While pursuing a master’s in public health from Eastern Kentucky University, Mary Sheldon earned an accolade many researchers spend their whole careers hoping for. Her capstone research was recently the cover story of a prominent peer-reviewed journal.
The report, titled “Pesticide Contamination in Central Kentucky Urban Honey: A Pilot Study,” was a collaboration between Sheldon; Dr. Clint Pinion, her faculty mentor and an associate professor in EKU’s Environmental Health Science department; and Dr. Anne Marie Zimeri of the University of Georgia-Athens. Through in-depth chemical analyses on locally sourced honey, they identified the presence of heavy metals and pesticides in the majority of the samples.
“I don’t know that I would call it surprising as much as disturbing,” Sheldon said. “We found toxins such as dichlorodiphenyltrichloroethane, or DDT, at substantial levels still in the environment. DDT was developed as the first of the modern synthetic insecticides in the 1940s. The EPA banned in 1972 based on its adverse environmental effects, such as those to wildlife, as well as its potential human health risks.”
The research appeared on the cover of the July/August issue of the “Journal of Environmental Health,” bringing an unforeseen level of visibility to the problem her research highlighted. More than 72 percent of urban honey samples “exhibited levels of pesticides exceeding U.S. Environmental Protection Agency tolerable daily intake levels,” the report said.
The study would not have been possible if a desire to learn had not sent Sheldon back to school after three decades in the workforce. At 61 years old, she has had a successful career as a dental ceramist, making crowns, bridges and other dental inserts. She earned her first degree — an associate’s of applied science in dental technology — at Bluegrass Community & Technical College in 1985.
However, Sheldon has been interested in the natural environment and entomology since participating in 4-H in grade school. She enrolled at EKU as a sociology major, graduating with her bachelor’s degree in 2013. EKU’s small class sizes and focus on mentorship made it the perfect place to begin pursuing a new path of study. In the course of her studies, she became more interested in environmental sociology and decided to pursue a master’s of public health.
“It was like a whole new world opened up before me,” she said. “I became much more involved in my community by helping to educate those concerned about the environment we live in.”
Her beekeeping is part of those education efforts. Sheldon now teaches other Kentuckians about the honeybee and its ecosystem. With the help of another faculty mentor, sociology professor Dr. Stephanie McSpirit, Sheldon was introduced to Dr. Tammy Potter and began working for Coal Country Beeworks, an initiative to reclaim strip mines to convert into honey bee habitats. This evolved into a collaboration with Green Forests Work and the University of Kentucky to further promote educational outreach. She has also started a small business, Bee Genuine, selling honey and beeswax-based products.
Sheldon and Pinion began her capstone project when they received a major university grant to test local honey for pesticides in February 2017. Initial testing for mosquito abatement pesticides showed no contamination and the project seemed at a dead end. A chance meeting, however, would change its course.
Pinion met Zimeri at a national conference. While discussing Sheldon’s project, Zimeri revealed that she specializes in heavy metal and organochlorine pesticide analysis and agreed to test Sheldon’s samples. As a result, the group discovered the presence of pesticides and heavy metals that have long been banned in the U.S.
Pinion, Sheldon and Zimeri drafted an article detailing the results of their research and submitted it to the “Journal of Environmental Health” in September 2018. The following March, they learned that it would be the cover story of the July/August issue. The group presented their findings at the 2018 National Environmental Health Association Annual Education Conference held in Anaheim, California.
According to Pinion, Sheldon’s success is in part due to her long career outside of academia.
“She definitely was secure with herself and very confident,” Pinion said. “When you work with a student like Mary, you see the years of professionalism in the way that she carries herself, corresponds in emails or sends updates on her research.”
Pinion and Sheldon are currently applying for more grants to continue the research and spreading the word about how to limit contamination in local hives.
“One of the things that we can tell amateur beekeepers is that by changing out the actual comb, you can minimize the amount of pesticide present in the comb,” Pinion said. “If you use the same combs over and over, you can essentially have a buildup of pollutants. The pollutants that are there will persist.”
Both the importance of her research and that a peer-reviewed journal chose to feature it so prominently have encouraged Sheldon to consider opportunities for further study.
“When you’re passionate about a subject, it is always gratifying to be recognized by your peers and also to be part of the educational process that helps further research,” she said. “This would not have happened if EKU had not provided me with some outstanding professors who are patiently dedicated to their student’s growth and learning.”