SACRAMENTO, Calif. _ Air quality related to fine particulate matter was expected to hit "unhealthy" or "very unhealthy" levels for the seventh time this year in the Sacramento region on Wednesday, more "code red" or worse days than any other year since at least 2009, according to the latest data from local air districts.
Wildfire smoke often produces high concentrations of PM2.5, very fine particulate matter that can harm the heart and lungs. Local air districts track the amount of PM2.5 in the region to create an Air Quality Index. An Air Quality index over 150 is considered unhealthy � a "code red" day. An Air Quality Index over 200 is considered very unhealthy.
Including Wednesday, there have been seven days in 2018 where the average, 24-hour Air Quality Index for PM2.5 hit unhealthy levels somewhere in the region.
Two of those days came in August when the Carr Fire raged in Shasta and Trinity Counties. The other five have come this month, including at least two days where average PM2.5 hit very unhealthy levels.
Air Quality officials predict unhealthy, code red days for Thursday and Friday, with some easing during the weekend.
"Fine particulate matter that you find in wildfire smoke is very unhealthy to breathe," said Lori Kobza, spokeswoman for the Sacramento Air Quality Management District. "Not only does it get into your lungs, it gets into your blood stream. It can trigger cardiac problems and other respiratory problems."
PM2.5 readings are often highest during wildfires, but can also rise in the winter because of smoke from wood burning stoves and fireplaces. PM2.5 is different from ozone, or smog, which often reaches peak levels in the summer.
Counties surrounding Sacramento are often more affected by wildfire smoke than Sacramento itself, Kobza said. The past few days have been unusual in that some of the worst PM2.5 readings have come from Sacramento County.
"We do have a high-pressure system � it is keeping everything locked in," Kobza said.
