Thursday, December 26, 2013

Do E-Cigarettes Cause Passive Vaping?

“Passive smoking” has been hotly contested. Is there a case for “passive vaping”?  Hardly.

A detailed study of e-cigarette vapor by German investigators at the Fraunhofer Wilhelm-Klauditz-Institute’s Department of Material Analysis and Indoor Chemistry detected virtually no quantifiable levels of 20 volatile organic compounds (VOCs) present in cigarette smoke (abstract here).

They had a volunteer smoker puff three e-cigarette liquids and one combustible cigarette in a cramped test chamber measuring about 6 feet cubed.  The volunteer took six, deep 3-second puffs on each item at one-minute intervals; air samples were taken for 15 minutes after the fourth puff.

These are the results for the 20 agents with the highest concentrations. 

Concentrations (ug/m3) of Volatile Organic Compounds (VOCs) in Vapor From Three E-cigarette (Average) and Smoke From a Cigarette
VOCE-cigarette VaporCigarette Smoke
Propylene glycol*112
1-hydroxy-2-propanone *62
Acetic acid1368

*Unquantifiable/same as empty chamber

Five VOCs were detected in e-cigarette vapor at minuscule levels.  The level of formaldehyde was similar to that measured before the e-cigarette puffs, leading the investigators to comment that it “…might be caused by the person in the chamber itself, because people are known to exhale formaldehyde in low amounts.”  Acetone and acetaldehyde may have resulted from combustion of propylene glycol during e-cigarette puffing, which also occurs to a larger extent during smoking.  Propylene glycol, a major component of vapor, was not present in the chamber during-after e-cigarette use. 

Although the investigators aimed to identify VOCs “under near-to-real-use conditions to estimate the effect of ‘passive vaping,’” the use of a 6 foot cubed chamber is not real-world.  They answered their title question, “Does E-cigarette Consumption Cause Passive Vaping?” in the affirmative, but these barely measurable results, extrapolated to rooms of normal size, confirm that bystanders have virtually nothing to worry about from vapers.

Wednesday, December 18, 2013

Legacy Tells the Truth – Tobacco Harm Reduction Revolution Gains Momentum

After 20 years of staunch opposition to and misinformation about tobacco harm reduction from anti-tobacco forces, one prominent figure has broken ranks, offering the truth and a cautious endorsement of safer tobacco products. 

David B. Abrams, PhD, Executive Director at American Legacy Foundation’s Schroeder Institute for Tobacco Research and Policy Studies (here), recently acknowledged in a college newspaper (here) that smoke-free tobacco products are vastly safer than smoking.  Here is the key passage from that article:

“Though he said that there is not much research on e-cigarettes, Abrams said the studies he has seen ‘put e-cigarettes in the category of somewhere between nicotine replacement therapy, which is pharmacy-grade nicotine from a pharmacy, and smokeless tobacco products, which are not harmless but are also much less harmful than cigarettes.’  He said that in terms of risk, he would slot e-cigarettes between snus — a type of powdered tobacco — and dissolvable nicotine products.”

Coming from an executive at one of the most anti-harm-reduction organizations, this is a revolutionary statement.  As readers of this blog know, numerous published epidemiologic studies document that American and Swedish smokeless tobacco products have disease risks so low that they cannot be measured with any precision.  Dr. Abrams’ risk assessment for e-cigarettes is therefore accurate.

This was the second time in two weeks that Dr. Abrams acknowledged the substantial risk differential between combusted and smoke-free tobacco.  On November 25, he commented at a Wells Fargo e-cigarette forum in New York:

“[E-cigarettes are] dramatically less and probably in the order of 10 to 100 times less dangerous than combusted cigarettes.  And certainly even less harmful than the data I've seen for
smokeless tobacco, although they're also dramatically less harmful than cigarettes.  So I'd say they're somewhere in between the ‘safest nicotine replacement pharmaceuticals’ and smokeless. And I would regard smokeless as a decent harm reduction strategy along with e-cigarettes in the map of harm reduction versus quit or die total abstinence.” 

Thus far, the campaign to inform smokers about safer products has been led by a handful of tobacco research and policy experts (here).  Dr. Abrams’ statements should pressure harm reduction deniers to abandon their failed quit-or-die mantra and start telling smokers the truth about safer cigarette substitutes.  This underscores my view that the tobacco harm reduction revolution is unstoppable.

Wednesday, December 11, 2013

The CDC Abuses the Facts About E-Cigarettes – Part II

In a previous post (here), I noted false and misleading information in a U.S. Centers for Disease Control and Prevention press release about e-cigarette use by youth. 

The CDC reported that 76.3% of youth using an e-cigarette in the past 30 days had also smoked at least once in the same period, and it used that number to suggest that e-cigarettes are a gateway to youth smoking.  First, there is no evidence in the dataset to support that claim.  Second, the CDC didn’t report survey information on other tobacco products.  Only about 10% of vapers were not concurrent users of any tobacco product, and only about 5% had no past history of smoking. 

Here, I’ll present other important facts that the CDC didn’t share about youth vapers who were questioned in the 2012 National Youth Tobacco Survey (NYTS).

The NYTS is a comprehensive survey of youth tobacco use, attitudes and perceptions; it contains a lot of e-cigarette information that the CDC failed to report.  I analyzed a number of questions relative to use of both cigarettes and e-cigarettes, comparing smokers who had also vaped in the past 30 days (smoker-vapers) with those who had not (exclusive smokers).  The results, summarized in the table below, illustrate differences (all of which are statistically significant – p< 0.05) between the two groups.

