Smoking out microbes

From Washington, D.C., at a meeting of the American Society for Microbiology

Nicotine, the compound that so satisfies smokers, is also a potent killer of bacteria. In test-tube studies, it can destroy more than a dozen types of bacteria, including ones that cause diseases, Saleh A. Naser of the University of Central Florida in Orlando reports.

He and his colleagues observed that nicotine, at concentrations much less than those in the saliva of people who smoke regularly, readily destroys a wide range of bacteria. Germs that cause tuberculosis, as well as gum and skin diseases, were all susceptible. So were bacteria that naturally reside on human skin and in people’s mouths and gastrointestinal tracts.

Naser speculates that the reason smokers are prone to gum disease is that the nicotine from their cigarettes eliminates protective microbes that normally ward off disease-causing bacteria that even the nicotine can’t check.

It isn’t clear how nicotine kills bacteria, but researchers looking to keep microbes at bay still might exploit smokers’ favorite compound. “It has the potential to be used as a disinfectant,” Naser asserts.


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