Wildfires Are Getting Worse, and So Is the Deadly Smoke They Bring With Them

Yves here. This article points out, which I must confess had not occurred to me, that the impact of wildfires on health can vary by region due to existing pollutants. And I don’t mean the obvious stuff like the smoke from the World Trade Center fires being particularly toxic by virtue of the amount of things like computers, drywall, flooring, and curtains that were torched.

And expect to see a new health protection hierarchy emerge: people who can obtain the better masks versus not….

By Yvette Cabrera, senior staff writer, environmental justice at Grist. Originally published at Grist

Last month, as a wildfire roared through the foothills above Santa Barbara, California, disaster-weary residents knew the drill and prepared for the worst. Some evacuated, while others sheltered in place, tracking news reports on wind patterns and the progress of firefighters battling the blaze known as the Cave Fire.

By the second day, the Santa Barbara County Public Health Department and the county’s Air Pollution Control District had issued an air-quality warning, and local libraries and nonprofits urged residents to protect themselves from the harmful smoke and ash, offering free N95 respirator masks. Yet most residents rushing through crammed grocery store parking lots and streets during the pre-Thanksgiving rush weren’t heeding the warnings to wear the masks.

As changing weather patterns driven by global warming have extended California’s wildfire season and increased the intensity and size of the infernos burning across the state, residents who don’t take precautions do so at their own peril. New research is revealing the lasting effects of exposure to the tiny particulate matter in smoke — which includes soot, dust, and even lead that fires might be re-releasing into the atmosphere.

According to Emily Williams, a Ph.D. candidate at the University of California, Santa Barbara, who specializes in climate science, social science, policy and the law, the climate change effects that California has experienced so far are just the tip of what’s to come. She’s compiled a fact sheet with Leah Stokes, a UCSB political science professor, to help citizens and the news media connect the dots between climate change and wildfires. The statistics they quote are eye-opening: Researchers found, for example, that in the American West, “climate change has increased the risk of fire weather fivefold and has doubled how much land has burned.”

“If you look at projections, with the rate that we’re going, these fires are peanuts,” Williams said. “They’re nothing compared to the sort of infernos that we can have.”

That increase in wildfires is concerning for Mary Prunicki, an asthma researcher at Stanford University who is studying the long-term health effects of wildfire pollution on people in the Bay Area. Earlier this year, Prunicki and her colleague Kari Nadeau released the findings from a study examining the health impact of pollutants from wildfires versus controlled fires. Their findings suggest that wildfires are more detrimental to human health than controlled fires, which are planned and purposely set under certain weather conditions to help maintain the health of forests.

Smoke from the Santa Barbara County Cave Fire blows over the Santa Barbara Mission as a local resident wearing a mask tries to protect himself from the air pollutants shortly before Thanksgiving.
(photograph by Daniel A. Anderson)

A local resident wears a mask to try to protect himself from the air pollutants in the smoke from the Santa Barbara County Cave Fire as it blows over the Santa Barbara Mission. Daniel A. Anderson

Her current research will look at the individual components of wildfire particulate matter and assess the health effects of exposure to each. Particulate matter is made up of particles of smoke, soot and dust, as well as what Prunicki called “hitchhiker toxins,” such as lead. Particulate matter will vary based on the type of fire and what’s being burned, she explained. PM2.5 — meaning particles with a diameter less than 2.5 micrometers, a twentieth the width of a human hair — is especially dangerous because it can make its way into a person’s lungs and bloodstream.

“If lead or any other toxic hitchhiker is on that PM2.5 or comprises a majority of it,” Prunicki said, “that is now going to be circulated through your body.”

Lead can get into particulate matter when a fire burns forest trees or other plants that have taken it up after it was released into the air or deposited in the soil, usually as a result of decades-old car emissions or industrial processes.

A New Lead Crisis?

A decade ago, University of California, Santa Cruz Professor Russell Flegal, who specializes in environmental toxicology, and his graduate student Kingsley Odigie, were the first to confirm that fires were reintroducing lead into the atmosphere. Flegal’s mentor, Clair Patterson, had in the 1960s pioneered techniques to measure lead levels, and discovered that additives in gasoline had contributed significantly to the rise in atmospheric lead levels around the world. Leaded gasoline for automobiles was introduced in the 1920s. By mid-century, as the U.S. highway system expanded, more cars hit the roads, leading to massive amounts of leaded emissions. Those lead particles settled in soil throughout California, particularly in densely trafficked urban centers like Los Angeles, but also in relatively pristine environments such as Santa Barbara.

