Replication study: Flavored e-cig aldehyde emissions are ‘589-fold lower’ than ACS claims
Back in November of 2016, the American Chemical Society (ACS) published a paper claiming that certain e-liquid flavorings are enormously high in multiple toxic aldehydes. The vaping industry immediately and overwhelmingly rebuked the study. Meanwhile, many scientists began to accuse the study’s co-authors of either following poor scientific procedures in the laboratory or intentionally manipulating the data to conform to a pre-determined, anti-vaping conclusion.
Dr. Konstantinos Farsalinos immediately took to his blog about ten days after the study’s publication to openly refute its findings. The study entitled Flavoring Compounds Dominate Toxic Aldehyde Production during E-Cigarette Vaping Is published by the ACS, but its co-authors Andrey Khlystov and Vera Samburova are from the Department of Atmospheric Sciences at the Desert Research Institute (DRI) in Reno, Nevada. The resulting paper is available or review in the journal Environmental Science and Technology.
The basis of the DRI experiment involved the evaluation of e-cig vapor produced from multiple different flavors of e-liquids while comparing their aldehyde levels to those of unflavored e-juice. Remarkably, the DRI team reported that the unflavored e-liquids produced no aldehyde emissions whatsoever while the vape juices made with coffee, watermelon, and blueberry flavorings were over 10,000 times higher comparatively. According to Farsalinos, these findings are simply not credible.
Dr. Farsalinos claims that these statistics are essentially impossible to achieve, even if the heating temperatures of the related vaping device were somehow manipulated to abnormally high levels. This has occurred in many previous anti-vaping studies, most specifically regarding one paper which notoriously claimed that e-cig vapor is laced with formaldehyde. The problem with the recent DRI/ACS report lies not in its statistics related to the flavored e-liquids but those associated with the plain varieties.
“The problem with this study is that the results contradict previous research on aldehyde emissions. A large number of studies have shown that aldehydes are formed due to thermal degradation of the main ingredients of e-liquids, namely propylene glycol and glycerol. Even more importantly, John Lauterbach reported in a 2015 conference that radiolabeled aldehydes were found in the aerosol of e-liquids containing radiolabeled PG and VG... This is definite proof that, at least part of, aldehydes are formed due to thermal degradation of the humectants of e-liquids. I cannot explain why the authors found no aldehydes (i.e. below LOQ) in the unflavored liquid.”
Since the zero-aldehyde levels of the non-flavored e-liquid vapor are obviously wrong, then those associated with the flavored e-liquids must be as well. The entire study is essentially bogus, but just to be sure, Dr. F decided to replicate the study in his own laboratory.
Result of the Farsalinos replication study
Just yesterday, Dr. Farsalinos published the results of his replication study entitled Do flavouring compounds contribute to aldehyde emissions in e-cigarettes? on the Science Direct website. He and his research team determined that the aldehyde emissions of the three flavors of e-liquids-in-question are significantly “lower by up to 589-fold” than those reported by the ACS.
“Low levels of formaldehyde (8.3–62 μg/g), acetaldehyde (12.1–26.0 μg/g) and acrolein (5.4–19.4 μg/g) were detected, lower by up to 589-fold compared to the previous report. Unflavoured liquid emitted 16.1 mg/g formaldehyde, 5.6 μg/g acetaldehyde and 2.4 μg/g acrolein, significantly lower compared to 2 liquids for formaldehyde and 1 for acrolein. Emissions from the new-generation device were even lower. Aldehyde emissions from all flavoured liquids were 79–99.8% lower than smoking and lower than commonly measured indoor levels and occupational and indoor safety limits.”
This is not the first time that Dr. Konstantinos Farsalinos of the Onassis Cardiac Surgery Center in Greece has come to the rescue of the global vaping community. He has also recently refuted the findings of a Johns Hopkins study which claimed that e-cig vapor is high in arsenic and other trace metals. He has also previously claimed that this surge in bogus research is essentially “academic McCarthyism” – an implied form of anti-vaping propaganda disguised as allegedly reputable, but intentionally manipulated, scientific “evidence.”