Smoke and dust advisories are in effect as fires, including the massive Tick Fire, continue to burn across the greater Los Angeles region.
Poor air quality is expected Friday along the coast, in the San Fernando and Santa Clarita valleys and in the San Gabriel mountains. Wind-driven dust is also expected in Riverside and San Bernardino counties.
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If you notice smoke, dust or ash in the air, officials recommend that you stay inside and close your windows and doors.
Wildfire smoke is a mixture of small particles, water vapors and gases. Doctors say that fine particulate matter is the primary health concern.
CALIFORNIA FIRE MAP: Active fire reports, perimeters for SoCal fires
"So they can cause burning eyes, scratchy throat, runny nose, headache, shortness of death, chest pain, wheezing," said Dr. Marinelle Camilon with Dignity Health Northridge Hospital.
Camilon said since the Saddle Ridge Fire, she's seen a steady rise in people filling their asthma inhalers.
"We have some pretty high-risk people like children, elderly, pregnant ladies, they should not be going outside today," Camilon said.
PHOTOS: Tick Fire in Santa Clarita
Camilon said nasal sprays may help. Also, she says if you have lung disease, you should take your medications and use your inhaler if you need it.
"I would recommend trying to stay out of the area if you can, and again, if they feel symptoms that's worrisome for them, if they're having any chest pain or shortness of breath, to see a medical professional right away," she said.
Camilon said smoke can last several days after the fire is out.
Click here to see the latest on the multiple fires burning across the region.
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Tick Fire air quality: Smoke, dust advisories in effect as fires burn across Southland