that is rarely disturbed. "It's really about understanding how people interact with their soil," Gilbert said.

Gilbert stressed that the testing program was designed to provide information — not directives. "We don't have a line where we say, 'These people should be concerned and these people are totally fine,'" she said. "There's a whole lot of gray area depending on people's interpretations and how they use their property."

That information has already helped many residents avoid unnecessary expense. Some homeowners told researchers they had been quoted more than $10,000 for private soil testing before CAP.LA offered the service free of charge. "If we can show a homeowner that nothing on their property tested above the health screening level, then they know they don't need to spend that kind of money on additional testing," Gilbert said. Unfortunately for homeowners interested in free testing, the CAP.LA program has exhausted its funding. Another program, USC CLEAN, funded by FireAid and LA Care, accepts soil samples by mail or at designated drop boxes.

For homeowners whose properties do show elevated levels, some may choose to consult environmental remediation specialists, while others may determine that contamination is limited to an area of the property that poses little risk.

The collaboration of researchers involved in the soil testing evolved into CONSORTIUM — the Community OrientedNetwork for Scientific Observation, Recovery, and Tracking of Impacts from Urban Megafires. This group brings together researchers from UCLA, Loyola Marymount University, USC, Harvard University, UT Austin and several community organizations to coordinate wildfire recovery research.

Gilbert, a social scientist who coordinated homeowner enrollment and communications, said the project's greatest success may not be the data itself, but the reassurance it has provided. "My favorite takeaway is getting emails from homeowners expressing their gratitude," she said. "They can look at their results and say, 'This is manageable. This is doable.' They know this doesn't have to be their biggest worry."