August 12, 2014

Stanton A. Glantz, PhD

Indoor air expert publishes risk assessment of e-cigarettes

In the June 2014 issue of ASHRAE Journal, Bud Offerman, an expert on indoor air published a well-done risk assessment of active and passive exposure to e-cigarette aerosol using standard methods.  (ASHRAE is the American Society for Heating, Refrigeration, and Air Conditioning Engineering, the organization that develops engineering standards for, among other things, building ventilation systems.  The tobacco companies spent years keeping ASHRAE from identifying secondhand smoke as a serious indoor air pollutant, something ASHRAE eventually did.)
 
Here are the first and last paragraphs of Offerman's paper:

The prevalence of the use of e-cigarettes is increasing. E-cigarettes are marketed as an alternative to smoking tobacco that only produces harmless water vapor, with no adverse impact on indoor air quality. However, published literature seems to show that e-cigarettes are not harmless. Photo 1 shows an e-cigarette user exhaling a dense visible aerosol into the surrounding air. This visible aerosol consists of condensed submicron liquid droplets, which contain many chemicals including some that are carcinogenic, such as formaldehyde, metals (cadmium, lead, nickel), and nitrosamines.

 

We conclude that e-cigarettes emit harmful chemicals into the air and need to be regulated in the same manner as tobacco smoking. There is evidence that nitrosamines, a group of carcinogens found specifically in tobacco, are carried over into the e-cigarette fluid from the nicotine extraction process. There is also evidence that the glycol carriers can by oxidized by the heating elements used in e-cigarettes to vaporize the liquids, creating aldehydes such as formaldehyde.  Consumers should be warned that, while the health risks associated with the usage of e-cigarettes are less than those associated with tobacco smoking, there remain substantial health risks associated with the use of e-cigarettes.
 

This paper almost certainly underestimates the risks because it only considers the chemicals in the aerosol, not the untrafine particle, which have important adverse effects.
 
The full paper is available here.

Comments

Comment: 

Is this a peer reviewed publication?-I dont think so!

Comment: 

<strong;A study by ASHRAE verifies the safety profile of e-cigarettes, but authors fail to admit it.</strong;
&nbsp;
<em;By Dr Farsalinos&nbsp; </em;http://www.ecigarette-research.com/web/index.php/2013-04-07-09-50-07/201...
There are a lot of discussions in the social media about a&nbsp;http://bookstore.ashrae.biz/journal/download.php?file=2014June_038-047_I... theAmerican Society for Heating, Refrigeration, and Air Conditioning Engineering&nbsp;(ASHRAE) concerning e-cigarette safety. The study was published in ASHRAE Journal, and obviously it was not peer-reviewed. Several methodological mistakes have been found in this paper, which need to be clarified. In reality, the paper verifies that e-cigarettes are by far less harmful that tobacco cigarettes, but the authors fail to admit it and make erroneous conclusions and suggestions.
The authors made some crucial mistakes in their methodology. As a result, they do not present the “worst-case scenario”, but an unrealistic scenario. Firstly, they assume that 100% of the vapor that is inhaled gets absorbed by the user. Obviously, this is far from true, since a substantial proportion of vapor is exhaled by the user. Surprisingly, to assess the impact of environmental exposure, they assume the exact opposite: that 100% of the vapor is exhaled by the user!! They go even further by assuming that this vapor (which is released to the environment is 100% absorbed by the bystanders. It is more than obvious that these assumptions are completely wrong and would not stand any serious peer-reviewing.
Moreover, the authors use the data from http://tobaccocontrol.bmj.com/content/23/2/133.abstract";Goniewicz et al, but considered only the maximum values found in those experiments. This is a major methodological mistake. Moreover, I wonder why they did not assess environmental exposure by using http://www.ncbi.nlm.nih.gov/pubmed/24336346";another paper which measured exactly that. The most probable reason for not using that study is because the authors mentioned: “<em;The study showed that e-cigarettes are a source of secondhand exposure to nicotine but not to combustion toxicants.</em;”
Even if we ignore all these methodological issues, still the findings support that e-cigarettes are by far less harmful than tobacco cigarettes. They mention the cancer risk from exposure to nitrosamines, ignoring that the levels found in tobacco cigarettes are up to http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4110871/";1800 times higher. For heavy metals, I present data from the US Pharmacopeia about the daily maximum permissible daily exposure of heavy metals from medications (based on a 50kg person).
&nbsp;
<img alt="" src="http://www.ecigarette-research.com/web/images/heavy%20metals4.jpg" border="0" /;
&nbsp;
For lead, the permissible levels are similar to what you would get from 1315 e-cigarette puffs, for cadmium 1022 puffs and for nickel 775 puffs (even if we assume 100% absorption, which of course is wrong). The levels found in e-cigarettes may pose some residual risk, but it is by far lower compared to tobacco cigarettes.
&nbsp;
This is another study which verifies that e-cigarettes are by far less toxic compared to tobacco cigarette. The authors’ conclusions about the risk from e-cigarette use, and their suggestion to impose similar regulations to tobacco cigarettes, are completely arbitrary, inappropriate and unsupported by their own data (which were calculated by making unrealistic assumptions).
&nbsp;

