California Wildfires Spur Asbestos Concerns

Asbestos Exposure & Bans

Six major wildfires are torching Southern California, covering an area larger than New York City and Boston combined.

The Thomas Fire — the largest of the six and the fifth-largest blaze in modern California history — covers 238,500 acres. The other fires have destroyed nearly 260,000 acres, officials said.

At least 18,000 homes and other structures are threatened by the fires and more than 1,000 structures have been wiped out, according to the fire protection agency Cal Fire.

Cal Fire officials said the Thomas Fire was 30 percent contained as of late Wednesday.

Some residents have been allowed back in their homes following mandatory evacuations, but thousands of other families remain displaced.

Aside from the dangers of the blaze itself, Cal Fire and other government agencies are warning Californians about the dangers of asbestos and other toxins released by the fire.

The air quality conditions remain poor in much of Southern California. The smoke from the fires alone has forced many to evacuate their homes, including Dr. Charles Conway, a mesothelioma specialist and director of surgical oncology at Ridley-Tree Cancer Center in Santa Barbara.

“The smoke is terrible. My family and I wear masks,” Conway told “The visibility is also a big danger. We had to evacuate because of air quality. Others have to relocate in the hope of being safe, while still trying to be logistically able to get to work. People are trying to carry on as normally as possible.”

Another concern is improper cleanup of dust, soot and ash. Residents and business owners evaluating damage or rummaging through debris for valuables are at risk of dangerous asbestos exposure if the appropriate precautions are not taken.

“Inhaling smoke or dust that may contain asbestos is concerning, and people should be even more diligent about wearing masks and being cautious,” Conway said.

Fires Can Disturb Asbestos Materials

The Thomas Fire has raged in Southern California since Dec. 4, straddling Santa Barbara and Ventura counties.

Gusty Santa Ana winds have fueled the fire, along with the drought-parched terrain. The fire has left a path of destruction, reducing more than 700 single-family homes to rubble.

Fire and asbestos are a deadly combination. When houses burn, asbestos fibers from building materials may become airborne, creating a toxic situation. Inhaling or ingesting asbestos dust can lead to serious health conditions such as mesothelioma, a cancer that usually develops on the lining of the lungs or abdomen.

Asbestos fibers can travel large distances through smoke and wind, so while a specific home or business may not contain asbestos materials, the area can be contaminated from properties that do.

“I don’t think there is anyone who shouldn’t be wearing a mask at this point, given where the air quality is right now, how unhealthy it is,” Dr. Richard Belkin, a lung specialist, told “Everyone in the community should be wearing masks when they are outdoors.”

The County of Santa Barbara released a message to residents to take precaution when handling materials or debris left behind by the wildfires.

Recommendations include:

  • Using proper face masks. Health officials have handed out more than 200,000 free N95-rated face masks over the past week, according to The Tribune in San Luis Obispo. Dusk masks and surgical masks aren’t effective at filtering hazardous particles such as asbestos, officials with the Santa Barbara County Air Pollution Control District said. Using your hand, shirt or a scarf to shield your mouth and nose won’t work either. N95-rated masks are an affordable and effective option if fitted properly.
  • Using damp cloths and spraying areas lightly with water. Wetting down asbestos-containing materials is a common way to prevent fibers from becoming airborne. Officials urge to use the minimum amount of water to avoid overtaxing runoff systems.
  • Removing ash using vacuums with HEPA filters. Using a negative-pressure enclosure vacuum system with a high-efficiency particulate air (HEPA) filter keeps asbestos from becoming airborne. If you do not have access to these tools, it is best to leave cleanup to abatement professionals.
  • Avoiding any skin contact. Officials highly recommend wearing gloves, pants and long-sleeved shirts to avoid skin contact with the ash. Burning certain plastics such as PVC can release dioxins, a known human carcinogen that can penetrate the skin through smoke and dust. While asbestos fibers cannot penetrate the skin, they can attach to skin or clothes, potentially leading to secondhand exposure away from the cleanup site.

Additionally, health officials said anyone with heart or lung problems should not be involved with ash cleanup.

Asbestos Concerns from Wildfires Are Nothing New

The Thomas Fire currently ranks as the eighth most destructive wildfire in California history.

And while that ranking may rise until the fire is fully contained, the destruction likely won’t reach that of the Tubbs Fire, which ravaged Sonoma County in October.

Tubbs covered just 36,807 acres — a fraction of Thomas’ 238,500 acres — but destroyed nearly six times as many structures.

The more than 5,600 structures wiped out by Tubbs were nearly twice as many as the No. 2 ranked Tunnel Fire, which devastated Oakland Hills in Northern California 26 years earlier.

And Tubbs was just one of several fires that tore through Northern California in October, covering more than 245,000 total acres. After the fires were contained, the focus then turned to concern over cleanup efforts.

At least three counties declared a state of emergency over the hazardous waste from the fires.

“Just think of all the hazardous materials in your home,” Dr. Karen Relucio, chief public health officer in Napa County, told the New York Times. “Your chemicals, your pesticides, propane, gasoline, plastic and paint — it all burns down into the ash. It concentrates in the ash, and it’s toxic.”

The California Department of Toxic Substances Control is in charge of evaluating and removing the most hazardous debris at a cleanup site, including asbestos materials.

Older homes destroyed by the fires may contain asbestos siding, shingles or pipe insulation. Asbestos was a key ingredient in virtually every kind of construction material until 1979, when health concerns brought regulation of the toxic mineral.

“Overall, air quality is just as bad as the damage, if not worse, and it’s affecting more people than the actual fire itself,” Conway said. “And add in the fact of possible asbestos in it, and the pollution is all the more concerning.”

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