Asphalt, the material used to build roads and parking lots around the world, is a silent cause of air pollution that is damaging the environment and the people who live in it, according to a new study by Yale University. The study found that on hot sunny days, the effect is most severe, with intense heat increasing the amount of harmful particles released into the air by asphalt.
According to the new study, “very little” pollution from asphalt is taken into account when assessing air quality in major cities. This is unfortunate because the material contains harmful contaminants that are slowly released back into the environment, especially when the material is baked in the hot sun.
As air pollution from combustion, such as car engines, decreases, experts note an increase in non-incendiary air pollutants because of their contribution to organic compounds and secondary organic aerosols (more commonly known as SOA). These SOAs are a major source of air pollutants called PM2.5. PM2.5 refers to polluting particles with a diameter of less than or equal to 2.5 microns.
PM2.5 particles have a significant negative impact on public health, so it is necessary to monitor air quality and take measures to curb these pollutants. Tests involving asphalt heating to different temperatures have found that this will involve emissions of various organic compounds, a problem that is most severe at higher temperatures but will eventually last for a long time.
In addition, the study found that temperature is not the only factor that increases emissions of asphalt pollution, and solar radiation also plays an important role. Ultimately, new, greener alternatives to asphalt are needed to curb this particular source of air pollution.