Nanomaterials will soon find effective use in the construction industry but widespread use in building materials comes with potential environmental and health risks when those materials are thrown away, according to new research.
The study, by Rice University engineering researchers, appears in ACS Nano.
"The advantages of using nanomaterials in construction are enormous. When you consider that 41 percent of all energy use in the U.S. is consumed by commercial and residential buildings, the potential benefits of energy-saving materials alone are vast," said study co-author Pedro Alvarez, Rice's George R. Brown Professor and chair of the Department of Civil and Environmental Engineering. "
"But there are reasonable concerns about unintended consequences as well. The time for responsible lifecycle engineering of man-made nanomaterials in the construction industry is now, before they are introduced in environmentally relevant concentrations," he added.
Alvarez and co-authors Jaesang Lee, a postdoctoral researcher at Rice, and Shaily Mahendra, now an assistant professor at the University of California, Los Angeles, note that nanomaterials will likely have a greater impact on the construction industry than any other sector of the economy, after biomedical and electronics applications.
The researchers cite dozens of potential applications. For example, nanomaterials can strengthen both steel and concrete, keep dirt from sticking to windows, kill bacteria on hospital walls, make materials fire-resistant, drastically improve the efficiency of solar panels, boost the efficiency of indoor lighting and even allow bridges and buildings to "feel" the cracks, corrosion and stress that will eventually cause structural failures. n compiling the report, Lee, Mahendra and Alvarez analysed more than 140 scientific papers on the benefits and risks of nanomaterials. In addition to the myriad benefits for the construction industry, they also identified potential adverse health and environmental effects.
In some cases, the very properties that make the nanomaterials useful can cause potential problems if the material is not disposed of properly. For example, titanium dioxide particles exposed to ultraviolet light can generate molecules called "reactive oxygen species" that prevent bacterial films from forming on windows or solar panels. This same property could endanger beneficial bacteria in the environment.
"There are ways to engineer materials in advance to make them environmentally benign. There are also methods that allow us to consider the entire lifecycle of a product and to ensure that it can be recycled or reused rather than thrown away. The key is to understand the specific risks and implications of the product before it it is widely used," Alvarez said. (ANI)