Bogus Research on Formaldehyde in E-Cig Vapor

The New England Journal of Medicine yesterday published a letter claiming that vapor contains “hidden” formaldehyde at far higher levels than cigarettes (here), which made headlines worldwide.  That conflicts with a report I discussed last week, documenting that formaldehyde levels in e-cigarettes were far lower than those in traditional cigarettes (here).

R. Paul Jensen and colleagues at Portland State University produced the new results by overheating an e-cigarette, a condition (called dry puffing) that is familiar to vapers; the resulting product tastes so bad it cannot be inhaled.  In other words, the formaldehyde produced under abusive conditions is not “hidden” at all, because it is in vapor that users find intolerable.

Dr. Konstantinos Farsalinos, a cardiologist at the University of Patras in Greece and a recognized expert in vapor devices, has documented that the formaldehyde findings are bogus: “Lack of experience on e-cigarettes and no contact with vapers can result in such erroneous and unrealistic results, which can create confusion and misinformation both in the scientific community and among users and potential users of e-cigarettes… The authors of the NEJM study should have read our study and should have known about the existence of this phenomenon.” (here).

One of the new study’s authors, James Pankow, has published other scaremongering reports.  In 2010, he claimed that wintergreen flavor in smokeless tobacco is dangerous (here) and he coauthored a largely theoretical study claiming that “infants and children are particularly at risk” from thirdhand smoke. (here).

Modern automobiles have remarkably low pollutant emissions, but anyone behind a car that is overheating or otherwise abused can smell noxious fumes as they are released.  Using the New England Journal of Medicine, Jensen and colleagues have created global headlines with a defective e-cigarette experiment, producing scientific pollution.

Thirdhand Smoke Cancer Hysteria

The anti-tobacco extremists’ motto: if you can measure it, it must be deadly. Last week, a group of chemists and toxicologists published a largely theoretical study claiming that “infants and children are particularly at risk” from thirdhand smoke. The first author was Mohamad Sleiman; another, James Pankow, claimed several weeks ago that smokeless tobacco users were overdosing on wintergreen flavor.

The report appeared in the Proceedings of the National Academy of Sciences, a scientific journal that usually publishes solid research studies. Not this time.

Sleiman claims that nicotine residues in thirdhand smoke, which can become attached to skin, dust and items in houses or cars, can react with nitrous acid, which is formed by unvented combustion appliances (such as a gas cooktop) and smoking. The reaction produces NNK, which is a tobacco-specific nitrosamine (TSNA) that is considered a cancer-causing agent.

The report is largely theoretical, since it is very difficult to isolate and measure tiny levels of these chemical agents. For example, Sleiman estimated that smoking might expose human skin to as much as 15 nanograms of NNK per SQUARE METER. Keep in mind that a square meter is about 9 square feet. This is about 5 times the surface area of a normal adult. He also estimated that about 15 nanograms of NNK could be present over 9 square feet of furniture surfaces.

A nanogram is one billionth of a gram, and a gram is less than 4 hundredths of an ounce. So we are talking about vanishingly small amounts.

Sleiman didn’t discuss how infants and children could actually consume a 15 nanogram dose of NNK from that 9 square foot surface. He collected the residue by using special solvents, including methanol, so uptake by humans is likely to be very inefficient, perhaps negligible.

But let’s assume for a moment that a person is exposed to, and completely consumes, Sleiman’s dose of 15 nanograms of NNK every day for decades. What potential cancer-causing effect might this have?

The answer might come from what we know about NNK in a product used by millions of American men -- smokeless tobacco. In 2003, I published a study reporting the level of NNK in American moist snuff. I found that a typical 1-can per day user may be exposed to one thousand times more NNK, about 15-30 micrograms (actual consumption is probably far lower). Readers of this blog know that there is very little evidence that lifelong use of smokeless tobacco is associated with any cancer.

I am not the only tobacco researcher who is critical of the Sleiman study. Even Steven Hecht, a Minnesota professor who holds extreme positions with respect to smokeless tobacco, has doubts: “I personally feel that exposure by this route would be minimal…”

How harmful is thirdhand smoke? It probably carries about as much risk as third hand rain.