Concerned with the climate change models that predicted that forest fires would increase in severity and frequency, Flegal decided to research whether lead was going back into the atmosphere. Flegal and Odigie studied ash samples from Santa Barbara’s 2009 Jesusita Fire, which burned nearly 9,000 acres, and they confirmed in their 2011 study that small amounts of lead sequestered in vegetation had been remobilized into the environment. Their subsequent work on forest fires releasing captured lead back into the atmosphere in Los Angeles, Chile, Africa, and Australiaconfirmed the ir original findings.

Howard Mielke of Tulane University’s School of Medicine, one of the nation’s leading experts on lead soil contamination, told Grist that although he hasn’t seen any long-term studies examining the health effects of wildfires re-releasing lead, what’s known about how lead particles in surface soil are picked up by the wind indicates that this air is not safe to breathe.

“If you have any smoke in the air you have aerosols, and if you have aerosols from forest fires especially forest fires near cities, the forests have absorbed lead and that would be remobilized,” Mielke said.

Further research is needed to clarify what amount of lead is being aerosolized by wildfires, but it would be sensible to use a dust mask to avoid breathing that air, said Mielke, who praised the Flegal and Odigie work as “tremendous.”

When it comes to lead exposure, those most at risk are children because of the neurotoxic effects the metal has on the developing brain. But research has shown that a wider swath of the population is also vulnerable, Flegal noted, including women of child-bearing age and older people whose bones are losing calcium due to osteoporosis.

Legal Protection

Shielding the public from the pollutants released during wildfires can be challenging, especially when it comes to protecting populations who work outdoors — one of the groups most at risk for breathing wildfire smoke. In California, farmworkers comprise a significant segment of that workforce, with more than 250,000 migrant and seasonal farmworkers across the state, according to the state’s Employment Development Department website.

In an artichoke field outside of Camarillo, California, farmworkers labor without respiratory masks during the 2018 Woolsey Fire, which burned nearly 97,000 acres over the course of nearly two weeks. Courtesy of CAUSE

As the Central Coast Alliance United for a Sustainable Economy, or CAUSE, discovered during the 2017 Thomas Fire along the Central Coast, ensuring that workers are protected goes beyond simply raising awareness about the risks of smoke inhalation. The blaze was one of the largest in California history, and the flames raged for weeks, putting farmworkers in Ventura County, where the fire started, in a difficult position: They are often only paid, say, by the crate of strawberries or box artichokes, no matter the weather — so skipping work is not an option for most workers.

“There were thousands of workers out, still working in the fields, often without any kind of protective masks during the worst of the air quality,” said Lucas Zucker,

the policy and communications director at CAUSE, which advocates on behalf of immigrant, indigenous, and undocumented communities throughout Ventura and Santa Barbara counties.

A coalition of statewide organizations, including CAUSE lobbied for an emergency regulation that went into effect earlier this year. The regulation requires employers to distribute N95 respirator masks to workers exposed to wildfire smoke or when air-quality index-levels for PM2.5 particulate matter are designated as “unhealthy.” The N95 respirator is designed to filter and block at least 95 percent of airborne particles, according to the U.S. Food and Drug Administration.

CAUSE saw improvements in the fields during the 2019 wildfire season with the use of masks, but Zucker said issues remain. Enforcing the use of masks requires monitoring by the state, for example. And Zucker said he doesn’t see any evidence of enforcement in the fields. And despite awareness campaigns, farmworkers continue to work during fires without the masks.

“A lot of farmworkers are very used to working in very difficult dangerous conditions already — they’re exposed to dust and pesticides,” Zucker said. “So most farmworkers in our area will wear bandanas over their face to protect from that.”

Other issues like language barriers and fear of retaliation prevent workers from reporting violations tied to this regulation, he explained. But one of the primary reasons many workers are driven to work through wildfires is out of economic necessity.

The current regulation doesn’t require that employers send workers home when air quality is bad due to wildfires. It’s a gap groups like CAUSE are hoping the state can address by strengthening the law to require that employers provide paid time off, similar to sick days, when air quality is unhealthy.

“That would be, to us, the gold standard — because at end of day these kind of workplace safety protections are really only going to get us half of the way,” Zucker said. “They’re not going to work effectively unless on the other side you have an economic safety net for people.”

