Los Angeles is now a week removed from the day that multiple devastating wildfires erupted to torch tens of thousands of acres. But still, the question remains if people should wear masks to limit their exposure to toxins in the air.

Calculating air pollution from wildfires and other events has become more complicated. That doesn’t mean it’s necessarily more accurate.

Already known for having some of the worst air quality in the U.S., people in Southern California are now also at risk of inhaling smoke.

Wildfire ash carries many carcinogens that could cause short- and long-term health problems, including asthma attacks and difficulty breathing.

A wildfire smoke advisory remains in effect this weekend for most of Southern California due to wildfires in Los Angeles County.