Shawn Vestal: Smoke gets in your eyes, and throat, and lungs, and heart…

Breathing all this smoke is similar, in some ways, to contracting a virus.

Wildfire smoke is composed of a complicated mix of gases and small particles that can vary from fire to fire, depending on what’s burning. The tiniest bits – particulate matter of 2.5 microns in diameter or less – can make their way deep into our lungs, where our bodies respond as if we had contracted an infection.

That’s how environmental health scientist Sarah Henderson of the University of British Columbia put it to National Geographic in a recent piece on the health effects of wildfire smoke.

When these tiny particles stick in our lungs, our body’s immune response kicks in – but then it keeps kicking past the point of usefulness. Unlike a virus, we can’t break down particulate matter in our lungs, so the result is long-lasting inflammation, which is associated with a host of other health problems.

In addition to the lungs, that inflammation can affect the kidneys, liver and possibly even the brain, Henderson said – which has the potential to worsen conditions such as asthma or COPD, and may affect the unborn children of pregnant women who breathe the smoke.

We know it’s not good. Our eyes and our throats tell us that. But what we don’t know is how bad and how long-term these problems may be, in part because we’ve never breathed this much wildfire smoke at one time before.

We’re guinea pigs on the question, midexperiment. But there are reasons to believe that long-term smoke exposure could have long-term effects even after the skies clear.

Our air quality was atrocious this week, of course. It’s a sign of the season that breathing that terrible air – but still having our homes and families – makes us the lucky ones, but that it’s a mixed kind of good fortune. Starting Sunday, we’ve breathed the most polluted air, by far, any of us have experienced since we began measuring small-particle air quality in 1999.

Before Sunday, our highest Air Quality Index was 257, and that was the highest by a large degree. One hundred and above is considered unhealthy for some; 300 and above is considered hazardous.

Starting Sunday, our 24-hour averages went: 368, 479, 406, 315, 215.

Thursday, we began to head into the merely “unhealthy” realm of 166.

Air quality was awful in California and Oregon, too, of course, and elsewhere around the West to a lesser degree.

This threatens to become more common as the climate warms and wildfires worsen. In the early 2000s, we had far fewer days of air quality that were worse than “moderate” on the AQI, and when we did, it was usually a result of wood stove smoke during winter inversions. We went years without a single day of bad air quality.

That pattern began to change in 2015, when we had 12 August days of the smokiest skies we’d experienced to that point. And it’s worsened steadily since: Of the 86 days of poor air quality since 1999, 56 have come since 2015 – worsening as we go. Before that, our bad air days were almost entirely related to wood smoke and winter inversions; since 2015, it’s virtually all wildfire.

It’s no surprise that this air is bad for us. The Spokane Regional Clean Air Agency notes that small-particle pollution has been associated with a wide range of health problems, including premature death in people with heart and lung disease; heart attacks and other heart problems; aggravated asthma and other respiratory problems.

All that is based on what we know from past experience, though. And past experience tells us little about the kinds of long-term exposure to wildfire smoke that we’re seeing now.

There’s reason for concern, though. The EPA reports that PM 2.5 particles can not only trigger extended immune responses resulting in inflammation that cuts off oxygen supplies for those most affected but may also be able to enter the bloodstream itself. That means potential inflammatory effects in the heart, brain and other organs.

A 2018 study in the Journal of the American Heart Association found an association between the wildfire smoke in California’s 2015 fire season and problems with blood flow to the brain in emergency room visits. A Lancet study the following year linked heart disease with living in cities with high levels of air pollution.

Heart attacks and irregular heart rhythms have also been linked to wildfire smoke, National Geographic reported. And there is a possible ripple effect from inflammation; if our immune systems are inflamed to deal with smoke, their ability is weakened for dealing with other problems.

Like COVID-19. The CDC says that breathing a lot of wildfire smoke can make you more susceptible to COVID-19. And having COVID-19 can make you more susceptible to suffering wildfire-related heart and lung problems, the CDC says.

We still have a lot to learn. Unfortunately, we’re very likely to have a lot of educational opportunities in the future.