What’s in your water?

For a scholar whose research focuses on aquatic envi­ron­mental chem­istry, Philip Larese-​​Casanova spends little time doing research in the envi­ron­ment. “I don’t take water sam­ples and I don’t go to drinking water plants or waste­water treat­ment plants,” said the assis­tant pro­fessor of civil and envi­ron­mental engi­neering.

That’s because most of the pol­lu­tants Larese-​​Casanova is inter­ested in haven’t been around long enough to make that kind of work fea­sible. Or, if the mate­rials them­selves aren’t brand new, the processes he’s inves­ti­gating are.

“If we know how a mate­rial is going to behave, then we can design cleanup strate­gies,” he said. Under­standing the behavior has to come first. That is, how will this new material—when dis­persed in water and exposed to sun­light, for example—react with the nearby min­erals and organic mate­rial. Will it dis­solve in the water and be ingested by fish, or will it leach out into the soil?

Backed by funding from a recently awarded National Sci­ence Foun­da­tion CAREER grant, Larese-​​Casanova is expanding his research in metallic water pol­lu­tants to include quantum dots—mixed-metal mate­rials that are used in energy pro­duc­tion and elec­tronics and are smaller than even the smallest nano­ma­te­rials. As researchers learn more about quantum dots, they are primed to become a ubiq­ui­tous mate­rial in modern tech­nolo­gies. Under­standing their impact on the envi­ron­ment is there­fore crit­ical, Larese-​​Casanova said.

“We have a good idea of how metallic nanopar­ti­cles behave in water because there’s a large body of research,” Larese-​​Casanova explained, “but now quantum dots are at even a smaller size.” By virtue of their size, the same metals can dis­play dras­ti­cally dif­ferent prop­er­ties in the environment.

The NSF grant has enabled Larese-Casanova’s team to acquire a device that blasts mol­e­cules apart into their com­po­nent ele­ments. “The goal is to use this instru­ment for simul­ta­neous mea­sure­ment of dis­solved and par­tic­u­late metals,” he said. The method will allow the team to inves­ti­gate the aquatic behavior of quantum dots at a variety of levels, mean­ingful once they reach our actual rivers and streams.

Quantum dots are already being researched in lab­o­ra­to­ries around the globe and may soon power our cell phones. Larese-​​Casanova wants to know what impact these tiny par­ti­cles will have on the aquatic sys­tems in which they end up. But that ques­tion cannot be answered without first under­standing the very basic level of quantum dot behavior in water.

“I want to pro­tect our water resources,” he said. “There are so many aspects to the dis­cus­sion from drinking water to waste waters. I’d like to do my part.” While his part takes place in a series of beakers and vials on the lab­o­ra­tory bench top, it is clear that his work lays the nec­es­sary foun­da­tion for other researchers to build upon.

See more here.

Related Faculty: Philip Larese-Casanova

Related Departments:Civil & Environmental Engineering