Mercury pollution has been a persistent problem in lakes and oceans, accumulating in fish and ultimately posing a threat to human health. Kate Tepper, a postdoctoral researcher at Macquarie University in Australia, along with her colleagues, have taken a new approach to tackle this issue. They have genetically engineered zebra fish and fruit flies to break down methylmercury, a toxic form of mercury that bioaccumulates in organisms.
By introducing genes from Escherichia coli that produce a conversion enzyme into the embryos of these animals, the researchers were able to significantly reduce the levels of mercury in the modified zebra fish and fruit flies. The modified zebra fish showed a 64% reduction in mercury levels, while the fruit flies exhibited an 83% decrease. This innovative approach opens up the possibility of using genetically modified animals as a means of bioremediation to clean up mercury contamination in aquatic ecosystems.
Bioremediation, the use of biological processes to remove contaminants, is not a new concept. Previous studies have shown that plants and bacteria with specific genes can detoxify pollutants. However, by targeting animals that are already contaminated with mercury, Tepper’s team aims to address the issue at its source. This method could potentially disrupt the bioaccumulation of mercury on a local scale, especially in areas heavily impacted by mercury pollution.
Robert Mason, a marine scientist at the University of Connecticut who specializes in mercury research, acknowledges the potential of using modified animals for clean-up efforts. However, he highlights the challenge of elemental mercury reverting back to methylmercury once released into the atmosphere. Despite this limitation, introducing genetically modified fish into highly contaminated sites, such as those affected by artisanal gold mining in Africa, Indonesia, and the Amazon, could have a significant impact on reducing mercury exposure for communities reliant on fishing.
Before field trials can be conducted, safety measures must be established to contain the genetically modified organisms. Tepper envisions controlled experiments in small lakes to assess any unintended ecological effects. Looking ahead, she believes that this approach could be extended to address other pollutants like microplastics, pharmaceuticals, and PFAS. The concept of engineering animals for bioremediation holds promise for a more sustainable and effective way to mitigate pollution in our environment.
