A new study reveals roads may be producing more air pollution than the vehicles that drive on them.<br />Yale University researchers found that numbers didn't add up when they tried to account for all the sources of existing air pollution in Los Angeles.<br />According to Science Magazine, the researchers turned to newly-paved asphalt roads and roofs, which up until now had been overlooked in such studies.<br />They found the greatest amount of semivolatile organic compounds escaped when the pavement was heated to 140°C. That's the temperature of road-paving.<br />Emissions fell as the asphalt cooled, but remained constant and significant at 60°C, a typical temperature for asphalt in Los Angeles during the summer.<br />This suggests that asphalt could be a long-lasting source of pollution, and thus belongs in official inventories of air pollution sources.
