soil toxicity
When a home burns, materials like car batteries, lead paint, major machinery, and appliances create a noxious cloud of dangerous substances. Unfortunately, many of those chemicals can persist in soils.
Unless you have already tested, there’s a chance your land still holds contaminants that could affect your family’s health and the value of your property.
Here’s a quick guide to what you need to know and what to do about it.
*This guide is built on the work of the sources at the bottom of the page, including CAP.LA,UCLA, USC, Harvard, Yale, Purdue, Loyola Marymount, UC Riverside, and others.It has been checked for accuracy by Dr. Sanjay Mohanty of UCLA, lead researcher at CAP.LA; This guide should not be taken as medical or legal advice.
Consult with a licensed professional about the specifics of your situation.What Are The Dangers?
Note: Some of these substances are naturally occurring or were already present in soils, pre-fire. What to keep an eye on are when levels exceed safety thresholds, and the duration of exposure needed for dangerous effects to occur.
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Lead, especially, is dangerous for kids and pets - it can be tracked in on shoes, licked off paws, or spread through dust.
Can damage the brain: trouble with learning, thinking, and memory, especially in young children, as their brains are still developing.
Can weaken blood production → possible anemia (less oxygen in the body).
Can cause digestive and nervous system issues: upset stomach, weakness, tremors.
Builds up over time - small exposures can accumulate and cause harm because the body doesn’t get rid of lead quickly.
Source: National Library of Medicine
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Skin problems: patches, discoloration, hard or thick areas.
Increased risk of cancers (skin, lung, bladder) with long-term exposure.
Harm to organs: liver, kidneys, and heart can be damaged over time.
In children, slow growth or developmental delays may occur if exposed early or for a long period.
Source: World Health Organization and National Library of Medicine
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If fibers are breathed in, they can lodge in the lungs permanently. Over years, this can lead to lung scarring (asbestosis), difficulty breathing.
Causes cancers like mesothelioma (lining of the lungs or chest cavity), which is very serious.
Pets are also at risk — dogs, cats (and other animals) can develop mesothelioma when exposed to asbestos fibers.
Source: CDC, Agency for Toxic Substances and Disease Registry, and Animal Health Foundation
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Recognized as a strong carcinogen when inhaled: increases risk of lung cancer.
Can cause skin irritation, ulcers, and respiratory allergic reactions if one comes into contact via air or dust.
Source: Cal OEHHA, National Library of Medicine, OSHA, National Institute of Environmental Health Sciences, US EPA
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Lithium can be present in soil or dust after fires involving batteries and electronics. It can be tracked indoors on shoes or paws or accidentally ingested on dirty hands.
Can affect the nervous system: confusion, drowsiness, tremors, and poor coordination at high exposures.
Can impact the kidneys; long-term exposure to high levels can strain kidney function.
Can affect the thyroid; may disrupt hormones that regulate metabolism and energy.
Can cause digestive symptoms: nausea, vomiting, and diarrhea at elevated exposures.
The body does remove lithium, but repeated exposure to high levels can still cause harm over time.
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Thallium is highly toxic to people and animals - it can be present in contaminated soil or dust and be tracked indoors on shoes or paws, or accidentally ingested on dirty hands.
Can damage the nervous system: nerve pain, tingling, weakness, and problems with movement or coordination.
Can affect the stomach and gut, including nausea, vomiting, diarrhea, and abdominal pain.
Can cause hair loss: a well-known sign of thallium poisoning after repeated exposure.
Can affect organs like the liver and kidneys with ongoing exposure.
Builds up over time; the body removes thallium slowly, so repeated small exposures can accumulate and become harmful.
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Many PAHs are carcinogenic or suspected carcinogens (linked to cancers).
Can cause respiratory problems: inflammation of airways, worse asthma or coughing.
May harm unborn babies / cause low birth weight when pregnant people are exposed.
Source: National Library of Medicine, Agency for Toxic Substances and Disease Registry
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Short-term effects: irritation of eyes, nose, throat; headaches; dizziness; nausea.
Long-term: some VOCs damage the liver, kidneys, or the central nervous system. Some are possibly or definitely cancerous.
Pets are also sensitive: breathing problems, behavioral changes could result from high exposure.
Source: American Lung Association
How Contamination
Can Affect
Property Value
By law, you must disclose past fire damage and known contamination when selling a property in California.
Buyers, lenders, and insurers may ask for proof that your soil is free of contamination. If you can’t provide test results or documentation of remediation, you may face lower offers, delays, or outright refusals.
Note: If your property tests positive for contaminants, you are required to disclose that in the event of a sale. If you have not properly remediated, it could affect your property value or ability to sell.
Get A Test
Testing is the only way to know your land is truly safe for you, your family, and anyone who may live there in the future.
Hire a certified lab to come on-site and collect samples. Experts recommend that you don’t rely solely on self-submitted samples if at all possible. Recommended testing includes:
CAM17 heavy metals
Lithium
Cr6 (Hexavalent Chromium)
PAHs (Polycyclic Aromatic Hydrocarbons), if available
Ask the lab to include chain-of-custody documentation with your results.
TIP:
If you are part of a lawsuit (like against SCE), your attorney may cover the cost of your soil testing as part of your case costs.
You may have to pay for this out of any settlement you receive, but it could possibly save you some up-front costs.
something to know about self-submitted tests
CAUTION
Some emerging contaminant findings raise different health risks than previously discussed contaminants because they can be taken up via the skin.
Please be cautious when exposing yourself to untested/unremediated soils and stay abreast of testing updates via CAP.LA.
