when a historic neighborhood burns, who tests the soil for lead?

A public health official asked the question this month. Here is the honest answer, with the receipts.

the short answer

There is no standing program in the United States that automatically tests for lead after a large urban fire. Not for the children downwind. Not for the soil on the homes that did not burn. It gets improvised, every single time, by whoever is willing to fight for it after the smoke clears. Sometimes the fight is lost. After the January 2025 fires in Los Angeles, the federal government decided not to test the soil at all, which broke about twenty years of its own practice in California.

The system does not catch this. People catch it, one neighborhood at a time, usually too late, and only if someone insists.

why fire turns an old house into lead dust

A forest fire burns wood. A fire in a dense historic neighborhood burns lead. Houses built before 1978 are coated in lead paint, plumbed with lead solder, and full of older painted material. When they burn, the lead does not disappear. It goes up as fine particle and comes back down as fallout, settling into the topsoil of yards for blocks around, including yards whose houses never caught fire.

After the Eaton Fire, air monitoring near the burn measured a spike in atmospheric lead on the order of a hundred times background. That lead had to land somewhere. It landed on the gardens and play areas of families who thought they were safe because their house was still standing. This is the part the standard wildfire debris playbook was never built for, and it is exactly what Dr. Roe was asking about.

what a real response looked like, and what was missing from it

The Eaton and Palisades fires burned from January 7 to 31, 2025. Over ninety percent of Altadena's housing predates 1975. Here is what testing found, and who did it.

10 / 23

Sampling grids with intact, unburned homes downwind of the Eaton Fire that exceeded California's 80 mg/kg residential screening level for lead. Averages ran 80 to 167 mg/kg. The county attributed it to burned pre-1979 lead paint. (LA County Public Health, Roux sampling Feb, Mar 2025.)

~40%

Share of Altadena-area homes over the 80 mg/kg lead threshold in free testing of more than a thousand properties run by a UCLA team and a community project, because the official program could not reach everyone fast enough.

$0

Federal dollars spent confirming the soil was clean after debris removal. FEMA and the Army Corps scraped six inches and left, with no confirmation testing, breaking roughly two decades of California precedent. Seven members of Congress called it unacceptable.

The gap got filled by hand. LA County Public Health stood up a free soil-testing program, put up to three million dollars behind it, and opened free blood-lead testing for residents through its 1-800-LA-4-LEAD line. UCLA and USC ran free soil testing for anyone who asked. A Harvard-led study began tracking long-term exposure. Only after political pressure did EPA announce, in January 2026, its own voluntary soil-sampling effort. And California legislators introduced AB 1642, which would, for the first time, require the state to pre-write the rules for testing and cleaning contaminated soil after a fire instead of arguing about it mid-disaster. As of now it is a bill, not a law.

and louisiana?

Dr. Roe also named Louisiana. We could not find a single named building fire there with an organized lead response, and we will not invent one. What Louisiana has is the better-documented version of the same wound: New Orleans is one of the most lead-contaminated urban soils in the country, from a century of leaded paint, leaded gasoline, and contaminated fill. A 2025 to 2026 investigation found that more than half of the city's surveyed park playgrounds exceeded the federal urban soil-lead hazard level. Tulane researchers have mapped that soil for decades.

It belongs in the answer for one reason. The decades of New Orleans soil-lead mapping are themselves a model for what proactive looks like. You do not have to wait for a fire to know which ground is poisoned. You can measure it first.

so is anyone doing this on purpose?

No. Not as a standing, pre-positioned program that triggers on its own. Every response on the record (the 2018 Camp Fire, Ventura County, Los Angeles in 2025) was built after the disaster, by people who refused to let it slide, and Los Angeles shows the response can even go backward. But three of those efforts are worth copying, and a state committee can point to them by name.

1. The Camp Fire / Ventura County model: test, then test again

After the 2018 Camp Fire, Butte County soil-tested roughly 12,500 properties and found more than 4,000 still contaminated after the first six-inch scrape. Crews returned, in some cases up to five times, until each lot tested clean. Ventura County made post-fire confirmation soil testing a standing requirement after its own fires. This is the iterative test-and-reclear standard the federal government dropped in 2025. A jurisdiction can adopt it in writing before a fire, not after.

2. AB 1642: write the rules before the fire

California's pending Wildfire Environmental Safety and Testing Act would force a state agency to set, in advance, the standards for investigating and removing contaminated residential soil after a fire. It is the cleanest legislative template in the country for turning an ad hoc fight into a standing obligation. It is copyable now even though it is not yet law.

3. The LA County package, paired with a standing screening program

Free soil testing inside and downwind of the burn, free blood-lead testing for residents, funded remediation partnerships, and university and community labs as overflow capacity, all run through a health department's existing Childhood Lead Poisoning Prevention Program for pediatric follow-up. CLPPP already exists in most states. It is not fire-specific, but it is the channel a committee already controls.

if you live downwind of a fire and nobody has called you

You do not have to wait for a program that may never come. The most exposed people after every one of these fires were the families whose houses survived and who were told nothing.

  1. Get your children's blood lead tested. It is a simple, cheap blood draw. Ask your pediatrician or your county health department. There is no safe level; the CDC reference value is 3.5 µg/dL, and any result deserves a conversation.
  2. Get your soil tested before you garden or let kids play in the dirt. University and county labs ran free post-fire soil-lead testing after the LA fires. Ask your local health department and nearest university extension what is available where you are.
  3. Treat the dust and the painted objects inside as part of the same hazard. Fire-driven lead settles indoors too, and the older painted things in an old house (the dishware, the toys, the trim) are their own exposure path. That part you can check yourself, today, without waiting on anyone.
  4. Keep your own record. Date your results. The official program, if it ever arrives, will not have tested when the fallout was freshest. You will.

We built DetectLead because the honest answer to "who is testing this?" is almost always "no one is, yet." That is not a reason to wait. It is the reason to look.

sources

Compiled by DetectLead, May 2026, in response to a question posted to the National Center for Healthy Housing's Leadnet list. Numbers are stated as their sources state them; where a figure was reported only secondhand, we left it out rather than dress it up.

DetectLead is an independent lead-prevention resource. Questions, corrections, or a program we missed: eric@fluorospect.com · 631-461-1838