While it makes for spectacular sunsets, smoke from wildfires is a potential health hazard, especially for those who are older or have certain underlying health conditions.
In fact, smoke from Canadian wildfires that blew over the U.S. this spring and summer led to a spike in people with asthma visiting emergency rooms, particularly among those 5–17 and 18–64 years old, according to two studies published by the Centers for Disease Control and Prevention (CDC).
A national study, drawing data from 4,317 health facilities, found ER visits averaged 17 percent higher than normal on days when wildfire smoke pushed the air quality iIndex (AQI) above 101, a level categorized as “Unhealthy for Sensitive Groups.” A second study found an increase in asthma-associated emergency department visits across New York. It noted that on the worst AQI day (June 7), asthma-associated emergency department visits increased 81.9 percent statewide, excluding New York City. On that day, the Associated Press reported, the “New York City skyline could barely be seen across the Hudson River from New Jersey, while the Washington Monument and National Mall were enveloped in a rainless gray haze.”
The American Lung Association cautions that certain groups should monitor their breathing and exposure to wildfire smoke: those over age 65 or under age 18, those who work outdoors, and those who have asthma, COPD or other lung diseases, chronic heart disease or diabetes.
The color-coded AQI from the Environmental Protection Agency (EPA) measures how clean or polluted the air is, and what associated health effects might be of concern, especially for ground-level ozone and particle pollution. The EPA's website, AirNow.gov, allows users to enter a zip code to get an air quality forecast.
What do the AQI colors and numbers mean?
The EPA has developed the AQI to show harmful particle pollution on a scale of 0 to 500. Anything above 150 is considered unhealthy for everyone. The smoke from wildfires contains fine particles 2.5 micrometers in diameter and smaller.
Here’s how the EPA breaks it down by color:
Green. Good air quality — from 0 to 50 — when “it’s a great day to be active outdoors.”
Yellow. Moderate air quality — from 51 to 100 — when people who are unusually sensitive to particle pollution should consider shorter and less intense outdoor activities.