Comment: 

The following are my reponses to the criticisms by Dr. Farsalinos of my paper in the ASHRAE Journal "The Hazards of E-Cigarettes". I have embraced the text of my responses with ***.
&nbsp;
There are a lot of discussions in the social media about a publication by the American Society for Heating, Refrigeration, and Air Conditioning Engineering&nbsp;(ASHRAE) concerning e-cigarette safety. The study was published in ASHRAE Journal, and obviously it was not peer-reviewed.
&nbsp;
*** The ASHRAE Journal article is directly from the peer-reviewed paper that I recently presented in Hong Kong at Indoor Air 2014 (Offermann F (2014)&nbsp;Chemical Emissions from E-Cigarettes: Direct and Indirect Passive Exposures, Indoor Air 2014&nbsp;Conference Proceedings, July 7-12, 2014, Hong Kong). ***&nbsp;
&nbsp;
Several methodological mistakes have been found in this paper, which need to be clarified. In reality, the paper verifies that e-cigarettes are by far less harmful that tobacco cigarettes, but the authors fail to admit it and make erroneous conclusions and suggestions.
&nbsp;
*** The title of Dr. Farsalinos’s blog<strong; </strong;“A study by ASHRAE verifies the safety profile of e-cigarettes, but authors fail to admit it”, implies that e-cigarettes are safe.
Dr. Farsalinos should know better, and I suspect he probably does, but my paper does NOT provide evidence that e-cigarettes are safe, nor did I attempt a comparative risk assessment between use of e-cigarettes and tobacco-based cigarettes. To proclaim that e-cigarettes are “far less harmful”, a comprehensive study would require assessment of ALL the very many chemicals emitted by e-cigarettes, and my paper only discusses the hazard assessment associated with just nine of the chemicals emitted by e-cigarettes.
In my paper I do state that e-cigarettes are less harmful (how less is unknown) then tobacco-based cigarettes, but still represent a substantial health risk:&nbsp; “Consumers should be warned that, while the health risks associated with the usage of e-cigarettes are less than those associated with tobacco smoking, there remain substantial health risks associated with the use of e-cigarettes.” ***
&nbsp;
The authors made some crucial mistakes in their methodology. As a result, they do not present the “worst-case scenario”, but an unrealistic scenario. Firstly, they assume that 100% of the vapor that is inhaled gets absorbed by the user. Obviously, this is far from true, since a substantial proportion of vapor is exhaled by the user. Surprisingly, to assess the impact of environmental exposure, they assume the exact opposite: that 100% of the vapor is exhaled by the user!! They go even further by assuming that this vapor (which is released to the environment is 100% absorbed by the bystanders. It is more than obvious that these assumptions are completely wrong and would not stand any serious peer-reviewing.
&nbsp;
*** I was very clear in the assumptions made for the hazard assessment that I conducted for second hand (passive) exposure to the chemicals emitted by e-cigarettes. For this assessment I did select model inputs that represent what I considered to be a “worst-case” exposure scenario. This exposure scenario was not unrealistic and not intended to represent the average or population weighted exposure.
With respect to the vapor (actually an aerosol of submicron liquid droplets containing glycols, nicotine, and other chemicals, including carcinogens such as formaldehyde), the percentage of vapor exhaled depends upon the how deep the vapor is inhaled and how long the vapor is retained in the respiratory system before being exhaled. For those e-cigarettes users that just puff and do not inhale deeply into their lungs, the percentage of vapor exhaled will be close to 100%, and thus a reasonable assumption for a worst-case exposure scenario.
