The Palisades and Eaton fires, along with others that have erupted across Los Angeles County – most recently, the Hughes and Sepulveda fires – have left residents shaken. As they come to terms with the devastation, many residents who lost their homes and businesses may find hope in rebuilding.
But as they start on the road back, experts warn all area residents not to lose sight of the lingering health risks.
On Jan. 14, the Los Angeles County Department of Public Health issued a windblown dust and ash advisory. Strong Santa Ana winds had the potential to spread ash from the first round of wildfires, affecting air quality across the county. Another warning was issued the following day for those starting to clean up and sift through rubble.
On Jan. 23, a smoke advisory was issued in the area around the Hughes fire and there was a new dust and ash warning throughout Los Angeles County.
With continued red flag warnings indicating heightened fire risk, and Santa Ana winds returning periodically, the danger may remain for an extended period. Health officials say the fire debris may contain asbestos, heavy metals, and other dangerous materials, posing significant health risks, particularly under these weather conditions.
“Exposure to fumes and particles from burning material is associated with an increased risk of emphysema, which is the change in the lungs that leads to COPD,” said , MD, PhD, a pulmonary and critical care doctor at UCLA Health. “This would be our biggest concern from long-term exposures.”
Duration of health risks
Health experts caution that the risks associated with wildfire smoke can persist for weeks to months, depending on weather conditions and continued exposure to ash and debris. While air quality index (AQI) devices may show "healthy" levels, experts warn that these readings could sometimes fail to reflect true air quality accurately.
“I agree the air quality index is not perfect,” said , MD, interim chief of medicine in the Division of Pulmonary, Critical Care, Sleep Medicine, Clinical Immunology and Allergy at the David Geffen School of Medicine at UCLA. “It doesn't pick up aromatic hydrocarbons, lead, copper, asbestosis, ash, and plastics.”
Increased risk with prolonged exposure
This exposure is especially concerning for those who are sifting through the rubble. He urges people to take extra precautions in the coming weeks.
"If you're going into that area, it's full of rubble, much of it consisting of very fine particulate matter,” Dr. Belperio said. “There's a lot of ash on the ground, and even without wind, just walking through or kicking things up can create dust-ups. These dust- ups can contain a significant concentration of fine particulate matter that can enter your airways, reach deep into the lungs, and cause inflammation. With enough exposure, even a healthy person may experience airway irritation, coughing, or bronchospasms.”
For homeowners and business owners on-site for days to weeks, prolonged exposure to wildfire smoke and debris can significantly increase health risks. Continuous exposure can lead to more severe respiratory issues and other health complications.
Ultimately, exposure to wildfire smoke can have health consequences that extend beyond short-term effects, potentially leading to serious, long-term risks.
Lung health
“Wildfire smoke increases the risk of developing lung cancer the same way that pollution does by increasing particulate matter 2.5, although wildfire smoke leads to much higher levels of particulate matter 2.5 than pollution,” said , MD, PhD, a thoracic oncologist at the UCLA Health Jonsson Comprehensive Cancer Center. “These are particles that are too small to see, and when inhaled, cause irritation and inflammation in the lungs.
“Much of what we know about the impact of smoke comes from studies of firefighters, and while we know there is sufficient evidence that there is increased risk of lung cancer in this group, there are several factors that can influence this risk – the level and length of exposure as well as other chemical exposures that are variable in fires, such as heavy metals, arsenic, petrol, and diesel,” she said.
The concern is greater for those with preexisting respiratory conditions. Dr. Buhr says these pollutants can trigger flare-ups or worsen chronic conditions and that effects may be worse for older adults, children, and people who are pregnant.
“Kids have smaller and still-growing lungs and that inflammation is more likely to cause longer-term problems,” Dr. Buhr said. “For people who are pregnant, the small particles may deposit in the placenta, and can increase the likelihood of problems for the fetus, including increased risk of asthma in childhood.”
Triggering other complications
Exposure to these pollutants can also pose risks such as sinus complications and eye surface injury to healthier populations.
“The upper airway and sinuses are negatively impacted by air pollution,” said, MD, associate professor-in-residence of otolaryngology-head and neck surgery, at the David Geffen School of Medicine at UCLA. “Wildfires produce particulate matter, which can penetrate small air sacs in the lungs and pass into the blood. The effects of ash and dust are being investigated. Population-based studies have shown that individuals who are chronically in areas of elevated air pollution including particulate matter 2.5 have higher rates of sinus infections and worse sinus symptoms.”
Dr. Beswick says the issue may extend beyond the airways due to air pollution. Tiny particles from smoke can travel into the lungs, passing through the air sacs before entering the bloodstream. From there, they can circulate throughout the body, potentially causing additional harm.
, MD, assistant professor in clinical ophthalmology at Jules Stein Eye Institute, says several patients came into the clinic shortly after the fires started with eye irritation possibly caused by smoke and ash exposure.
“The primary risk to eye health is ash or dust potentially landing in the eye or tear film, which could cause an abrasion on the surface of the eye, or even risk a corrosive injury,” Dr. Lu said. “A gritty, sandy sensation, eye irritation, eye redness and blurred vision could all be symptoms of potential eye injury.”
Steps to take care of your health
While the skies around Los Angeles may have largely cleared, it’s important to remember that much of the particulate matter posing health risks is invisible to the eye. That’s why experts suggest monitoring for symptoms as an important step in protecting your health.
“Things to look out for include an increase in cough or wheezing, chest tightness or burning sensation, lower exercise tolerance, coughing up an increased amount of phlegm, or feeling drowsier or more confused than normal,” Dr. Buhr said.
Dr. Buhr also recommends following the guide for protecting your health around wildfires.
And in the case you still have doubts about the air quality in your area, Dr. Belperio stresses a simple rule of thumb.
"If the air quality monitor near your location shows green, meaning the index is below 50, and you don’t smell smoke you're likely in good shape,” Dr. Belperio said. “However, keep in mind that some monitors may be far from your actual area, which can be an issue. But if you don't smell smoke or notice any odors, that's another good sign that the air quality is safe, as your nose sensors for ash are better than your sight and the AQI."
Multiple air quality monitors are helpful, including the .
