February 10, 2016 | Erin Bluvas, bluvase@sc.edu 

The National Institute of Environmental Health Sciences has awarded Assistant Professor Sarah Rothenberg (Department of Environmental Health Sciences) with an R21 grant ($386,741) to research methylmercury exposure through rice ingestion and offspring development in China. The study will also look at how gut microbiota metabolize methylmercury. The Arnold School’s Center for Research in Nutrition and Health Disparities, where Rothenberg serves as a faculty affiliate, will provide pre- and post-award support.

Methylmercury is a potent neurotoxin due to its ability to cross both blood-brain and placental barriers. About 95 percent of dietary methylmercury is absorbed into the bloodstream. It is then transported throughout the body and accumulated in tissues, including the brain, where it can lead to developmental delays.

“Gut microbes in our gastrointestinal tracts play an important role in metabolizing xenobiotics, including mercury,” says Rothenberg. “However, there are a lot of gaps in our understanding.”

To address these knowledge gaps, Rothenberg will examine the bi-directional associations between gut microbes, dietary methylmercury intake (through rice) and the accumulation of methylmercury in tissues of humans—more specifically, children. Results from this study will clarify our understanding of the mechanisms by which gut microbes contribute to variability in children's methylmercury metabolism and exposure, potentially impacting their development.

“This research is part of the emerging field relating gut microbiota to human health,” Rothenberg says. “We hope these results will help clarify how gut microbiota metabolize methylmercury and eventually lead to nutritional therapies to reduce exposure to this potent neurotoxin.”