L.A. Is Coated in Ash
When my family returned to our home in Santa Monica last Sunday night, we breathed a sigh of relief. Our house was fine, and the air quality was in the “good” category. Schools would reopen the next day. But as we unpacked, I noticed what looked like salt-and-pepper snow delicately dancing over the street. Ash from the Palisades Fire, burning just five miles north of us, was descending all around, coating the car we had left behind. In the backyard, it gathered over the small patch of turf we played on and in small clusters all across the garden, where my kids had recently planted carrots.
The next morning, we walked to school, talking about the blue sky. My 8-year-old pointed out the piles of windblown ash by the curb. That day, the kids would stay inside so the school could clean the debris from the playground equipment and yard.
As I walked the four blocks back home, a city-owned street sweeper buzzed past. When the truck’s bristles hit the pockets of ash, they kicked up car-size clouds of dust, sending all the debris back into the air. I clutched my N95 mask tighter against my face, pulled down my sunglasses, and jogged away. I closed the door tightly behind me.
That night, a local bookstore and mediation space held a ceremony to “call in the rain for a land devastated by fire.” Rain would help keep more fires from starting, and it would also help wash the ash away. For now, we’re left to deal with it on our own, swabbing surfaces, clearing streets, wondering what we’re breathing in and what it will do to the waterways that absorb it.
On Tuesday, the debris was continuing to fall, so the school held a “walking-only” recess. When I saw gardeners arriving armed with leaf blowers, my heart sank. (Los Angeles County has temporarily banned their use because they throw up so much dust.) But no one knew exactly the right way to clean up the mess. One neighbor was vacuuming their steps with a Shop-Vac.
With smoke, the hazards are clear: You can see it and smell it, and get out of the way. Our phones have been vibrating with air-quality indexes, which measure pollution in the air, but not ash. With ash circling like toxic feathers, it’s hard to know what is safe. The residue from house fires contains far more toxins than that of brush fires. The PVC pipes, lithium-ion car batteries, plastic siding, flooring, and everything else that evaporated in the blazes launched a soup of chemicals—nickel, chromium, arsenic, mercury—into the air. Older homes can contain lead and asbestos. Until Wednesday, the day after walking-only recess, L.A. County had an ash advisory in place, which recommended staying inside and wearing a mask and goggles when leaving the house.
But our lives in Los Angeles are largely outside: This is a city that dines outdoors all year long, where winter temperatures hover in the 60s and surfers are in the water in January. With no rain in the forecast, how long will our lives be coated in a fine layer of toxic dust? Maybe a very long time: A webinar put on by California Communities Against Toxics warned that the amount of ash that the fires had generated would take years to excavate, and created public-health risks.
The prospect of continued exposure to airborne chemicals sounds ominous, but Thomas Borch, a professor of environmental and agricultural chemistry at Colorado State University, was more sanguine. After the 2021 Marshall Fire tore through towns in the foothills of the Rocky Mountains, Borch studied contaminants in the soil at houses near the fire. Some of the properties had elevated levels of heavy metals, but most were still below levels of concern. And although living among clouds of fine debris might feel apocalyptic, Borch told me that the wind could be helping to dilute the contamination in my neighborhood. “A lot of these ashes spread out over a much bigger area,” he said, which helps mitigate their health impacts.
Once ash and soot creep inside homes—through doors and windows, on shoes and clothes—“it’s a lot harder to actually get rid of,” he added. Cleaning can reinvigorate pollution inside the home, so it has to be done carefully. Borch advised that we vacuum with a HEPA filter and wet-mop surfaces to keep pollution from building up inside the house.
But the real questions regarding human health and ash are still open. Researchers have only recently started to investigate how the ash from structural fires differs from that of wildfires. In Los Angeles, Borch’s colleagues have set up 10 coffee-bag-size samplers around the fires (as close as they were allowed to go). They also plan to collect ash from within the burn areas and from windblown dust to compare the different toxins in smoke and ash, as well as their concentrations in the weeks and months following the fires.
If rain does arrive, it will wash out much of the debris, and the city will feel clear again. But that rain could also carry contaminants into streams, reservoirs used for drinking water, or the Pacific Ocean. Perhaps by then the wind will have blown most of the ash away, or in places, such as my neighborhood, outside of the fire’s direct path—we will have cleared the ash on our own. (Clearing ash in fire zones is a regulated process.) My family is still waiting to pull up the vegetables in our yard, but I’m no longer worried about bouncing balls and biking. We’ve been slowly wetting down our stone patio and stairs and trying to gently sweep up the ash, while making sure we’re protected by gloves, goggles, and masks. Half of the neighbors are wearing masks outside. We’re still swirling around like ash from the crisis, waiting for the rains to put everything back in place.