However, according to Stanford’s Prunicki, without more research on the hazards of wildfire smoke, there are no concrete recommendations backed up by data that experts can say are effective for protecting people. Luckily for Santa Barbara residents, the county Air Pollution Control District cancelled its air-quality warning on the third day of the fire as containment improved and rainy conditions helped wash away ash. But the agency warned residents that winds and car traffic could re-release ash into the air, creating pockets of unhealthy particle concentrations.

“One thing we like to say is: There is no safe distance from a wildfire because we know that the smoke can travel hundreds of miles, and in that smoke is that particulate matter that we want to avoid,” she explained.

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  1. PlutoniumKun

    Yes, its been known for some time that wildfires can mobilise other pollutants in the environment. When the EPA started their review assessment of the scientific knowledge about Dioxins in 1996 there were lots of claims by industry that dioxins are ‘natural’, because there were known to be spikes of dioxin emissions and deposition in urban areas after wildfires. But more detailed studies revealed that most of those dioxins were from industrial emissions which had been deposited over forest areas. When you add into the mix bioaccumulation of very persistent toxins like lead, dioxins, etc., then you potentially have a situation where wildfires continually stir historic emissions around the environment until they find some fat to lodge in, and eventually that means we (or a polar bear) will eat it.

    Wildfires are also becoming a huge issue in Asia and South America – in the former because of palm oil plantations, although it seems likely with the drying up of watercourses like the Mekong, climate change will exacerbate this. Its likely to also become a critical issue in Russia as the tundra dries out.

    I think it is likely that for most of the world population, air pollution from wildfires will become a huge killer and the hardest for everyone to avoid.

  2. Ignacio

    I wonder whether ventilation filtering systems in public commercial and administrative buildings work with higher and more diverse concentration of pollutants, not to mention that most residential buildings perform natural ventilation. Having all the windows closed means worse air quality inside. Many of those filters will have to be replaced.

  3. Tom Stone

    UC Davis is conducting a long term study of the Tubbs fire in which I am participating,
    More than 5,000 structures and everything in them burned, in some cases the heat was so intense it turned aluminum engine blocks into puddles.
    That’s what e breathed here for weeks, and N95 and N97 masks were not immediately available in quantity, it was two days before I obtained one and they were among highest priority items ( Along with bottled water) that I ferried to where they were needed in my pickup truck.
    I have permanent damage, smoke inhalation was a contributing factor to my landing in the ER last year with congestive heart failure, they kept me for a week…
    I’m an old fart who has been exposed to a variety of toxins over the years, this exposure is unlikely to be a causative factor in my Cancer, however the young who breathed this smoke are very likely to experience a heightened risk of Cancer, neurologic and reproductive problems.
    The long term expense is going to be staggering.
    Hundreds of thousands were exposed and the damage will be showing up for decades.neuro

  4. Wukchumni

    Limbs of trees or the whole enchilada fall all the time around here, a Blue Oak in the back 40 that died about 5 years ago broke off about 6 feet up within the past fortnight, and supplied 6 wheelbarrow loads of burn pile material and a similar amount of firewood for the house.

    Where the tree broke, the wood within was rotten and perhaps twice as strong as Balsa wood, the bark probably keeping things upright until the gravity of the matter went horizontal.

    We can do burn piles here most of the winter, and ideally you want to set fire to them just before rain is coming, in ally with Mother Nature, so as to beat down the smoke potential, not that it’s a big deal when a small amount is broadcast in a large area.

    Hazard Reduction Burning Declaration for San Joaquin Valley


    The state is spending a tremendous amount of money reacting to wildfires, but expending not enough effort in creating precautionary scenarios for future forests in peril of perishing, and we can do it on the cheap compared to paying the piper in the heat of the moment.

    1. The Rev Kev

      Wish we could do fires here to burn off any number of old tree limbs and the like but we are still under total fire ban conditions. Start a fire here and you can expect a penalty of over $3,000 for a start. Our experienced firefighters have said that over the years the fires are hotter, the conditions are dryer and the season is going on longer and it is all due to climate change. And it is going to be getting a lot worse.
      From my back verandah I can see fires burning in the distant mountains and tonight you could see the fire front. Since this article is about mostly California, perhaps the Governor should note how our leadership is dealing with these fires. So next summer when California is burning and smoke is choking Los Angeles and San Francisco, he should do what our P.M just did – grab his family and jump on a plane to Hawaii for those lovely fresh tropical breezes.

