Smoke from the Robbers fire in the Placer County foothills has fouled the air around the Sacramento region, officials say.

The cities of Sacramento, Auburn, Elk Grove, Placerville and more received a rating of "unhealthy for sensitive groups" Friday, said Heather Kuklo, air quality specialist for the Placer County Air Pollution Control District.

Those ratings can change quickly, Kuklo said. "Smoke doesn't just stay in one place; it's dynamic, it can always move."

The smoke from wildfires contains small particles that are harmful to people, she said. These pollutants can enter the lungs and be hard to expel. "It can be especially troublesome for children, whose lungs are still growing, or the elderly," she said.

The recent heat wave adds to the problem, Kuklo said, putting even more stress on bodies trying to fight the effects of heavy smoke.

Despite the danger, Kuklo said Friday's conditions were a large improvement from Thursday, when air quality in the city of Auburn was rated "unhealthy" for all. Monitoring stations in Auburn on Friday showed fewer pollutants in the air, she said. Lower temperatures and downslope winds this weekend could aid in removing the smoke from Placer County, Kuklo said, but they could also bring more smoke down to Sacramento.

Fires in the mountains have been known to fill the Valley with noxious smoke, as in July 2008, when more than 300 fires were burning in the state.

For now, the best advice is to simply be cautious. "If you smell smoke, if you're irritated, please take it into consideration," Kuklo said. She suggested going to a movie or a mall instead of spending time outdoors. She added that coaches, parents, and day care employees should suspend children's outdoor activities if they can smell smoke.

Kuklo said some families and organizations have called the air pollution district seeking advice. She said the district can give recommendations, but the decision is left to the individual.

At least one organization decided to play it safe.

"Thursday we suspended all outdoor activities and closed both of our pools," said Patti Waskowiak, aquatics director for the Auburn Recreation District. Outdoor sports resumed and both pools reopened Friday.

Kuklo said the decrease in pollutants was a good sign. She said areas still under watch are Lincoln, Roseville, Auburn and Colfax. "This fire is still going; we have to be careful for now."

Air quality conditions can be checked online at www.sparetheair.com or www.AIRNow.gov.

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