Perhaps you are reading the article with a bit of bias. The phrases of importance from the article are:
"Non-asthmatic volunteers (n=27)..."
"Propylene glycol may cause contact allergy, but there is sparse information on health effects from occupational exposure to PG."
"After exposure to PG mist for 1 minute tear film stability decreased, ocular and throat symptoms increased, forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC) was slightly reduced, and self rated severity of dyspnoea was slightly increased. No effect was found for nasal patency, vital capacity (VC), FVC, nasal symptoms, dermal symptoms, smell of solvent, or any systemic symptoms."
"In four subjects who reported development of irritative cough during exposure to PG, FEV1 was decreased by 5%, but FEV1 was unchanged among those who did not develop a cough"
"Short exposure to PG mist from artificial smoke generators may cause acute ocular and upper airway irritation in non-asthmatic subjects. A few may also react with cough and slight airway obstruction."
Reviewing the article (it was not a study, or genuine research of any kind), we note the following.
1) Sample size was crap. 27 people means nothing when your only qualifier is "non-asthmatic."
2) No double blind testing. No testing of other aerosols. No controls. This is why it's an article, and not a study.
3) Not related to intentional consumption of vaporized PG, but simply cited as a fog of PG.
4) Poor subject analysis. People suffering from allergies could "develop a cough," yet the article cites it as a link between irritation to PG and irritation of the throat. Specifically, they made the deduction, from a functionally non-existant sample size, that because other studies say women are more likely to be more sensitive to irritants their data shows more women were sensitive.
5) Bias. Read the discussion at the end of the article. They admit that the concentration is very high, and the exposure time is very low. Technically, I can get the same effect of throat irritation if I walk from a cold pool into a hot humid sauna.
This article is crap. The people quoting it are extrapolating data based on insufficient input information. There are plenty of "news" articles that cite it as a source that incontrovertibly proves PG should not be imbibed as an aerosol. Another cottage industry of fear mongerers has been built around nothing.
When you cite me a viable study that comes to the same conclusion I'll listen. Until then I assume that e-cigs are just about as bad as regular cigarettes. Any other assertion is either based in idiocy, or bending to propaganda. Neither option is reasonable.
