Tobacco companies readily declare that a hip-looking 20-something puffing away on a sweet-flavored, smokeless "e-cigarette" is a health-savvy smoker who is avoiding the dangers of tobacco cigarettes while enjoying the smoking experience.
Electronic cigarettes, on the market in the U.S. for about five years, provide nicotine from a heated and vaporized fluid, doing away with the harmful byproducts of burned tobacco.
But the health risks from e-cigarettes remain largely unknown. Research is scant, and the new products' safety is far from certain. UC Riverside cell biologist Prue Talbot has found that some fluids used to refill e-cigarettes are toxic to cells.
Her lab also found that the performance of different smoking devices varied significantly and often required stronger puffs to activate than conventional cigarettes. This potentially could draw harmful chemicals deeper into the lungs.
Studying chemicals for health risks
Talbot now leads a major study of the chemicals contained in new versions of the e-cigarettes, and their health risks. The early research and the new studies are funded by the UC Tobacco-Related Disease Research Program.
The research demonstrates the need for a better understanding of these products, she said.
"Our earlier studies with electronic cigarette refill fluids showed that some of these products were toxic to both mouse neural stem cells, [and] human embryonic stem cells as well as to adult lung cells," she said. And at least some e-cigarette components may threaten developing fetuses in mothers, as regular tobacco cigarettes do, and also may damage lung tissue.
In a second round of studies, Talbot's team has dissected "cartomizers" — devices used in newer versions of e-cigarettes that combine both the flavored fluid and the battery-powered heater in a single unit. The researchers have found that when heated, the aerosol from one brand of cartomizer-style cigarette contained 21 elements, including a number of metals and metal nanoparticles. One metal, tin, appeared to be released from solder joints in the cartomizers.
"We need to know more about the full range of chemicals delivered by e-cigarettes, as well as their concentrations and their long-term effects on health," Talbot said. This would provide a solid basis for FDA regulations of e-cigarettes that both electronic cigarette companies and e-cigarette users probably would find beneficial.
Flavored smokes appeal to youth
Promoted as a safe alternative to tobacco products or as a way to taper off of a regular smoking habit, e-cigarettes are being aggressively marketed toward young people, said Pamela Ling, a UCSF associate professor of medicine who has conducted research supported by UC's Tobacco-Related Disease Research Program.
Fruit, candy and alcohol-flavored tobacco cigarettes are banned, Ling said. The only flavor exception is mentholated cigarettes. In contrast, e-cigarettes are offered in hundreds of flavors.
"They are being offered in fruit and candy flavors, and even tobacco-flavored products are given odd names like ‘bombshell,' which evokes a feminine image," said Ling, who studies the marketing of tobacco products to vulnerable groups. "Earlier studies of cigarette marketing showed that flavored cigarettes have their greatest appeal to young people."
Even though tobacco companies cannot promote conventional tobacco cigarettes on television, she says, we now are seeing TV ads for e-cigarettes. The TV and Internet images may subliminally promote tobacco cigarettes.
"If you look at the ads showing people smoking e-cigarettes, they look very much like they are smoking conventional cigarettes," Ling said.
"While there have been no studies specifically on the e-cigarette commercials, this type of advertising should not be allowed, because the 2012 Surgeon General concluded that advertising causes kids to smoke, and that exposure to smoking in movies causes kids to start smoking."
Ling says that research is "desperately needed" to determine if the vaporized fluid and other components of e-cigarettes pose health risks, since they already are being aggressively marketed as safe. In addition, e-cigarette manufacturers and advocates are flooding the FDA with comments on the safety of e-cigarettes "with little research to back up their claims."
Meanwhile, in Talbot's lab, her team is carrying out studies on various brands and models of e-cigarettes to determine what concentration of cartridge fluid and aerosol are harmful to cultured cells. They also use analytical chemistry to identify and measure the concentrations of chemicals in the fluids and aerosols, and determine what concentrations are toxic to the cells.
The pioneering research tests the toxicity in cell types that model the effects on both adult smokers and on fetuses in pregnant women.
"We hope that this research will help establish the safety of this new product and protect health of young people and adults," said Talbot.