With smoke from the Bobcat Fire continuing to billow into communities throughout Burbank and the rest of the San Fernando Valley, health experts are warning residents to limit their time spent outdoors.
The Bobcat Fire, which began in the Angeles National Forest on Sept. 6, burned more than 60,000 acres, with 15% containment, as of Friday morning. The wildfire, whose cause remains under investigation, previously prompted evacuation orders for parts of Arcadia and Sierra Madre. Evacuation warnings also have been issued for parts of Pasadena, Monrovia and Altadena.
The Burbank Fire Department sent four personnel and a battalion chief to assist in combating the fire, according to Mark Hatch of the BFD.
The U.S. Forest Service said the Bobcat Fire is not expected to be contained until the end of October, though that date could change.
While the fire itself is not currently threatening Burbank, plumes of smoke have caused a massive drop in air quality. As of Friday morning, the eastern San Fernando Valley had an air quality index of about 71, placing it in the “moderate” designation. However, the air quality was expected to worsen, and had been at “unhealthy” and “very unhealthy” levels earlier in the week.
“People need to be extremely cautious with going outside and concerned with how bad our air quality is right now,” said Dr. Reza Ronaghi, a pulmonologist at the David Geffen School of Medicine at UCLA, in a phone interview.
He explained that the particles of wildfire smoke are very small — about one-thirtieth the size of a strand of hair. Those particles, when inhaled, can embed themselves deep in the lungs and other areas of the body, causing irritation, burning in the back of the throat and shortness of breath.
Ronaghi added that most healthy adults likely won’t see any long-term effects due to being exposed to smoke for a couple of days, though short-term symptoms could appear after a few hours of exposure.
But Dr. Nader Kamangar, a pulmonologist at the UCLA Medical Center, also warned that long-term exposure to wildfire smoke can increase the risk of some diseases like bronchitis and pneumonia. He added that a recent study suggested that the lung function of people affected by wildfire smoke remained affected two years after they were exposed to it.
“So that prior understanding of smoke exposure, where we would say, ‘It’ll be bad and then you bounce back’ — that was the line that was really told to most people for years — that may not necessarily be true,” he said.
The primary threat, however, is to sensitive populations, including minors, adults older than 65, pregnant women, people with limited access to medical care and those who have pre-existing heart or lung conditions.
Ronaghi cautioned that even if residents don’t see or smell smoke, dangerous particles could be lingering in the air. He recommended checking air quality indicators — one is available at aqmd.gov — to ensure that it’s safe to be outdoors.
Until air quality returns to normal levels, there are some measures residents can employ to keep themselves as safe as possible.
The best course of action is to stay indoors, something many have already been doing to protect themselves from the COVID-19 pandemic. Ronaghi added that people should be careful to ensure their residences are well insulated. Windows should be kept closed and openings below doors should be minimized.
“Because these particles are so small,” he said, “even the tiniest openings can allow them to come inside.”
Kamangar also suggested that people get an air purifier or run an air conditioner with a MERV 13 filter.
Those who must go outdoors should wear a mask to prevent the spread of the coronavirus, though Ronaghi cautions that cloth masks aren’t effective in keeping out tiny smoke particles. The Centers for Disease Control and Prevention instead recommends respirators such as N95 masks, which can filter out those potentially harmful particles.
But many respirators are being used by health workers on the front line of the pandemic, potentially forcing others to seek alternative face coverings. Kamangar believes that surgical masks offer some protection against wildfire smoke.
People whose jobs require them to work outside should try to get access to N95s, he added, potentially reusing the masks for a few days each.
Though he believes most of those respirators should be reserved for medical personnel, Kamangar said N95s with an exhalation valve — which does not prevent the wearer from potentially spreading the coronavirus — should have the valve covered with tape or a surgical mask.
SMOKE, COVID-19 LINK UNCERTAIN
Many longtime California residents are no strangers to wildfires, but the coronavirus pandemic offers a unique and opaque element.
Ronaghi believes that for a healthy adult, exposure to wildfire smoke does not increase the risk of contracting COVID-19, though it may worsen the symptoms of someone who already has the virus.
But some have another view. The CDC warns that “wildfire smoke can irritate your lungs, cause inflammation, affect your immune system and make you more prone to lung infections, including SARS-CoV-2, the virus that [causes] COVID-19.”
A few early studies have also suggested that higher levels of air pollution are related to coronavirus severity. However, Kamangar points out that research on COVID-19 is still developing.
Though the relationship between COVID-19 and smoke exposure, if any, remains unclear, Ronaghi warns that their symptoms can appear similar, potentially confusing some people who find themselves with a new cough or sore throat. The CDC notes that symptoms like fever and body aches are not related to smoke exposure.
And if a worldwide pandemic and a nearby fire weren’t enough, Ronaghi also points out that a flu season is on the way. But there’s something people can do about that threat: Get vaccinated.
“Now we’re dealing with the fires, the flu and COVID-19, and so it’s really important for people to try to get their flu vaccines early this season so that we can take one of these factors away,” he said.