By exploring how chemical contaminants move through the environment and affect aquatic food webs, Upal Ghosh, Ph.D., of the University of Maryland, Baltimore County (UMBC), aims to develop and implement technologies to help ecosystems recover from pollution.
With consistent NIEHS funding since 2007, Ghosh studies contaminants called polychlorinated biphenyls (PCBs), which can build up in organisms over time and along the food chain. Ghosh assesses pollutant bioavailability, or the amount of a contaminant available for uptake by fish and other organisms, with a particular focus on PCBs.
“During my undergraduate studies in chemical engineering, I got to visit different industrial sites and understand how we produce chemicals in bulk,” Ghosh said. “Although chemical industries provide many benefits for people — producing thousands of consumer products we use today — I was disappointed to see the problems that occur when chemicals like PCBs are mismanaged and enter the environment.”
His goal is to use nature-based strategies to clean up contaminants and reduce exposures in aquatic organisms and humans alike.
PCBs Pose a Public Health Issue
PCBs are a group of chemicals formerly used in many industrial and consumer products, such as electrical equipment, insulation, paint, and plastics. Although the federal government banned PCB production in 1979, the compounds persist in soils, sediments, and water bodies due to their stable chemical structure.
Exposure to PCBs has been associated with a wide variety of health effects, including liver problems, poor birth outcomes, hormone disruption, and cancer. In general, people are exposed to PCBs by eating contaminated fish, meat, or dairy products.
“If we can limit the amount of PCBs bioavailable to fish, we can also help protect human health,” Ghosh explained.
To better understand PCB accumulation in organisms, Ghosh’s team has been studying the Anacostia River in Washington, D.C., which faces ongoing PCB contamination. The river’s long history of urbanization and industrialization has resulted in pollution, poor water quality, and contaminated sediments in the riverbed.
The team deployed passive samplers and freshwater mussels into the Anacostia River as dual methods to identify PCB sources. Mussels are sedentary, long-lived filter feeders that have been shown to accumulate contaminants without metabolizing them. They then developed models to accurately predict PCB accumulation in mussels and different fish species in the river.
According to Ghosh, this research demonstrated that controlling ongoing PCB inputs from one heavily impacted tributary was critical for the reduction of PCB levels in fish.
“At many contaminated sites, we found that PCB hotspots were located near disadvantaged communities, which poses an environmental justice and health equity issue for the people who live there,” Ghosh said.
image credits:
Photo courtesy of Upal Ghosh