An anonymous reader shares a report: The smell of summer in Los Angeles, or any major city, is often tinged with asphalt. A freshly paved road or a new tar roof doesn’t just wrinkle your nose, however: A new study suggests fresh asphalt is a significant, yet overlooked, source of air pollution. In fact, the material’s contribution to one kind of particulate air pollution could rival or even exceed that of cars and trucks. “It’s a super cool paper,” says Allen Robinson, an environmental engineer at Carnegie Mellon University who was not involved with the research. “Asphalt could be a big, important contributor” to air pollution, he says. Air quality has improved over the past several decades in California and many other parts of the United States, largely because of cleaner exhaust from vehicles and power plants. Despite that, air pollution still contributes to many health problems — ranging from asthma to heart attacks. And many sources of air pollution continue to be a problem, from livestock emissions to volatile organic compounds from paints, cleaning products, and personal care products (especially those that contain fragrances, such as shampoo).
Yet, when scientists looked at all the known sources of air pollution in Los Angeles and the surrounding areas, they didn’t add up. Some sources had not yet been identified. “Asphalt was something that jumped out to us,” says Drew Gentner, an environmental engineer at Yale University who led the new study. The material, made from crude oil or similar substances, contains the kinds of semivolatile organic compounds that lead to some types of air pollution. There’s also a lot of it. Gentner and colleagues gathered two types of fresh road asphalt and heated them in a laboratory furnace. They also tested new asphalt shingles and liquid asphalts used for roofing. They reasoned that new material should release more chemicals than older material, and they wanted to see how the emission rate changes as the fresh asphalt ages.
of this story at Slashdot.
Source:: Slashdot