With respect to the vapor inhaled by the “bystanders”, since the air inhaled does enter deep into the lungs and into the alveoli, where there is a large surface to volume ratio, a high percentage of the sub-micron particles will be retained. More importantly, while the cancer exposure hazard analyses (i.e. NSRL) requires knowing the dose to the individual, and hence the fraction of the inhaled contaminants retained by the respiratory system, the non-cancer exposure hazard analyses (i.e., CREL), are not based on dose but simply on exposure and thus do not require knowledge of the respiratory system retention of the contaminants, as this is already built into the exposure guidelines. ***
&nbsp;
Moreover, the authors use the data from Goniewicz et al, but considered only the maximum values found in those experiments. This is a major methodological mistake.
&nbsp;
*** Not at all a mistake, rather my selection of the maximum chemical emission rates from the Goniewicz study is consistent with the study objective which was to examine the worst-case exposures and not the average or population weighted exposures. However, if we do compare the chemical emissions from all 12 brands of e-cigarettes studied by Goniewicz (and for propylene glycol and nicotine the 3 brands studied by Schripp), we in fact find that the emissions exceed the exposure guidelines for more than just the one brand with the highest chemical emission rates. For acrolein, a potent irritant, the direct exposure exceeds the CREL for 6 of the 12 brands, and for formaldehyde, another potent irritant (and carcinogen), the direct exposure exceeds the NSRL for 5 of the 12 brands. And for nicotine, and propylene glycol, both the direct and indirect (passive) exposures exceed the CREL for each of the 3 brands studied by Schripp.
Thus, the exposure guideline exceedences reported in my paper are not just limited to a single brand of e-cigarettes with the highest reported chemical emissions, but rather extend across multiple brands. ***
&nbsp;
Moreover, I wonder why they did not assess environmental exposure by usieg another paper which measured exactly that. The most probable reason for not using that study is because the authors mentioned: “<em;The study showed that e-cigarettes are a source of secondhand exposure to nicotine but not to combustion toxicants.</em;”
&nbsp;
*** While Dr. Farsalinos fails to cite this “another paper”, having familiarized myself with all of the e-cigarette chemical emission rate studies in scientific peer-reviewed literature, I am unaware of such a study that shows that e-cigarettes are NOT a source of “combustion toxicants”. Indeed e-cigarettes, while not combustion devices, have been shown to emit chemicals that are created by combustion, such as aldehydes, including formaldehyde, though the creation is by thermal oxidation of the heated glycols and not actual combustion. ***&nbsp; &nbsp;
&nbsp;
Even if we ignore all these methodological issues, still the findings support that e-cigarettes are by far less harmful than tobacco cigarettes. They mention the cancer risk from exposure to nitrosamines, ignoring that the levels found in tobacco cigarettes are up to 1800 times higher.
&nbsp;
*** Yes, the exposure to NNK is indeed less for e-cigarettes, but this is by far insufficient data to conclude that e-cigarettes are “far less harmful” than tobacco smoking. Yes, as I have concluded in my paper, e-cigarettes do present less of a health risk than tobacco smoking, but how much less, has not yet been determined. Such a comparison would require a comprehensive comparison of ALL of the chemicals emitted by e-cigarettes and tobacco-based cigarettes, and the health risk associated with the combined chemical exposures, according to target organ, for each product. Such a study has not been done to date and is required before one can opine on how much less health risk is associated with e-cigarettes (so e–cigarette industry, you need to do the research to quantitatively demonstrate the health risk associated with your product). This much is known, e-cigarettes do pose a significant health risk to both users and non-users. ***
&nbsp;
