Many people think electronic cigarettes are a safer alternative to tobacco cigarettes, but a new study suggests that's not the case.
In laboratory experiments on cultured cells, researchers from the University of California, Los Angeles, found that toxic substances and nanoparticles in e-cigarette vapours caused 85 percent of the tested cells to die.
They said it's possible these substances can kill the top layer of skin cells in the oral cavity. The oral cavity is the portion of the mouth behind the teeth and gums.
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The researchers believe that similar results would be found in tests on people, and said they're planning a human study to confirm their findings. If confirmed, the researchers said that e-cigarettes could increase users' risk of oral disease.
"A small but significant portion of dental patients at UCLA Dental Clinics have used e-cigarettes, which will provide sufficient patient resources for our planned studies," said study author Shen Hu, an associate professor of oral biology and medicine at UCLA's School of Dentistry.
There has been a large increase in e-cigarette use in recent years. The researchers noted significant increases among women and young people.
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About 2.4 million middle and high school students in the United States were using e-cigarettes in 2014, according to the US Centres for Disease Control and Prevention.
Health care providers need to do more to raise public awareness about the health risks of e-cigarettes, the study authors said.
"Our hope is to develop a screening model to help predict toxicity levels of e-cigarette products, so that consumers are better informed," explained Hu in a university news release.
The study was published online recently in the journal PLoS One.
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