As the Community Assessment of Freeway Exposure and Health study starts its fourth year, researchers are saying that if you live near Interstate 93, what you can’t see can hurt you. The team behind the $2.5 million, five-year study shared an interim preliminary report with Somerville community partners on May 19. Living within 300 to 400 meters of a highway is “linked with higher rates of heart disease, asthma, and lung cancer,’’ according to a fact sheet. “What people near the highway talk about is this black soot’’ that coats their window sills, said principal investigator Doug Brugge of Tufts University. But there’s also pollution you can’t see: ultrafine particulates of carbon monoxide and other toxins. “The particles are invisible and odorless . . . you don’t have any sense of whether they’re high or not high,’’ Brugge said. In fact, the levels change rapidly depending on the weather and season, with winter generally the worst time. Learn more at tufts.edu.
— Danielle Dreilinger