Bacteria Becomes Resistant When Exposed To Li-Ion Nanoparticles

Over the last two decades, nanotechnology has improved many of the products we use every day from microelectronics to sunscreens. Nanoparticles (particles that are just a few hundred atoms in size) are ending up in the environment by the ton, but scientists are still unclear about the long-term effects of these super-small nanoparticles. In a first-of-its-kind study, researchers have shown that nanoparticles may have a bigger impact on the environment than previously thought.

Researchers from the National Science Foundation Center for Sustainable Nanotechnology, led by scientists at the University of Minnesota, found that a common, non-disease-causing bacteria found in the environment, called Shewanella oneidensis MR-1, developed rapid resistance when repeatedly exposed to nanoparticles used in making lithium ion batteries, the rechargeable batteries used in portable electronics and electric vehicles. Resistance is when the bacteria can survive at higher and higher quantities of the materials, which means that the fundamental biochemistry and biology of the bacteria is changing.

At many times throughout history, materials and chemicals like asbestos or DDT have not been tested thoroughly and have caused big problems in our environment,” said Erin Carlson, a University of Minnesota chemistry associate professor in the University’s College of Science and Engineering and the lead author of the study. “We don’t know that these results are that dire, but this study is a warning sign that we need to be careful with all of these new materials, and that they could dramatically change what’s happening in our environment.”

Carlson said the results of this study are unusual because typically when we talk about bacterial resistance it is because we’ve been treating the bacteria with antibiotics. The bacteria become resistant because we are trying to kill them, she said. In this case, the nanoparticles used in lithium ion batteries were never made to kill bacteria.

The research is published in Chemical Science, a peer-reviewed journal of the Royal Society of Chemistry.