Prue Talbot, a professor of cell biology at UCR, clears the air regarding the latest take on an old vice.
By Vickie Chang
People have been puffing tobacco for a long time — about 2,000 years, to be exact — but only recently did the world truly learn about its adverse effects: lung cancer, secondhand smoke, addiction, environmental impacts and more.
“If you look at the usage of tobacco cigarettes in the United States, the curve starts to go up around 1900 and it escalates,” said Prue Talbot, a professor of cell biology in the Department of Cell Biology Neuroscience and the director of the UCR Stem Cell Center and Core. “If you look at the incidence of lung cancer, that curve follows tobacco cigarette usage by about 20 years.”
In fact, Talbot said, there was very little lung cancer before people began smoking tobacco cigarettes. As their popularity grew, so did the disease.
“One doesn’t smoke a cigarette and get cancer the next week,” Talbot says. “Because it takes about 20 years for the cancer to develop, it took a while to get good data showing the correlation between smoking and lung cancer.”
In the same way, electronic cigarettes are creating their own uncharted territory, she said.
“We have to be very careful with electronic cigarettes and track them to see if anything develops that we are not anticipating right now.”
Invented in 2003 by a Chinese pharmacist, e-cigarettes were patented internationally in 2007. They go by a few names: e-cig, personal vaporizer (or PV), vape or electronic nicotine delivery system (ENDS), but the term itself — electronic cigarettes — is actually a general term.
They come in many types and shapes and have evolved greatly over the last decade, from the original “ciga-lites,” which mimicked the look of traditional tobacco cigarettes, to the cartomizer cigarette, containing both a battery and a cartomizer. The cartomizer holds the fluid and the atomizing unit, which heats the fluid to create vapor. Today’s larger tank models don’t necessarily resemble cigarettes. They contain a larger battery with a tank that holds more fluid, reducing the refill rate.
These liquids normally contain propylene glycol, glycerin, water, nicotine and “e-juices” — flavorings such as gummy bear, strawberry shortcake and doughnut. It’s these sweet flavors that are attracting some negative attention to the e-cigarette industry, with critics arguing that these juices are designed to attract underage users.
Talbot, who has worked at UCR for more than 30 years, started researching issues surrounding e-cigarettes when they were introduced in the Riverside area around 2009.
“My lab has been working on tobacco-related diseases for over 20 years … but when e-cigarettes came out, we were immediately interested in them,” she said. “They looked like a very intriguing new product that may have a lot of impact in the tobacco world … and there was virtually no information in the literature on them at that time.”
Safer? Maybe not
Here are seven e-cigarette myths that Talbot and her lab are investigating
All e-cigarette liquid refill flavors, sometimes called “e-juice,” are created equal.
Not necessarily. Talbot screened the cytotoxicity (the quality of being toxic to cells) of refill fluids and found that some were highly toxic.
“The one that was the most cytotoxic — we tested three different cell types and it killed all three — was a flavor called Cinnamon Ceylon. We hypothesized that there was something more toxic about cinnamon flavors than others.”
After purchasing various cinnamon flavors from different vendors, Talbot concluded that while the levels ranged, cinnamon flavors in general had some toxicity to them. All of them contained a chemical called cinnamaldehyde, which gives cinnamon its flavor.
“The amounts vary depending on the product, but the higher the concentration of cinnamaldehyde, the more toxic the product was,” Talbot said. “We felt that some vendors were probably putting way too much of this chemical, cinnamaldehyde, into their products and it was making them dangerous.”
As it turns out, users on e-cigarette discussion boards were also discussing cinnamon flavors and discouraging their use, because of side effects such as sore throats and coughing.
E-cigarette manufacturing is regulated by the federal government.
Sorry — not yet.
In fact, one particular study by Monique Williams, a graduate student working under Talbot, came after she noticed large, visible pellets of tin in the fluid extracted from certain e-cigarettes.
It turns out, one particular brand of e-cigarettes was producing large pellets of tin from poor-quality soldered joints holding the wires together.
