Studies show potential lower carcinogens in e-cig products
As the electronic cigarette industry, analysts and critics await definitive research on the health risks of e-cigs, studies released last week added to the smoke around the issue.
The main questions about e-cigs and vaporizers, which use open liquid capsules, continue to focus on their safety and what public-health role could they play in reducing the risk from consuming tobacco products.
A January 2015 letter published in the New England Journal of Medicine by scientists from Portland State University determined that excessively high levels of formaldehyde were produced by certain e-cigs and vaporizers, especially at high voltage/high temperature levels. They found little or no formaldehyde when the devices were used at low voltage.
Formaldehyde is classified as a carcinogen by the International Agency for Research of Cancer. It is believed to contribute to tobacco-related disease.
The Portland State researchers have said that while many e-cig smokers don’t use the product at such high-voltage levels, there are enough who do to warrant raising concerns of a higher lifetime risk of cancer than from traditional cigarettes.
Last week, two studies were released: one that sought comparisons to the Portland State study, and the other that compared the formaldehyde production of three e-cigs products with World Health Organization standards.
Anti-tobacco advocates seized on the Portland State study as proof that e-cigs were not only unsafe, but potentially less safe than traditional cigarettes, which produce carcinogens through the burning of the tobacco.
The Portland State study received sharp criticism from e-cigs advocates, who claimed most smokers would not use the product at such high levels because it requires taking a “dry puff” that typically contains an unpleasant taste.
“From the moment last year’s New England Journal of Medicine article came out, harm reduction advocates argued that the study suffered from severe methodological flaws,” said Gregory Conley, president of the American Vaping Association.
“In the face of clear evidence that the high levels of formaldehyde were only produced because the researchers had repeatedly burnt the coil inside the vapor product being studied, the authors of that study repeatedly declined to retract their paper. Even worse, the authors were awarded for their malfeasance with a $3.5 million grant from the Food and Drug Administration.”
Differences among products
The first new study was by Penn State University researchers and published in the March edition of Regulatory Toxicology and Pharmacology. It studied the effects on e-liquids by the voltage in e-cig devices.
What the researchers determined is that in three e-cig devices, there was an increase in total aldehyde yield with increasing power applied to the power coil, while two devices showed the opposite trend. The aerosol yields were set at 25 puffs.
“Formaldehyde and acrolein yields for one device exceeded both the yield from combustible cigarettes (20 per day) and the OSHA limit at the maximum power level tested,” the researchers said.
“However, three of the five devices studied yielded less formaldehyde, acetaldehyde and acrolein than delivered by combustible cigarettes.”
The researchers said their study “demonstrates that large differences exist in the electronic-cigarette devices available in the marketplace, and that, depending on the device, changes in power applied to the atomizer can have dramatic, but different, impacts on both total aerosol yield and the formation of aldehyde compounds in the electronic cigarette aerosol.”
No definitive answers
The second study was by British American Tobacco Ltd. researchers. It was made public at the Society for Research on Nicotine and Tobacco conference in Chicago.
What the BAT researchers determined is that formaldehyde is produced differently by traditional cigarettes and e-cigs/vaporizers. They tested the products at 350 puffs per day at high-voltage conditions expected to produce the most formaldehyde.
What they found is that formaldehyde production was 10 times less than that produced by a traditional cigarette.
“In cigarette smoke, most formaldehyde is produced as the result of burning sugars naturally present in tobacco, as well as added sugars and glycerol,” said Sandra Costigan, BAT’s principal toxicologist for e-cigs.
“Whereas in vaping products, it is generally produced as a thermal breakdown product of glycerol and propylene glycol.”
Studies conducted or sponsored by tobacco manufacturers tend to receive heightened scrutiny because of real or perceived conflict of interests with the use of their products.
Costigan acknowledges the study doesn’t provide definitive answers on how formaldehyde-releasing agents in e-cigs affect the body when inhaled.
Conley said the two new studies “show that when vapor products are used under realistic conditions, formaldehyde production is nonexistent or so low as to be comparable to the amounts that humans naturally exhale from their body every single day.”