Genetic tool aids fight against arsenic groundwater contamination

  • Research


A team of researchers from Utah State University College of Engineering have developed a new tool to simplify the process of identifying the bacterial species responsible for releasing a form of arsenic that contaminates the water supplies of millions of people around the world.

The findings have been published in the latest issue of Applied and Environmental Microbiology. The bacteria under investigation reduce arsenic V (arsenate) to arsenic III (arsenite), which is more toxic and more mobile, moving more easily into the environment and groundwater.

The tool is based on use of a new primer, a short strand of DNA that targets the arsenic reductase gene that gives bacteria the ability to reduce arsenate. Before this primer was created, it was necessary to grow the bacterial cells in a laboratory, extract their DNA and amplify the gene, which often reduced the microbial diversity and biased the results.

During the study the team took groundwater samples from 20 privately-owned wells in Utah, which showed 20% had arsenate and arsenite concentrations above the 10µg/litre limit. The researchers also found a match between samples with high arsenite concentrations and an abundance of the arsenate reductase genetic material.


  • groundwater, arsenic, water quality monitoring