Newswise – A researcher at Florida State University will conduct a study on how bacteria can be used to remove carcinogens from groundwater through a $ 1.4 million grant of the National Institute of Environmental Health Sciences.
Researchers from FAMU-FSU College of Engineering will collaborate with Texas Tech University to study a bioremediation method that could eliminate health risks such as chlorinated volatile organic compounds (CVOCs) and 1,4-dioxane faster than current technology. The process could be an effective tool for cleaning up so-called Superfund sites, sites contaminated with hazardous waste and deemed a priority for cleanup by the US Environmental Protection Agency.
“The bioremediation techniques we use have the potential to pick up carcinogens from polluted places that normally require a long-term response,” said Youneng Tang, assistant professor in the Department of Civil and Environmental Engineering.
The research uses bacteria that thrive on what are called macrocyclic molecules, which have unique geometry and internal chemistry that allows them to individually bind to molecules like CVOCs and 1,4-dioxane.
This is especially important for the remediation of groundwater containing these compounds, as it needs different conditions to biodegrade. CVOCs require anaerobic conditions (without oxygen) to biodegrade, but 1,4-dioxane is metabolized under aerobic conditions (requiring oxygen).
“The remediation process requires two steps,” Tang said. “First, we promote the growth of the dechlorinating biofilm on one type of material to biodegrade CVOC anaerobically, and then we use another macrocyclic material to produce a very efficient culture to aerobically metabolize 1,4-dioxane.”
As part of off-site treatment of contaminants, researchers pack a reactor with absorbent materials. Then they pump the contaminated groundwater through the reactor to allow bacteria to grow and break down the contaminant.
For on-site treatment, they reduce an absorbent material to a microscopic size and inject it directly into the soil. The material then absorbs contaminants and bacteria which can degrade the pollutants.
“We hope that our research will allow us to better understand the mechanisms of how the new sorbents improve bioremediation,” Tang said. “Our long-term goal is to make biological processes more efficient and more sustainable in the near future.”
The researchers plan to conduct two long-term studies at a Superfund site and are teaming up with Geosyntec Consultants of Huntington Beach, Calif., To test the feasibility of the proposed remediation.
Yuexiao Shen, assistant professor of civil engineering at Texas Tech University, is the co-principal investigator of this project.