Melissa
Kaplan's
Herp Care Collection
Last updated
January 1, 2014
Antibacterial Products May Fuel Growth of Superbugs
Jaqueline Stenson, ReutersHealth, 9/30/2002
Triclosan is found in a variety of soaps, household cleaners, toothpastes, baby toys, sponges and other products.
But questions have emerged as to whether these products are doing more harm than good.
In the latest research, Stanford University investigators conducted laboratory studies involving triclosan and a variety of strains of the E. coli bacterium. They found that some E. coli strains that were resistant to triclosan became increasingly hardy over time.
"The results from the experiment indicate that constant exposure to triclosan can cause bacteria to tolerate it better and become more and more resistant," said study author Clara Davis, a PhD student.
"This increased level of resistance can also be accompanied by an increased (bacterial) growth rate," said Davis, whose findings were released here Saturday at a meeting of the American Society for Microbiology.
This latter finding is unusual, she said, because bacteria that develop resistance to an antibiotic or other antibacterial agent generally grow more slowly than bacteria that are sensitive to the agent, she explained. From a public-health standpoint, this is beneficial because when the antibacterial agent is not present, the drug-sensitive strain may grow to dominate the drug-resistant strain.
But the new research suggests that E. coli bacteria that are resistant to triclosan may continue to persist, even thrive, whether triclosan is present or not.
The results raise questions of how well triclosan may continue to work in the future, Davis said.
"Just as the antibiotics used to treat infections do not always work due to bacterial resistance, our results imply that resistance (to triclosan) could arise in a bacterial population and persist," she said.
Studies are needed to understand how these laboratory findings apply to a home environment where triclosan products are used, Davis added.
One industry representative agreed that bacterial resistance to triclosan in the lab may not reflect that occurring in the home.
"Although a few laboratory studies have found evidence of bacterial resistance under very specific experimental conditions, review of the available information leads to the conclusion that triclosan does not induce nor selects for resistance against antibiotics used for the therapy of human diseases under actual use or "real-life" conditions," according to Keith A. Hostetler, a spokesperson from Ciba Specialty Chemicals, a manufacturer of triclosan.
