Since the early 1950s, East Fork Poplar Creek in Oak Ridge has been contaminated with large amounts of mercury as a result of activity at the Y-12 National Security Complex, where the creek originates.

When mercury interacts with certain microbes in soil and waterways, it turns into methylmercury, a neurotoxin. Once consumed by surrounding fish, methylmercury can move up the food chain and pose a health risk to humans.

ORNL Graduate Student Research Profile: Jada Hoyle-Gardner
Through the Higher Education Research Experiences Program, doctoral student Jada Hoyle-Gardner contributed to mercury research efforts at Oak Ridge National Laboratory.

Scientists at Oak Ridge National Laboratory (ORNL) are trying to gain a better understanding of the factors that transform mercury to methylmercury in East Fork Poplar Creek.

Jada Hoyle-Gardner, a doctoral student in environmental sciences at Florida Agricultural and Mechanical University (FAMU), recently contributed to these research efforts during a summer internship through the Higher Education Research Experiences (HERE) Program at ORNL.

“This is a once-in-a-lifetime chance (to conduct research) at a highly recognized laboratory. Whatever one’s STEM major is, there is a research project to match them with,” she said. “A person will leave more knowledgeable than when they entered the program.”

Hoyle-Gardner was part of the ORNL Mercury Science Focus Area team in the Environmental Sciences Division.

Under the mentorship of Scott Brooks, Ph.D., Distinguished R&D Scientist, and Grace Schwartz, Ph.D., postdoctoral fellow, Hoyle-Gardner investigated sediments found in East Fork Poplar Creek as well as those in Hinds Creek, a nearby waterway that was used as a reference site because of its low levels of mercury.

Hoyle-Gardner analyzed the kinetics behind how much mercury stays on the sediment and how much is dissolved in the water. This information will offer insight into the amount of mercury available to the microbes that carry out the transformation process to methylmercury.

On a typical day, Hoyle-Gardner gathered water and sediment samples from the waterways. After filtering the water and sieving the sediments, she ran kinetic experiments to collect mercury, either in a dissolved form or attached to the sediment, and studied the results.

Through her HERE internship, Hoyle-Gardner learned new laboratory techniques, improved her organizational skills and formed valuable connections with fellow interns and ORNL staff.

“This is a once-in-a-lifetime chance (to conduct research) at a highly recognized laboratory. Whatever one’s STEM major is, there is a research project to match them with,” she said. “A person will leave more knowledgeable than when they entered the program.”

After she completes her doctoral program at FAMU, Hoyle-Gardner hopes to work at the Centers for Disease Control and Prevention (CDC) or a similar research facility.

“I am interested in applying myself in areas like environmental toxicology and public health, and the CDC has various opportunities matching this interest,” she said.

She also aspires to teach science to young people, especially those in middle school and high school.

“I have realized that is the time a lot of children become disinterested in STEM courses and, as a result, begin trailing behind,” she said. “I want to be able to catch them and get them reinterested in STEM and instill confidence that science can be educational and fun.”

The HERE program is administered by the Oak Ridge Institute for Science and Education (ORISE) for the U.S. Department of Energy.