“And apparently, in the pretesting that was done before sale, there were cycles of heating and cooling (where) the tin-soldered joints had melted or fallen apart. That contributed to loose tin particles in the fluid, which could get into the aerosol. So we started looking more carefully at what elements might be in the aerosol,” Talbot said.
This project is currently ongoing in Talbot’s lab. “There is no information on what the long-term health effects of inhaling tin this way would be,” Talbot said, “but we do know from other studies on tin dust that it can cause lung problems.”
It’s important to note that not all e-cigarettes produce large amounts of tin in their aerosol. “But, of course, the user would not know if they were using a cigarette that was producing tin or not,” Talbot said. “Most e-cigarettes are made in China and the companies that make them range from very small, family-owned shops to larger companies. There is no regulation on how they’re manufactured.”
E-cigarettes simply produce water vapor and not any dangerous chemicals.
False! This particular myth seems to be disappearing, but e-cigarettes actually do emit chemicals.
“When people smoke real tobacco cigarettes, they’re burning tobacco, which generates thousands of chemicals (and) many of those chemicals are known to be dangerous,” Talbot said. “E-cigarettes produce an aerosol that contains a number of chemicals, but not as many as tobacco-burning cigarettes.”
However, as Talbot points out, it would only take a single bad chemical to make e-cigarettes more harmful than tobacco cigarettes.
E-cigarettes don’t cause the same environmental concerns as traditional cigarettes.
False! The negative effects of cigarette butt waste are well known (countries like Australia have even established fines for improper disposal) but there isn’t that much information yet on the consequences of e-cigarette waste, and Talbot feels the risk could be considerable.
“A lot of these [e-cigarette] products are now disposable; the user uses them once and then throws them out,” Talbot said. “The discarded e-cigarettes include both a battery and residual fluid containing nicotine … so this is something that really needs to be addressed.”
People use e-cigarettes the same way they use traditional cigarettes.
False! Electronic-cigarette users tend to take longer puffs than tobacco smokers, according to research in Talbot’s lab.
The study was first conducted using videos found on YouTube of people smoking e-cigarettes.
“We found that electronic cigarette users had a bit longer puff duration than the 2-second puff typical of tobacco cigarette smokers. When we did the YouTube study, most e-cigarette users were taking puffs 4 seconds in duration,” Talbot said.
Her lab then took the study further, enlisting the help of 20 electronic-cigarette users and studying their individual puff patterns.
The users had their own unique style for puffing e-cigarettes, “as we expected,” Talbot said, “but they did take a puff every 18 seconds, which is more frequent than what we would usually see with a traditional cigarette smoker. When they puffed an e-cigarette for 10 minutes, the total puff volume was actually a lot larger than it would be for a regular cigarette.”
We don’t have to worry about secondhand smoke when it comes to e-cigarettes.
First, e-cigarettes don’t actually produce what we know as secondhand smoke, Talbot said.
The burning end of tobacco cigarettes is constantly releasing something called side-stream smoke. The person who is actually smoking the cigarette is exhaling. Secondhand smoke is a combination of the exhale and what’s burning off the cigarette.
Secondhand tobacco smoke has been shown to cause health problems to those constantly exposed to it. But there hasn’t been much research about the effects of exhales from e-cigarettes, Talbot said.
“The electronic cigarette does not have anything burning off the end of it, so that side-stream smoke is not emitted from an e-cigarette — which would probably make it considerably safer,” she said.
“But the individual who is using the e-cigarette is still exhaling aerosol. We have been working with several people who have contacted us because they were being passively exposed to e-cigarette exhaled residue and they felt that passive exposure was making them ill.”
Talbot says more work needs to be done on the topic. Her lab is working on research that shows exhaled aerosol from a vape shop can travel through the air vents in a building to other shops where people could potentially be exposed.
E-cigarettes are simply less harmful than tobacco-burning cigarettes.
The short answer? We just don’t know yet.
“There isn’t enough information to know,” Talbot said. “People just haven’t used e-cigarettes long enough.”