Life, gym, but not as we know it

Scientists have found antibiotic-resistant genetic material in the dust at athletic facilities, after machines and mats were wiped down using sanitiser that contained a chemical called triclosan.

The discovery adds to fears that routine hygiene practices are inadvertently cultivating antibiotic-resistant bacteria that pose a serious threat to human health. According to the U.S. Centres for Disease Control and Prevention, antibiotic-resistant infections kill at least 23,000 people each year in the United States.

Researchers led by Erica Hartmann of Northwestern University, Chicago, US, found a correlation between high concentrations of triclosan in dust and the occurrence of genetic markers indicating antibiotic resistance. Their work forms a study published in the journal mSystems. 

“Those genes do not code for resistance to triclosan,” Hartmann says. “They code for resistance to medically relevant antibiotic drugs.”

She and colleagues tested dust because it is made up of tiny particles of airborne detritus, broadly representing air quality. It also includes living organisms, such as bacteria, in which the team found the genetic mutations.

“There is this conventional wisdom that says everything that’s in dust is dead, but that’s not actually the case,” Hartmann explains. “There are things living in there,”

In 2017, triclosan was banned by the US Food and Drug Administration (FDA) from healthcare items, such as hand sanitiser, because of “a lack of sufficient safety and efficacy data”.

But the chemical can still be put in other items that aren’t under the FDA’s purview, such as “antibacterial” bedding, kitchen utensils and sports equipment. 

As Microban, the manufacturer and brand name for triclosan, says, the chemical can be put in everything from “cell phone cases to baby baths.” The company also says its newest technology is triclosan-free, but it is not immediately apparent which products no longer contain triclosan.

The researchers are conducting follow-up research to see if another antimicrobial, benzalkonium chloride, could also be promoting antibiotic-resistant organisms. 

“We don’t have solid proof that putting antimicrobials in these products makes them any healthier, but we do know that triclosan in the environment can be harmful,” Hartmann says.

Moreover, using antimicrobial products isn’t even necessary, she adds.

“The vast majority of microbes around us aren’t bad and may even be good,” she says.

“Wipe down gym equipment with a towel. Wash your hands with plain soap and water. There is absolutely no reason to use antibacterial cleansers and hand soaps.”