For heavy metals, I present data from the US Pharmacopeia about the daily maximum permissible daily exposure of heavy metals from medications (based on a 50kg person).
&nbsp;
For lead, the permissible levels are similar to what you would get from 1315 e-cigarette puffs, for cadmium 1022 puffs and for nickel 775 puffs (even if we assume 100% absorption, which of course is wrong). The levels found in e-cigarettes may pose some residual risk, but it is by far lower compared to tobacco cigarettes.
&nbsp;
*** I am not sure why Dr. Farsalinos utilizes for his calculations the USP PDEs, which are recommendations promulgated by pharmaceutical companies for metal impurities in drugs, but I believe the more relevant exposure guidelines for e-cigarettes are the NSRL exposure guidelines for cancer that I used in my hazard assessment, [OEHHA (Office of Environmental Health Hazard Assessment) (2013) Proposition 65 Safe Harbor Levels. No Significant Risk Levels for Carcinogens and Maximum Allowable Dose Levels for Chemicals Causing Reproductive Toxicity.] If you use the NSRL exposure guidelines, then the number of puffs per day required to exceed the daily maximum exposure guideline is just 35 puffs/day for cadmium and 135 puffs/day for lead, each of which is less than the median of 175 puffs/day for e-cigarette users. ***
&nbsp;
This is another study which verifies that e-cigarettes are by far less toxic compared to tobacco cigarette.
&nbsp;
*** My comments above address why the studies conducted to date preclude any quantitative assessment as to how much less toxic e-cigarettes are than tobacco cigarettes.***
&nbsp;
The authors’ conclusions about the risk from e-cigarette use, and their suggestion to impose similar regulations to tobacco cigarettes, are completely arbitrary, inappropriate and unsupported by their own data (which were calculated by making unrealistic assumptions).
&nbsp;
*** “Arbitrary, inappropriate and unsupported by their own data” ? I believe our hazard assessment leaves us with absolutely no other conclusion than that stated in our paper, “We conclude that e-cigarettes emit harmful chemicals into the air and need to be regulated in the same manner as tobacco smoking<strong;.” </strong;
To help further adoption of such regulations for e-cigarettes, on May 1, 2014 I submitted a proposed change to ASHRAE Standard 62.1, “Ventilation for Acceptable Indoor air Quality”. The proposed change adopts the same environmental tobacco smoke (ETS) requirements in 62.1-2013 and extends these to the burning or vaporization of substances, including herbs, cannabis (now legalized in two states), and e-cigarette fluids. This proposed change was accepted by the 62.1 committee at their summer meeting this June in Seattle and hopefully will be headed for a speedy public review and publication.
Hopefully history will not be repeated, where from 1994 to 1997 as a member of ASHRAE 62, I struggled for an addendum to the standard that would remove from the table of ventilation rate requirements, the footnote “accommodates a moderate amount of tobacco smoking”. It was only until I sent an Emergency Action Standard Request to the president of ASHRAE, the first in the history of the society, that an addenda “e” was incorporated into 62-1999, and tobacco smoking was finally determined to not be accommodated by ventilation.
&nbsp;
Let’s hope that lessons learned back then are remembered and ASHRAE will show the leadership we expect and quickly adopt my proposed change.***

Comment: 

You failed to see that in Dr Farsalono's comment the mention "another paper" had a link to the "another paper". Here's the link for you: http://www.ncbi.nlm.nih.gov/pubmed/24336346" title="http://www.ncbi.nlm.nih.gov/pubmed/24336346";http://www.ncbi.nlm.nih.gov...

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