Scientists Tricked Bacteria Into Cleaning Up a Polluted Aquifer in SpainOctober 24, 2019
Scientists have been able to trick locally found bacteria to clean a polluted aquifer by injecting a safe and naturally occurring chemical into the water. Chlorinated ethenes are a group of chemicals that were once used as industrial solvents and cleaners. These have polluted groundwater through the years across the nation, and cannot be broken down easily. Researchers continue to look for ways to remove them from the environment but only realized recently, that a genus of bacteria can partially breakdown the chemical but cannot finish the job.
A Spanish team was able to decontaminate the entire aquifer by adding lactic acid to the water. This approach is called biostimulation. Researchers have shown numerous studies which show that organohalide-respiring bacteria can break down chlorinated ethenes.
The team of scientists focused on an industrial site in Barcelona which had a contaminated aquifer due to chlorinated ethenes. They collected a sample of the water to create microcosms of the microbes. Then, they added sodium lactate to the batches collected. With stimulation from the lactic acid, the bacteria broke down the chemical completely whereas, without the stimulation, the bacteria left behind some toxic byproducts.
The experiment began in 2016, and when it was successful, another full-scale treatment was attempted in 2017. It turned out, that by 2018, the aquifer contained nontoxic ethenes. In most cases of groundwater. The levels of the chemical were undetectable.
While the chemical was broken down, in some cases it left behind vinyl chloride which is toxic. Another byproduct was Methane, a greenhouse gas. The technique, however, showed lowered chlorinated ethane concentration where other strategies had failed badly. Here’s hoping the bacteria can fix the planet before it kills us all!