Now, researchers from the University of Georgia are looking at how environmental factors could play a role in antibiotic resistance. According to their findings, pollution could increase the incidence of antibiotic resistance nationwide.
“The overuse of antibiotics in the environment adds additional selection pressure on microorganisms that accelerates their ability to resist multiple classes of antibiotics,” said researcher Jesse C. Thomas IV. “But antibiotics aren’t the only source of selection pressure. Many bacteria possess genes that simultaneously work on multiple compounds that would be toxic to the cell, and this includes metals.”
To understand how pollution can affect antibiotic resistance, the researchers analyzed soil samples from four spots in South Carolina. They evaluated the genetic make-up of the soil in order to determine any present bacteria that could be resistant to antibiotics.
The researchers also paid particularly close attention to the effect of metals in the samples, as heavy metals aren’t biodegradable. This means that the effects of such contamination can last indefinitely. Ultimately, the team learned that the soil samples that were most contaminated by heavy metals were the most likely to contain antibiotic resistant bacteria.
The study also revealed that there was a great deal of overlap between antibiotic-resistant genes and metal-resistant genes within the samples. This is important because heavy metals are often associated with antibiotic resistance, so this likely amplifies the resistance to traditional treatment methods.
Specifically, the researchers found that these soil samples resisted the powers of three commonly used antibiotics that are used to treat infections: polymyxin, vancomycin, and bacitracin.
Though the researchers plan to do more research on the relationship between metal resistance and antibiotic resistance, these findings are important because they can help identify how actions associated with pollution can contribute to antibiotic resistance.
“We need a better understanding of how bacteria are evolving over time,” said Thomas. “This can impact our drinking water and our food and eventually our health.”