When wildfire smoke colors the sky a hazy shade of orange, it’s obvious that air quality might not be at its best.
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But there are other days when the sun is shining, the sky is blue and an “air quality alert” gets issued for your community. Is that really a watch-your-health warning you need to pay attention to?
The answer is yes, says pulmonologist Neha Solanki, MD — and here’s why.
What is an air quality alert?
Air isn’t just filled with … well, air. Pollutants are in the mix, too. Unhealthy gasses and particulate matter float all around us. These contaminants essentially dirty the air that we breathe as we go about our day-to-day activities.
The cleanliness of our air is in a constant state of flux, too. Air quality can quickly jump from good to bad or bad to good, depending on changing conditions. (More on that in a bit.)
“When air quality is bad it can become harmful,” warns Dr. Solanki. “You’re breathing in all of these toxic materials, all of this garbage in the air, and that can have a real effect on how you feel.”
So, how do you know when the air isn’t at its best? That’s where it pays to pay attention to the U.S. Air Quality Index (AQI), a nifty pollution scorecard kept by the U.S. Environmental Protection Agency (EPA).
More than 4,000 monitoring stations across the United States measure concentrations of five main pollutants. The watch list includes:
- Ground-level ozone.
- Particulate matter.
- Carbon monoxide.
- Sulfur dioxide.
- Nitrogen dioxide.
An air quality alert is triggered when a measured pollutant reaches unhealthy levels.
What do Air Quality Index levels mean?
The AQI basically scores air quality on a scale of 0 to 500, with lower numbers being better. To put the numbers in context, the EPA categorizes them in the following six levels (arranged by value):
- 0 to 50 – Good: Air quality is satisfactory. Air pollution poses little or no risk.
- 51 to 100 – Moderate: Air quality is acceptable. However, some pollutants may pose a moderate health concern for those who are unusually sensitive to air pollution.
- 101 to 150 – Unhealthy for Sensitive Groups: Members of sensitive groups (with existing respiratory conditions) may experience health effects. Most others are not likely to be affected.
- 151 to 200 – Unhealthy: Everyone may begin to experience health effects. Members of sensitive groups may see more serious health effects.
- 201 to 300 – Very Unhealthy: This triggers a health alert. Everyone may see more serious health effects.
- 301 to 500 – Hazardous: This triggers a health warning of emergency conditions. The entire population is more likely affected.
The rating reflects the pollutant measuring at the highest level at any given time, notes Dr. Solanki. So, if the ozone value is 175, the EPA rates the air quality as “unhealthy” even if other pollutants are at lower levels.
What causes poor air quality?
Many factors driving air pollution come from human activity. Cars, trucks and planes that burn fossil fuels emit nitrogen oxides into the air that contribute to the smog clouding many metropolitan areas.
Industrial manufacturing facilities and power-generating plants can spew out a high volume of pollutants, says Dr. Solanki. Even farms can pose a threat to air quality.
On a smaller scale, just using items such as gas stoves and candles add impurities to the air.
But it’s not just people. Mother Nature also contributes to air issues.
Wildfires send massive amounts of particulates into the air — and those pollutants can travel thousands of miles and across continents while riding the wind. (The same is true for volcanic ash sent skyward during eruptions.)
Weather impacts air quality, too, with sunshine, temperatures and wind all playing roles.
Health effects of poor air quality
As you probably suspect, poor air quality can make breathing-related conditions much worse. This includes conditions such as:
Polluted air also can cause shortness of breath and coughing in people who don’t have any underlying conditions. “Your airways react to these toxins and get angry and inflamed,” explains Dr. Solanki. “It can happen to anyone.”
But breathing in pollutants doesn’t just affect your lungs and breathing. Dirty air also has been linked to an increased risk for heart attacks, arrhythmia (irregular heartbeat) and strokes, plus just a general feeling of ickiness.
“The air you breathe in supplies, your blood, which supplies all of your organs — including your brain and your heart,” says Dr. Solanki. “If that air you breathe in is unhealthy, then your organs are getting exposed to toxic particles. It makes sense that you might feel unwell.”
What to do when air quality is bad
If there’s an air quality alert in your area, there are ways to minimize your exposure. Dr. Solanki recommends:
- Staying indoors as much as possible. Keep the windows closed and try to avoid going in or out too much. “Just opening the door for a bit will introduce polluted air,” cautions Dr. Solanki. (Follow these tips to reduce indoor pollution, too.)
- Turning on the air conditioning. This applies to your house and vehicle. And when you’re in the car, make sure to have the inside air recirculating rather than drawing in outside air.
- Using a HEPA (high-efficiency particulate air) filter in your home. A HEPA filter can trap both particulate matter and allergens. Dr. Solanki advises against using other types of home “air purifiers,” which can create ozone and make indoor air quality worse.
- Avoiding exercising outdoors. Keep your workout indoors, if possible. If you do take your workout outside, avoid times of day when pollution is high (such as during rush hour) and exercise in parks or other green spaces rather than along congested streets.
- Wearing a mask. If you absolutely have to be outdoors when the air quality is poor, wearing an N95 mask can help keep particulates out of your airways.
It’s often easy to dismiss air quality warnings — especially on those sunny days when you can’t see the pollution, notes Dr. Solanki.
But threats to your breathing aren’t always as obvious as a haze of wildfire smoke. Breathing in high levels of pollutants can cause health problems for your lungs, heart and elsewhere in your body.
“I do think people are paying more attention to air quality given recent events — and that’s a good thing,” says Dr. Solanki.