![Canadian wildfire smoke was thick in the air over New York's Yankee Stadium on June 6, 2023. AP Photo/Frank Franklin II Wildfire smoke can harm human health, even when the fire is hundreds of miles away – a toxicologist explains why - information](https://media.cnn.com/api/v1/images/stellar/prod/230628115549-lincoln-memorial-smoke-haze-restricted-062723.jpg?c=original)
Photos: Canadian wildfires impact US air quality
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Hazardous air quality hit NYC as smoke moves from Canada wildfires
![Canadian wildfire smoke was thick in the air over New York's Yankee Stadium on June 6, 2023. AP Photo/Frank Franklin II Wildfire smoke can harm human health, even when the fire is hundreds of miles away – a toxicologist explains why - information](https://www.washingtonpost.com/resizer/cLj00bkRyV_17S2gIQF9OXQYsvE=/arc-anglerfish-washpost-prod-washpost/public/DIRGRO5J2JHQRNLQD2HFTDA7EE.jpg)
Hazardous air quality hit NYC as smoke moves from Canada wildfires
![Canadian wildfire smoke was thick in the air over New York's Yankee Stadium on June 6, 2023. AP Photo/Frank Franklin II Wildfire smoke can harm human health, even when the fire is hundreds of miles away – a toxicologist explains why - information](https://www.washingtonpost.com/resizer/7eujUtgsB61WVxYmJ-OqgeWpF-A=/arc-anglerfish-washpost-prod-washpost/public/PO2A2VTW7BB4LI6ETJMLEFEUEA.png)
Hazardous air quality hit NYC as smoke moves from Canada wildfires
![Canadian wildfire smoke was thick in the air over New York's Yankee Stadium on June 6, 2023. AP Photo/Frank Franklin II Wildfire smoke can harm human health, even when the fire is hundreds of miles away – a toxicologist explains why - information](https://media.cnn.com/api/v1/images/stellar/prod/230608131526-09-canada-smoke-in-us-gallery-update-0608.jpg?c=original)
Photos: Canadian wildfires impact US air quality
![Canadian wildfire smoke was thick in the air over New York's Yankee Stadium on June 6, 2023. AP Photo/Frank Franklin II Wildfire smoke can harm human health, even when the fire is hundreds of miles away – a toxicologist explains why - information](https://s3.amazonaws.com/arc-authors/washpost/b2ca5a9c-84e0-4fba-9ebe-126ad4f43947.png)
Hazardous air quality hit NYC as smoke moves from Canada wildfires
![Canadian wildfire smoke was thick in the air over New York's Yankee Stadium on June 6, 2023. AP Photo/Frank Franklin II Wildfire smoke can harm human health, even when the fire is hundreds of miles away – a toxicologist explains why - information](https://s3.amazonaws.com/arc-authors/washpost/b6e15c90-23e6-4c90-9a3a-bd6243f52e7e.png)
Hazardous air quality hit NYC as smoke moves from Canada wildfires
![Canadian wildfire smoke was thick in the air over New York's Yankee Stadium on June 6, 2023. AP Photo/Frank Franklin II Wildfire smoke can harm human health, even when the fire is hundreds of miles away – a toxicologist explains why - information](https://s3.amazonaws.com/arc-authors/washpost/8e879998-f43b-4d9a-bb68-000374970048.png)
Hazardous air quality hit NYC as smoke moves from Canada wildfires
![Canadian wildfire smoke was thick in the air over New York's Yankee Stadium on June 6, 2023. AP Photo/Frank Franklin II Wildfire smoke can harm human health, even when the fire is hundreds of miles away – a toxicologist explains why - information](https://media.cnn.com/api/v1/images/stellar/prod/230608203901-10-canada-smoke-in-us-gallery-update-0608.jpg?c=original)
Photos: Canadian wildfires impact US air quality
![Canadian wildfire smoke was thick in the air over New York's Yankee Stadium on June 6, 2023. AP Photo/Frank Franklin II Wildfire smoke can harm human health, even when the fire is hundreds of miles away – a toxicologist explains why - information](https://s3.amazonaws.com/arc-authors/washpost/461fb228-27ac-4715-9be3-f95f56b20a56.jpg)
Hazardous air quality hit NYC as smoke moves from Canada wildfires
![Canadian wildfire smoke was thick in the air over New York's Yankee Stadium on June 6, 2023. AP Photo/Frank Franklin II Wildfire smoke can harm human health, even when the fire is hundreds of miles away – a toxicologist explains why - information](https://media.cnn.com/api/v1/images/stellar/prod/230608131205-03-canada-smoke-in-us-gallery-update-0608.jpg?c=original)
Photos: Canadian wildfires impact US air quality
![Canadian wildfire smoke was thick in the air over New York's Yankee Stadium on June 6, 2023. AP Photo/Frank Franklin II Wildfire smoke can harm human health, even when the fire is hundreds of miles away – a toxicologist explains why - information](https://d1i4t8bqe7zgj6.cloudfront.net/06-07-2023/t_3850a9a4dbb24108b7540ab40a64cea5_name_IMG_0281_MOV_00_00_13_06_Still001.jpg)
Hazardous air quality hit NYC as smoke moves from Canada wildfires
![Canadian wildfire smoke was thick in the air over New York's Yankee Stadium on June 6, 2023. AP Photo/Frank Franklin II Wildfire smoke can harm human health, even when the fire is hundreds of miles away – a toxicologist explains why - information](https://arc-anglerfish-washpost-prod-washpost.s3.amazonaws.com/public/U5SHARA6UXXSUWXPMGAV7EUPF4.jpg)
Hazardous air quality hit NYC as smoke moves from Canada wildfires