Photos: This is how bad the air in Chicago is right now
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The Windy City was enveloped in smoke Thursday as air pollution from over 800 Canadian wildfires wafted through the city and suburbs.
The air contained hazardous levels of PM2.5, a particulate matter that can lodge in the lungs and cause adverse health effects, especially in immunocomprised people and those with respiratory conditions.
Some Chicagoans masked up while others spent a hazy morning swimming in Lake Michigan.
Chicago Sun-Times photojournalists were on the ground to document the city grappling with the in-your-face pollution.
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The Chicago Theatre sign is obscured by smoke from the wildfires in Canada on Thursday.
Pat Nabong/Sun-Times
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Pedestrians wearing masks cross a street in the Loop to protect themselves from wildfire smoke coming from Canada on Thursday.
Pat Nabong/Sun-Times
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A commuter wearing a mask waits for a bus Thursday on West 26th Street in Little Village as air quality drops.
Pat Nabong/Sun-Times
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North Avenue Beach is obscured by smoke from the wildfires in Canada on Thursday.
The poor air quality and high levels of airborne pollution led the city to close beaches along Lake Michigan.
Anthony Vazquez/Sun-Times
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A swimmer in Lake Michigan near Montrose Point Bird Sanctuary as air quality drops Thursday.
Pat Nabong/Sun-Times
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The Chicago Board of Trade building in the Loop is obscured by smoke from wildfires in Canada on Thursday.
Pat Nabong/Sun-Times
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A pedestrian crosses the street while covering her nose in the Loop as air quality drops Thursday.
Pat Nabong/Sun-Times
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Michigan Avenue buildings obscured by smoke from wildfires in Canada on Thursday,
Pat Nabong/Sun-Times
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Lincoln Park obscured by smoke from the wildfires in Canada on Thursday.
Anthony Vazquez/Sun-Times
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A commuter wears a mask while waiting in Greater Grand Crossing on Thursday, a day of poor air conditions across the greater Chicago area.
Candace Dane Chambers/Sun-Times
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Bronzeville is obscured by smoke from the wildfires in Canada on Thursday.
Candace Dane Chambers/Sun-Times
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A masked woman in Greater Grand Crossing on Thursday.
That neighborhood, like others across Chicago, was enveloped by smoke from the wildfires in Canada.
Candace Dane Chambers/Sun-Times
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Wildfire smoke covers the city as viewed from Lincoln Park on Thursday.
Anthony Vazquez/Sun-Times
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Buildings on Michigan Avenue are obscured by smoke from wildfires in Canada on Thursday.
Pat Nabong/Sun-Times
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Smoke in Grant Park from Canadian wildfires, causing air quality to drop across Chicago on Thursday.
Pat Nabong/Sun-Times