      1. John Wright

        Depending on prevailing winds and topography, the range of the bad air in some of these wildfires is tremendous.

        During the Camp fire in Paradise, CA (2018), I hiked in the Point Reyes National Seashore in Marin County on the California Coast.

        The air quality was still somewhat poor, even 100+ air miles away.

        1. Wukchumni

          We were about 30 miles as the crow flies away from the 151k acre Rough Fire and once it lit, air quality went to shit for the rest of the summer, no hiking for me from then on into the fall, it was as if somebody turned off a switch.

          Every day from our perch far away, we’d watch a 12-14k foot huge mushroom cloud form far away in the heat of the battle, only to fall like a collapsed souffle once Sun set, rising again the following day.

  5. coboarts

    Growing up in San Diego’s east county, I was schooled early on about the dangers of poison oak being part of the smoke from fires. Breathing that… just bad. The wind patterns where I live have largely, so far, kept us fairly lucky, but my friends not so lucky complained about breathing difficulties, headaches, and I could see that the constant exposure, with no where to go to escape (unless you left the region completely), was creating a lot of stress.

    Last year, the notion was being kicked around in the Bay Area Council committees, about getting the state to cull the dead trees throughout CA to turn into pellets and sell to China (well, somebody would sell it). I haven’t seen it make any progress, but I haven’t investigated. It probably makes too much sense.

    1. RWood

      We have known for a long time that smoke from wildfires can be harmful to humans, but in recent years that knowledge base has increased significantly. And it may have reached a new level with research conducted by fire ecologist Leda Kobziar. After learning that some snow machines use bacteria as condensation nuclei, she started to wonder if bacteria was a component of smoke. Using petri dishes and drones she collected air and smoke samples at a prescribed fire.

      Turns out a surprising amount and diversity of bacterial cells and fungal spores gets lofted into wildfire smoke during a fire. The more severe the burn, the more cells it transports. This is a newly emerging area of research, but Kobziar thinks these microbes have the potential to affect human health.

  6. lordkoos

    This really hits home for me… in the seven years since we moved to eastern WA, there have been fires that filled our valley with smoke for weeks at a time every summer, except for this year when we thankfully got a reprieve. Some of the fires are nearby, some are in Canada or even Siberia, but at times we get the smoke from all of them. 2015 was a really bad year for the smoke here and it left me with a cough and sore throat that lasted from August until December. Being a musician I work with singers and I know two young people whose voices were damaged, one was temporary but the other lost part of his upper register, perhaps permanently.

    We have masks but my usual strategy is to stay indoors as much as possible and run the air filter. Needless to say, this a real drag in the summer when you’d like to be outdoors as much as possible. If it continues to worsen, we’ll have to think seriously about relocating.

    One effect of climate change here has not only been the increase in temperatures year-round, but also a marked increase in inversions that trap pollution from freeway traffic, wood smoke from stoves, and in the summer, wildfires. We used to only get this type of weather pattern for a few weeks in February, now it happens at any time of the year. Having grown up here and then moving back after fifty years away, the changes are easy to notice. At least in this valley, I don’t think there are many climate change deniers, even though the rural county population is quite conservative.

  7. False Solace

    The firefighters working in these fires sometimes don’t have appropriate gear either. There are a bunch of reports on social media about the volunteers working on the Australian wildfires, and they are indeed mostly volunteers. It sounds like the funding levels are perilously low, they don’t have the gear they need, and the crews are exhausted. The government is warning them not to crowdfund gear — but why would all these crowdfunding requests exist if the funding were remotely adequate? Anyway, the reports are just ghastly and the volunteers are in many cases fighting for their own homes.

  8. Anon

    I live in this territory. These fires (Tea, Thomas, Cave, etc.) have all brought disastrous air quality. They’ve become a near annual occurrence and some local folks have full-on canister breathing masks. I’ve seen women wearing them downtown.

    Paper masks, like the one worn in the top photo are ubiquitous. (Speaking of that photo; it appears staged. Few people walk in that area near the rose garden. Maybe including the Spanish/Roman mash-up facade of the reconstructed SB Mission beneath the smoke stream overhead was essential composition.)

  9. Anthony G Stegman

    We all need not worry about future wildfires. If Trump is reelected most of our forested lands will be clearcut leaving little left to burn. I expect he and his advisers to use that as a selling point in granting huge timber concessions in our public forests.

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