In 2016, more than 2 million middle and high school students said they had used an e-cigarette in the last month, according to the Centers for Disease Control and Prevention, and among older teens and young adults, at least 40 percent of e-cig users said they had never been been regular cigarette smokers before starting.
Sales of vaping devices and e-cigarettes, which heat up nicotine-filled liquid into an aerosol that is then inhaled, have grown into a more than $8 billion per year worldwide behemoth, Bloomberg reported.
It isn’t difficult to speculate about why vaping has exploded in popularity.
E-liquid is relatively cheap, and the vapor generally doesn’t linger like smoke and bother others. The vapor is less irritating to the lungs and throat, and there is a seemingly endless buffet of flavors and nicotine strengths to choose from.
Those draws have made smoking e-cigarettes and other vaping devices attractive for young people who are turned off by tobacco, as well as for existing smokers looking for a way to keep the habit but ditch the health issues.
But a growing body of evidence is beginning to chip away at the idea that vaping is a safe alternative to smoking. Now a new study from Johns Hopkins University in Baltimore finds some e-cigarettes are leaking toxic heavy metals into the vapor users are inhaling.
In the study, scientists recruited 56 daily e-cigarette smokers from vape shops and vaping conventions around Baltimore. The researchers then asked to test the levels of toxic metals in the users’ e-liquid before it had been put into the device, the e-liquid in the storage tank of the device, and in the vapor that came out of the device.
They found that there wasn’t much to worry about with the e-liquid itself — there were only minimal levels of dangerous metals like lead, chromium, and nickel and manganese.
But when they tested the liquid in the storage chamber, as well as the vapor, they found much higher levels of toxic metals. The researchers say chronic exposure to the metals has been linked to lung, brain and heart damage, as well as cancer.
The culprits, the scientists think, are the heating coils that convert the e-liquid into a vapor to be inhaled.
The study backs up a previous one done by the same researchers back in 2017, which found heavy metals in several different brands of e-liquid — though at wildly inconsistent rates.
“One of the things that is troubling is that the metals in e-cigarette coils, which heat the liquid that creates the aerosol, are toxic when inhaled, so perhaps regulators might want to look into an alternative material for e-cigarette heating coils,” Ana María Rule, who led that study and the most recent one from Johns Hopkins, said in a release at the time.
The question is whether exposure to those toxic metals, at the level found in normal, everyday e-cigarette use, is dangerous.
The scientists in the most recent study say the median level of lead found in their sample was higher than the Environmental Protection Agency’s safety standard, and that levels of other metals such as nickel, chromium and manganese “approached or exceeded safe limits.”
But another analysis of previous studies on heavy metals in e-cigarettes published in 2015 concluded that, with normal use, levels of toxic metals are generally well below unsafe levels.
The scientists in the study concluded that exposure to heavy metals was not a significant health concern for people switching from tobacco to vaping, but was an “unnecessary source of exposure” for people who never smoked before.
The next step, Rule said in a release from Johns Hopkins, is to get to the bottom of whether these metals are harmful or not — and to present that data to regulators so they can make informed decisions.
“It’s important for the FDA, the e-cigarette companies and vapers themselves to know that these heating coils, as currently made, seem to be leaking toxic metals — which then get into the aerosols that vapers inhale,” Rule said in the release. “We’ve established with this study that there are exposures to these metals, which is the first step, but we need also to determine the actual health effects.”