Here are the relevant NYTS questions and answers for smoker-vapers and exclusive smokers: 

Question 12.  About how many cigarettes have you smoked in your entire life?  Sixty-four percent of smoker-vapers had consumed over 5 packs of cigarettes, compared with 39% of exclusive smokers. 

Question 13.  During the past 30 days, on how many days did you smoke cigarettes?  Fifty-one percent of smoker-vapers reported smoking on 20 days or more, compared with 29% of exclusive smokers. 

Question 14.  During the past 30 days, on the days you smoked, how many cigarettes did you smoke per day?  Thirty-one percent of smoker-vapers consumed 6 or more cigarettes, versus 18% of exclusive smokers.

Question 57.  Are you seriously thinking about quitting cigarettes?  Forty-one percent of smoker-vapers said they were not seriously thinking about quitting, compared with 28% of exclusive smokers. 

Question 58.  If you decided to quit cigarettes for good, how likely is it that you would succeed?  Thirty-two percent of smoker-vapers labeled themselves as somewhat or very unlikely to succeed, compared with only 17% of exclusive smokers. 

There was another insightful survey item:

Question 69.  Do you believe that electronic cigarettes or e-cigarettes…are (less harmful, equally harmful, or more harmful) than regular cigarettes?  Seventy-two percent of smoker-vapers correctly answered that e-cigarettes were less harmful, and 51% of exclusive smokers also got it right.  These are impressive numbers, given that tobacco opponents uniformly insist that “we don’t yet understand the long-term effects of these novel tobacco products,” as FDA tobacco center chief Mitch Zeller said in the CDC press release (here). 

This post is not a comprehensive analysis of the 2012 NYTS findings on e-cigarettes.  My purpose is to report some interesting findings that the CDC failed to mention in their PR campaign to portray e-cigarettes as a teenage scourge.

Federal officials should fully and accurately report the results of taxpayer-funded research.  Americans – including teenagers – deserve the truth about e-cigarettes.

Percentage of Smoker-Vapers and Exclusive Smokers With Answers to Selected Questions, NYTS 2012
Question=AnswerSmoker-VapersExclusive Smokers
Cigarettes smoked, entire life= 5+ packs69%39%
Days past month smoked= 20+51%29%
Cigarettes on days smoked= 6+31%18%
Seriously thinking about quitting cigarettes= No41%28%
Successful quitting= somewhat or very unlikely32%17%
E-cigarettes less harmful than cigarettes72%51%

Wednesday, December 4, 2013

The CDC Abuses the Facts About E-Cigarettes – Part I

The headline on the Centers for Disease Control’s September 5 press release was dire: “E-cigarette use more than doubles among U.S. middle and high school students from 2011-2012” (here).  The agency’s shocker generated reams of coverage (examples include USA Today, the Los Angeles Times, the Chicago Tribune and CBS News).

In an earlier blog post, I criticized the CDC’s media ploy for positioning e-cigarettes as a new childhood tobacco epidemic (here).  Based on additional research, I have uncovered serious flaws in the agency’s analysis – errors and omissions that made the CDC’s message more appealing to the media, but less conscionable in terms of public health.

Analyzing the 2012 National Youth Tobacco Survey (NYTS), the dataset the CDC used to generate its report, I discovered the falsehood of this key statement in the agency’s press release:  “Altogether, in 2012 more than 1.78 million middle and high school students nationwide had tried e-cigarettes.”  This assertion was highlighted in most major media reports.

In fact, the NYTS did not collect information on the number of students who had used e-cigarettes in 2012.  Instead, the survey asked if students HAD EVER TRIED e-cigarettes, “even just one time”; that number is 1.78 million.  The only number in the survey that is applicable to 2012 is the 554,179 students who used an e-cigarette on “at least one day” in the past month.  That is only 31% of the number wrongly reported by the CDC.

Another statement in the CDC release is seriously misleading: “The study also found that 76.3 percent of middle and high school students who used e-cigarettes within the past 30 days also smoked conventional cigarettes in the same period.”  That statement implies that 24% of e-cigarette users were not smokers, and gives the distinct impression that e-cigarettes are emerging as a first-use tobacco product.

Not so fast.  The NYTS also measured other forms of tobacco use, including smokeless tobacco, cigars, pipes, hookah, snus and dissolvable tobacco.  In addition to the 76.3% of e-cig users who were concurrent cigarette smokers, another 12.9% were using other tobacco products.  That means the percentage of e-cigarette users who weren’t using any other tobacco product was only 10.8%, a tiny fraction.  Of this group, about half had “ever tried cigarette smoking, even one or two puffs”. 

There is another feature of this and other federal surveys that you need to understand: the numbers that the CDC reports (e.g. 1.78 million) are not actual counts but are national estimates based on a complex sampling strategy.  This is not necessarily a problem, but it provides needed context, especially when the number of survey respondents is small.  For example, the total number of youths in this survey who used an e-cigarette in the past 30 days was 500, and the number of vapers who did not use any tobacco product nor had ever tried smoking was around 20.

The bottom line: Among all middle and high school e-cigarette users, only 10.8% were not concurrently using any other tobacco product, and half of those had tried to smoke in the past. 

CDC director Tom Frieden may wish to use his position as a bully pulpit to oppose e-cigarette use, but abusing the facts is inexcusable.

In a future post I’ll discuss other key findings from the NYTS that were omitted by the CDC.