If you are unable to access professional testing, you can self-submit samples to USC’s free CLEAN program or the Department of Public Health, but a few things to note:
A negative result from a self-submitted test is not an indication of a toxin-free lot.
These programs only test for lead, which is one of several contaminants that can be present on your property.
Collecting soil samples yourself can expose you to toxins. Be sure to wear proper PPE if you pursue this method.
To obtain a remediation plan, a professional test will be necessary.
A self-submitted test will not suffice for legal claims for damages, so if you plan to claim the cost of testing or remediation, a professional test (with chain-of-custody) will be required.
What you’re
looking for
When your soil test results come back, you’ll looking for “exceedances”.
An “Exceedance” is when the levels are higher than what the California EPA deems safe for you to be exposed to. These are called “Residential Screening Limits” and are different State by State.
For example:
“If your results show lead (Pb) at “100 ppm”, and the California residential screening limit for lead is 80 ppm, then that sample exceeds the guidelines and is considered contaminated.”
- Dr. Danielle Stevenson, CAER
If the lab did not specify what your exceedances are, call and ask them to clarify.
If Your results
shows exceedances
The lab will likely give you a breakdown of their findings and some may make remediation recommendations in their report.
If they do not give you remediation recommendations, having a Certified Industrial Hygienist or residential soil specialist decipher the results may be helpful.
In California, you can find an Industrial Hygienist through the AIHA Consultants Directory, the BGC list of Certified Industrial Hygienists.
Pro Tip:
Find one who is independent from the insurance company so results are unbiased.
Remediation options
1. Dig/Scrape
This is the most fail-safe way to deal with soil contamination. It involves hiring a contractor to come in and remove the contaminated soil, then dispose of it in a hazardous disposal location.
Cost: $$$
Maintenance: None
Speed: Fast
CAUTION:
This requires specialized hazardous materials licensing, and the contaminated soil must be disposed of correctly.
2. Bioremediation
Nature-based remediation, aka plants, funghi and/or microbes used to clean the soil in place.
This is a specialized methodology that must be performed by an experienced professional and is not recommended for higher contamination levels.
All plants involved must be tested and handled properly, and your lot must be retested after completion.
The duration of this process depends on contamination levels and types, but the study that shows the efficacy of this methodology was performed on contaminated industrial sites and lasted 12 months, which is the typical duration for this method.
The area undergoing remediation will be off limits during that period, but it can be performed at the same time as construction as long as the areas don’t overlap.
NOTE: This methodology is considered an “emerging technology” in post-fire remediation. There is not yet peer-reviewed data on post-fire bioremediation success.
Cost: $$
Maintenance: None once complete
Speed: Slow
CAUTION:
The risks of not working with an experienced bioremediation professional can include:
The process needing to be repeated,
Results may not be considered valid by authorities,
Accidentally exposing yourself and neighbors to contaminants.
An option:
The Center for Applied Ecological Remediation is an LA Local Nonprofit organization that performs bio-remediation and research.
They are led by Dr. Danielle Stevenson, pH.D in Environmental Toxicology, who has 15 years of experience in remediation, and performed the study referenced above.
You can reach out to them for a consultation here.
3. permanent cover
If your contamination is in an area that will be covered by a permanent structure, like the foundation of a building, a professional may advise that covering it is sufficient.
This is a recommendation that should only be issued by a Certified Industrial Hygienist.
TIP:
Be sure to get this recommendation in writing for your own liability purposes.
covering it with soil or mulch
is only a temporary stopgap
If you are not able to remediate immediately, it’s recommended that you cover over the contaminated are with at least 4-8 inches of fresh soil to prevent it from resuspending or traveling.
Please note:
This is not a remediation method, but a temporary cover as you assess options. Heat can cause contaminants to rise to the surface, and corrosion or digging can re-expose contaminants.
“How Much Does
Remediation
Cost?”
Remediation costs vary depending on the size of your lot, the level of contamination, and the remediation method you choose.
Some survivors have been able to include remediation expenses in lawsuits.
What Your
Neighbors Do
Matters… A Lot.
If your neighbors don’t remediate toxic soil, contaminants can spread onto your property through:
Rainwater runoff – Water flows downhill, carrying fine, contaminated particles with it.
Wind - Dry, dusty soil can blow across property lines.
Shared landscaping or drainage - Especially if you have adjoining yards, irrigation, or a natural slope.
Want to reach
your neighbors?
Some Labs
That Perform Testing
in LA County
MACS Lab Inc - (833) 522-6227
LATesting - (800) 303-0047
Torrent Laboratory, Inc - (408) 263-5258
Find LA City’s list of Environmental Consultants here.
*PostFire does not endorse or receive a listing fee from any of these labs. Hire and proceed at your own discretion.
This guide was built from the work of:
CAP.LA
Cap.LA is funded by R&S Kayne Foundation, with researchers from UCLA, Loyola Marymount, and Purdue.
1,600+ team-led tests in post-fire LA
Examining over a dozen heavy metals
Both burn scars
Dr. Danielle Stevenson
USC CLEAN
5,000+ self-collected tests in post-fire LA
Examining lead found in soils
Both burn scars
Dr. Andrew Whelton and Eric Bollens
Purdue University
After a Wildfire: Considerations for Building Environmental Testing
LA Fire HEALTH Study
Includes researchers from Harvard, Yale, UCLA, UC Irvine, UT Austin, University of South Carolina, Stanford, UC Davis, Chapman, and others.
Eaton fire residents united
Community advocacy group