Hey, it's Flora Lichtenen, and this is Science Friday. Today in the show, the toxic fallout of urban fires.

This time last year, Los Angeles was on fire. More than 16,000 homes and buildings burned to the ground.

Cars, batteries, solar panels, insulation, cleaning

supplies, all up in flames, releasing toxic chemicals into giant smoke plumes that wafted across

the city. A year later, scientists are trying to understand the fallout from this urban wildfire.

What chemicals were left behind, how to remediate them, and what threats they pose to our health. My next two

guests have been at the forefront of this research, and for one of them, this work is personal.

Dr. Francois-So is a geochemist at Caltech, and Dr. Eifeng Ju studies air quality and its health effects at UCLA.

Welcome to you both to Science Friday.

Thank you for having me.

Thank you.

I want to get into the toxicology in a second, but Francois, let's start with your personal story.

What happened in your neighborhood?

Yes. Well, our neighborhood was almost completely

burnt down. Our street, only the house that we used to live in, and another one didn't burn.

Everything around is just complete desolation. The house is so contaminated with heavy metals and

asbestos, and it's completely unliable and unsafe.

I mean, obviously, this is so personal, but you also made it professional. Why?

Well, we made it professional because we have the tools to make a difference and bring data

that was missing. I guess the first thing I did when I saw that the fire was happening is I looked up if there was any paper that we're discussing how much lead and heavy metals and contaminants will be transported and how far and what are the risks I wanted to understand.

But it turns out there is almost no literature on this kind of

urban mega fires. There are new kind of threats. There is very little that is being known.

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