All sense of survivors’ guilt was fleeting for those residents whose homes remained standing after wildfires ripped through the Los Angeles area three months ago.

Many worried that smoke from the Eaton wildfire that destroyed more than 9,000 structures and killed 18 people may have carried toxins, including lead, asbestos and heavy metals, into their homes.

But they struggled to convince their insurers to test their properties to ensure it was safe to return.

Nicole Maccalla, a data scientist, said embers burned more than half of her roof, several windows and eaves were damaged, and her house in Altadena was left filled with ash, debris, soot and damaged appliances.

She said her insurance adjuster said USAA would pay for contamination testing, but after choosing a company and coming back with the results, her claim was rejected.

The adjuster said the company only covered testing in homes with major damage.

“Every single item is a battle,” said Maccalla. “It’s denials and appeals and denials and appeals, and you wait weeks and weeks and weeks for responses.”

Crowdsourcing contamination data

Maccalla and others banded together as Eaton Fire Residents United, sharing indoor environmental testing data and compiling the results in an online map.

Of 81 homes tested so far for lead, all show elevated levels, according to the group. “I’ve already had multiple people reach out and say: ‘Thank you for publishing this map … because my insurance company has changed their mind and approved testing,’” said Maccalla, who helped design the data collection to verify results and maintain privacy.

Many homeowners paid privately for the testing after their insurance companies refused, revealing gaps in coverage.