Cigarettes May Contain Bacteria
Study Shows Cigarettes May Be Contaminated With Hundreds of Types of Bacteria
WebMD News Archive
Nov. 24, 2009 -- Cigarettes are massive germ factories that may expose users
and passersby to a swarm of disease-causing bacteria, a study shows.
It's well known that cigarette smoke harbors hundreds of toxic chemicals
that are bad for your health. But a University of Maryland environmental health
researcher says that's not the only danger. DNA examination of four cigarette
brands shows, for the first time, that cigarettes are "widely contaminated"
with hundreds of different types of bacteria. In fact, there appears to be as
many bacteria in cigarettes as there are chemicals.
"The commercially available cigarettes that we tested were chock full of
bacteria, as we had hypothesized, but we didn't think we'd find so many that
are infectious in humans," says researcher Amy R. Sapkota, an assistant
professor in the University of Maryland's School of Public Health.
Sapkota and microbial ecologists at the Ecole Centrale de Lyon in France
examined the bacteria content in four major cigarette brands: Camel, Kool
Filter Kings, Lucky Strike Original Red, and Marlboro Red and found similar
types of bacteria in each one.
Previous research has watched for bacterial growth in lab dishes containing
small tobacco samples, but this study is the first to scrutinize a cigarette's
bacterial genetic makeup.
The testing revealed that cigarettes contain a wide variety of bacteria that
are linked to lung, blood, and food-borne-related infections. Among those
Acinetobacter -- associated with certain blood and lung
Bacillus -- some types are associated with anthrax and food
Burkholderia -- some strains can cause respiratory infections
Clostridium -- linked to food poisoning-related illnesses and lung
Klebsiella -- associated with many kinds of lung, blood, and other
Pseudomonas aeruginosa -- a specific type of bacteria that is
responsible for 10% of hospital-acquired infections
"If these organisms can survive the smoking process -- and we believe they
can -- then they could possibly go on to contribute to both infectious and
chronic illnesses in both smokers and individuals who are exposed to
environmental tobacco smoke," Sapkota says.
Although the public health implications of these findings are unclear at
present, scientists plan to continue their research to determine if the
bacteria can be implicated in tobacco-related diseases. A big question is
whether or not cigarette-borne bacteria can survive the burning process and
enter the lungs of smokers and grow. Some evidence suggests that some bacteria
can spread this way. The bacteria may also be present on, or in, the
The study findings appear online ahead of print in the journal
Environmental Health Perspectives.