Though she had an interest in science at an early age, Raissa Mendonca had no idea she would end up over 4,000 miles away from her hometown of Recife, Brazil studying and doing award-winning ecological research in the College of Arts and Sciences at 鶹Ƶ in Kent, Ohio. She probably did not expect to be wearing a bug net over her head in Manitoba either.
Like many students, when she realized opportunities at home were relatively limited she figured graduate school was the logical next step to as she says, “extend the problem of getting a job.”
Opportunity knocked for Raissa in 2012, when she was accepted into a program sponsored by the Brazilian government called Science Without Borders. Through this exchange program, she was able to spend her junior year away from Universidade Federal de Pernambuco and attend the University of Michigan. There she had her first opportunity to work with her current advisor Dr. Dave Costello (a postdoc at the time) and other researchers in Allen Burton’s Ecotoxicology Lab in the School of Natural Resources & Environment at the University of Michigan.
“I helped with the set-up of several projects within the lab and had the opportunity to work with Dave for the whole year,” Mendonca said. “As I was ready to apply for grad school, Dave had just secured a faculty job in the Department of Biological Sciences at 鶹Ƶ and that seemed like a great opportunity to keep working with him.”
Award-Winning Research
Now, while pursuing her Ph.D. at 鶹Ƶ, 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 first author on a peer-reviewed journal article “Metal oxides in surface sediment control nickel bioavailability to benthic macroinvertebrates” in the journal Environmental Science & Technology and earned her a $5,000 award to continue pursuing her research.
For this research work, she earned the Chris Lee Award for Metals Research presented jointly by the Society of Environmental Toxicology and Chemistry (SETAC) and the International Copper Association (ICA). To learn more about the award, visit:
The 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. In essence, she assesses how “sticky” certain metal oxides, such as iron and manganese oxides, are and how much dissolved nickel they “trap”. Ultimately, she wants to explore the feedbacks between nickel toxicity to those bacteria and its bioavailability to benthic organisms.
“If nickel is stuck onto the surface of these metal oxides, it is not available for biological uptake and therefore does not exert its toxic effects on organisms that live in or on the sediment,” Mendonca said.
Understanding how toxic metals behave in stream systems is imperative to determine the degree of impairment of exposed systems and to inform remediation strategies. She wants to know where and what it sticks to, how toxic it is, and what affects its toxicity within that system.
“One of the interesting things that we found in this paper is that at a bigger, macroscale a lot of these rivers and streams have capacity to sort of soak up some of the contaminants and not have them influence the biota,” Costello said. “So that, in some ways, is a little bit refreshing. If we understand when these metals are harmful, we can better target when we need to go in and clean up systems and when we can leave them alone and let them recover naturally on their own.”
“The project that Raissa did was very complicated field work in a remote part of Manitoba, Canada,” Costello said. “She had to understand geology, chemistry, and biology to understand the process. That is the way the field is going and that is what society really wants to see…these integrated projects that are not just in a lab, in a beaker, or exposing an organism to a chemical. That’s not ecotoxicology.”
Getting Started
Mendonca strongly believes her research experiences early on had a great influence over where she is today.
“I was always interested in science in school,” Mendonca said. “Then as soon as I got into undergrad school, my uncle, a biologist, began asking me if I’d asked any of the professors if I can get into the labs and get my hands on projects and what not?”
During the second semester of her freshman year, Raissa joined a biochemistry lab because she was approached by one of the teaching assistants (TA) asking if she wanted to do some research. She stayed in that lab for about six months until the project concluded.
“I started looking for another lab and I just kind of stumbled upon the ecotoxicology lab,” Mendonca said. “I didn’t even really know what ecotoxicology was at the time. There was a posting for this lab, so, I just went to the professor to talk about what it was and what he was looking for. My grades helped me get my foot in the door quickly, but then I got to learn a lot about ecotoxicology and became really interested in it. So, it was kind of a lucky shot, but it worked out.”
“Ironically, that’s kind of funny because when Raissa became a TA in the intro labs here, one of the first tasks I gave her was ‘look for the good students and bring them into my lab’ which is the exact same thing as what got her started,” Costello said.
Undergraduates interested in research opportunities in the Department of Biological Sciences should visit: /biology/kent-campus-faculty-research-expertise
Bright Future
Mendonca plans to graduate in Spring 2020 and hopes to attain a postdoctoral fellow position, within the field of geomicrobiology, where she can continue to explore her research interests.
“I think my exposure to science and research early on in my undergraduate career helped me quickly realize that I am thoroughly captivated by critical thinking, learning, and experimentation,” Mendonca said. “This encouraged me to keep pursuing independent study and lab opportunities, but also helped me find ecotoxicology.”
She said that some of her favorite experiences at 鶹Ƶ so far involve the daily camaraderie with her lab mates and peers. “The collaboration and mutual support have been instrumental in keeping me motivated, excited, and looking forward to the next steps,” Mendonca said.
As you might expect from an ecologist, when she is not studying or working in the lab she says she likes to go hiking or biking in the Cuyahoga Valley National Park. She also likes watching Netflix too. Especially The Office, which she admittedly binge watches. “Oh, it’s my third time through,” Mendonca said with a laugh.
Broad areas of study in Costello’s Lab
Costello’s lab currently has many different projects going on related to how humans influence freshwater ecosystems, whether that is nutrient pollution, or pollution from contaminants like heavy metals. They also conduct some studies of invasive species.
“We’re looking to better understand how these anthropogenic stressors influence the functioning of these freshwater ecosystems,” Costello said. “We like to look at things at big scales, trying to understand the whole stream ecosystem processes. We want to know how well the stream produces new biomass and how well it is supporting the food web. We’re also starting to look at harmful algal blooms in the Great Lakes trying to understand the role trace metals and nutrients have on algal blooms.”
To learn more about Dr. Costello’s lab, visit:
Media Contacts:
Jim Maxwell, 330-672-8028, jmaxwel2@kent.edu
Dave Costello, 330.672.2035, dcostel3@kent.edu