A new study finds e-cigarette vapors may contain potentially unsafe levels of toxic metals, including lead and arsenic.
Researchers from Johns Hopkins Bloomberg School of Public Health tested e-liquids in the refilling dispensers of 56 daily e-cigarette users both before and after vaping, as well as the aerosols users inhale.
They found small amounts of some toxic metals in the liquids before use, but much higher levels were detected after the liquids had been exposed to the device’s heating coils.
Coils may leak toxic metals
A “significant” number of devices produced aerosols with potentially dangerous levels of lead, chromium, manganese and/or nickel, the researchers found. Aerosol metal concentrations were highest for e-cigarette users with more frequently changed coils.
Although the study was small, the authors say its findings are important and warrant evaluation by the Food and Drug Administration (FDA) due to the potential health consequences of exposure to these metals.
The FDA does not currently regulate e-cigarettes but has the authority to do so, the study authors noted.
"It's important for the FDA, 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," said senior study author Ana Maria Rule of the Bloomberg School in a statement.
Chronic exposure to metals such as those found in the study have been linked to negative effects on the lungs, brain, heart, liver, and immune system. These metals have also been linked to cancer.
The researchers note that the toxic metals found in aerosols were “often much higher than safe limits.” The aerosol is created after an electric current produced by a battery passes through a metal coil, which then heats nicotine-based liquids.
The fact that minimal levels of metals were found in the e-liquids within the refilling dispensers, but levels 25 times higher were found in aerosols, led the researchers to believe the heating coils may increase the metal concentration.
The source of the lead “remains a mystery,” but e-cigarette heating coils typically contain nickel and chromium, among other elements, the researchers pointed out.
"We don't know yet whether metals are chemically leaching from the coil or vaporizing when it's heated," Rule said.
The full study has been published online in the journal Environmental Health Perspectives.