Taking on Toxic Metals
Raissa Mendonca’s research focuses on how environmental disturbances affect aquatic communities and ecological processes.
Text and photo by Jim Maxwell, BS ’00, MS ’11
Though she had an interest in science at an early age, Raissa Mendonca had no idea she would end up more than 4,000 miles away from her hometown of Recife, Brazil, studying and conducting award-winning ecological research at Kent State University.
Accepted into Science Without Borders, an exchange program sponsored by the Brazilian government, in 2012 she spent her junior year away from the and attended the University of Michigan. There, she worked with Dave Costello, PhD, who at the time was a postdoctoral researcher at Allen Burton’s Ecotoxicology Lab. Now he is an assistant professor in biological sciences at Kent State’s College of Arts and Sciences—and her current advisor.
While pursuing a PhD at Kent State, Mendonca conducts research in Costello’s lab that focuses on ecotoxicology and biogeochemistry and how environmental disturbances affect aquatic communities and ecological processes.
One of her recent projects resulted in her being the first author on a peer-reviewed journal article, “Metal oxides in surface sediment control nickel bioavailability to benthic macroinvertebrates,” in Environmental Science & Technology.
Her research also earned her the Chris Lee Award for Metals Research, presented jointly by the Society of Environmental Toxicology and Chemistry and the International Copper Association.
The $5,000 award money is helping her fund the experiments for the last two data chapters of her dissertation, looking at the toxic effects of nickel to benthic bacteria (microbes that live attached to sediment) involved in the process of forming and dissolving metal oxides.
“If we understand when these metals are harmful, we can better target when we need to clean up systems and when we can let them recover on their own.”
“If nickel is stuck onto the surface of these metal oxides it is not available for biological uptake,” Mendonca says, “and, therefore, does not exert its toxic effects on organisms that live in or on the sediment.”
“We found that at a macroscale, rivers and streams have capacity to ‘soak up’ some of the contaminants,” says Costello. “If we understand when these metals are harmful, we can better target when we need to clean up systems and when we can let them recover on their own.
“Raissa did complicated field work in a remote part of Manitoba, Canada,” he adds. “She had to understand geology, chemistry and biology to understand the process. That is the way the field is going—integrated projects that are not just in a lab or beaker.”
Mendonca plans to graduate in spring 2020 and pursue a postdoctoral fellow position, within the field of geomicrobiology, where she can continue to explore her research interests.