I don't understand where traces of formaldehyde on exhale comes from.
Perhaps some from the participants' own natural exhaled breath.
Excerpts from the National Cancer Institute Fact Sheet
Formaldehyde and Cancer Risk - National Cancer Institute
"Formaldehyde also occurs naturally in the environment. It is produced in small amounts by most living organisms as part of normal metabolic processes."
"According to a 1997 report by the U.S. Consumer Product Safety Commission, formaldehyde is normally present in both indoor and outdoor air at low levels, usually less than 0.03 parts of formaldehyde per million parts of air (ppm). Materials containing formaldehyde can release formaldehyde gas or vapor into the air. One source of formaldehyde exposure in the air is automobile tailpipe emissions."
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And from PubMed:
Experimental setup and analytical methods for... [.... Chim Acta. 2010] - PubMed - NCBI
.... Chim Acta. 2010 Jun 11;669(1-2):53-62. doi: 10.1016/j.aca.2010.04.049. Epub 2010 May 18.
Experimental setup and analytical methods for the non-invasive determination of volatile organic compounds, formaldehyde and NOx in exhaled human breath.
Riess U, Tegtbur U, Fauck C, Fuhrmann F, Markewitz D, Salthammer T.
Hannover Medical School, Sports Physiology and Sports Medicine, Carl-Neuberg-Str. 1, 30625 Hannover, Germany.
Abstract
Different analytical
devices were tested and evaluated for their suitability of breath gas analysis by examining the physiological parameters and chemical substances in the exhaled breath of ten healthy probands during light cycling in dependence of methanol-rich nutrition. The probands exercised under normal breathing conditions on a bicycle ergometer. Breath air was exhaled into a glass cylinder and collected under steady-state conditions. Non-invasively measured parameters were pulse rate, breath frequency, temperature, relative humidity, NO(x), total volatile organic compounds (TVOC(PAS)), carbon dioxide (CO(2)), formaldehyde, methanol, acetaldehyde, acetone, isoprene and volatile organic compounds (VOCs). Methanol rich food and beverages strongly influenced the concentration of methanol and other organic substances in human breath. On the other hand, nutrition and smoking had no clear effect on the physical conditions of the probands. The proton transfer reaction mass spectrometry (PTR-MS) method was found to be very suitable for the analysis of breath gas but the m/z 31, if assigned to formaldehyde, is sensitive to interferences. The time vs. concentration curves of nitric oxide showed sudden peaks up to 120ppb in most of the measurements. In one case a strong interference of the NO(x) signal was observed. The time resolved analysis of exhaled breath gas is of high capability and significance for different applications
if reliable analytical techniques are used. Some compounds like nitric oxide (NO), methanol, different VOCs as well as sum parameters like TVOC(PAS) are especially suitable as markers. Formaldehyde, which is rapidly metabolized in the human body, could be measured reliably as a trace component by the acetylacetone (acac) method but not by PTR-MS.
Copyright 2010 Elsevier B.V. All rights reserved.
PMID: 20510903 [PubMed - indexed for MEDLINE]
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Bold emphasis mine)
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From Anti-THR (
tobacco harm reduction) Lies and related topics:
The passive vaping fable | Anti-THR Lies and related topics
Two excerpts from: "The passive vaping fable"
Posted on 5 September 2012 by Elaine Keller | 8 Comments
posted by Elaine Keller (with input from Carl V Phillips)
"Take the case of the paper published by German researchers on the subject of chemicals in electronic cigarette (e-cigarette) vapor.
Schripp T, Markewitz D, Uhde E, Salthammer T. Does e-cigarette consumption cause passive vaping? Indoor Air. 2012 Jun 2."
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Keller wrote:
"
Just how hazardous are the compounds in vapor? The Occupational Safety and Health Administration publishes permissible exposure limits (PELs) for hundreds of chemicals that might be present in the air at workplaces. Five of the six compounds were present in quantities that are less than 1% of the PEL. The sixth compound, formaldehyde, is produced naturally by the human body, and it was present at 2.4% of the PEL. If the researchers had provided this comparison in their data, it would have been obvious that their conclusions did not fit the facts."
