Smoke from fires in Canada is traveling thousands of miles. Here’s how to protect yourself

More than 850 wildfires are currently burning in Canada—and the smoke is reaching cities thousands of miles away, from Chicago to New York City. Next week, it’s expected to reach Europe. If the sky is a hazy shade of yellow where you live, here’s what you should know about the potential health impacts. Even long-distance smoke is harmful Tiny particles of smoke called PM 2.5—20 to 30 times smaller than the width of a human hair—can easily enter your lungs and even your bloodstream. The effects…