PORTLAND, Ore. -- On Tuesday, many people woke up to wildfire ash covering their cars in Portland. A strange sight for a city hundreds of miles from the nearest fires.

Dr. Richard Leman with the Oregon Health Authority says that's actually not the dangerous part.

"The ash we're pretty good at filtering out, our bodies are built for that. The problem is sometimes you get these really fine particles, and they're so fine they can get taken down into the lungs, they can even get into the bloodstream," he said.

Lehman cautioned against exercising outside unless you have to, and ask if your child's sports practice can go indoors until smoke levels decrease. He said those smoke particles can increase the chances of a heart attack if you have heart disease or lung problems.

Kids are especially vulnerable.

"Little kids have tiny airways and if those tiny airways get irritated and swollen a bit, not as much air can move through so it can make for more coughing and trouble breathing," he said.

The Portland metro area's air quality was downgraded to unhealthy Tuesday morning and remained unhealthy throughout the day.

The Air Quality Index (AQI) was 168 on Tuesday morning and 160 in the afternoon. A rating higher than 150 is considered unhealthy for everyone. AQI measures how many particles are in the air.

The Environmental Protection Agency says people should reduce prolonged or heavy exertion, and consider staying inside. People with heart or lung disease, older adults and children are at higher risk of health effects and should avoid prolonged or heavy exertion.

The poor air quality was a result of wildfires burning in Oregon currently, especially the Chetco Bar Fire in southern Oregon and the Whitewater Fire near Mount Jefferson.

Current air conditions

The smoke cleared from the area by Tuesday evening.

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