Canada is dealing with a series of intense wildfires that have spread from the western provinces to Quebec, with hundreds of forest fires burning. Wind has carried smoke from the fires southward, triggering air quality alerts throughout the United States. The U.S. Environmental Protection Agency Tuesday issued a poor air quality alert for New England, a day after parts of Illinois, Wisconsin and Minnesota received a similar advisory. Last week, U.S. officials as far south as Maryland, Baltimore, Virginia and Pennsylvania reported being impacted by the wildfires. Fine-particle pollution — known as “PM 2.5” — is what’s being measured. The tiny particles are small enough to get past airway defenses and cause breathing problems.