Asphalt is a near-ubiquitous substance—it’s found in roads, on roofs and in driveways—but its chemical emissions rarely figure into urban air quality management plans. A new study now finds that asphalt is a significant source of air pollutants in urban areas, especially on hot and sunny days. Yale researchers found that common road and roofing asphalts produced complex mixtures of organic compounds, including hazardous pollutants, in a range of typical temperature and solar conditions. An open-access paper on their work is published in the journal Science Advances . Asphalt’s life cycle and temperature-dependent emissions. (A) Different stages in asphalt’s life cycle with potential to emit reactive organic gases into the atmosphere. (B) Temperature dependence of total gas-phase emissions from asphalt, ranging from in-use (40 °C to 60 °C) and storage (80 °C to 140 °C) to paving and overheating (120 °C to 200c°C) temperature conditions (filled circles). The corresponding […]