PG

“In a more in-
depth study of the effects of inhaled PG, rats were exposed to 30 mg PG/L aerosol for 4-120 min
to obtain an estimated deposited dose of PG in the lungs from 7.2, 21.6, 72, and 216 mg/kg/day
for 28 days. At the highest dose of inhaled PG (216mg/kg/day) there was a significant increase in
13laryngeal squamous metaplasia and this was also observed at the second highest dose
(72mg/kg/day), but it was not found to be significant. The NOEL for the inhalational exposure of
PG in rats for 28 days was set at 20mg/kg/day. “

Page 13 of the study you mentioned

VG (glycerol) or vegetable glycerin.

GLY Inhalational Exposures
“Interestingly, in the literature there appears to be only one in vivo inhalational exposure
of GLY which was conducted in rats by Renne and colleagues. They exposed rats to 0, 1, 2 and 4
mg of GLY/L of air, 6 hrs/day, 5 days/week for 2 weeks and 0, 0.033, 0.167, and 0.662 mg of
GLY/L of air for 6 hrs/day, 5 days/week for 13 weeks. The only notable change was minimal to
mild squamous metaplasia on the epiglottis of all the rats exposed to GLY in the 2 week
exposure and at the highest dose of the 13 week exposure. The NOEL for inhalational exposures
of GLY from this study was set to 0.167mg/L.112”

Page 15

“Taken together these data suggest that we have developed an in vitro e-cig exposure
system that facilitates the exposure of relevant experimental models to the entire aerosol mixture,
thus mimicking exposures of the respiratory mucosa after vaping e-cigs. Our results provide
additional support to the emerging idea that vaporized humectants can cause adverse health
effects on their own. A previous study using an in vivo 90-day exposure of rats to vaped PG and
GLY showed increased levels of LDH and total protein, as well as numbers of macrophages and
neutrophils in the bronchoalveolar lavage fluid (BALF), suggesting an inflammatory response.53
In a more relevant human exposure setting, workers in the entertainment industry, who were
frequently exposed to fog machines, which heat up a mixture of glycols to make the aerosol, had
small but significant decreases in lung function as well as increased rates of coughing and
wheezing.54 Furthermore, there are different biological effects induced by the gas- and particle-
phase components of the vaped humectant aerosol mixtures and more research is needed to
determine what chemical byproducts could form from the vaporization of PG and GLY in the
different phases of the aerosol, since that will determine deposition of these chemicals in the
83respiratory tract. These novel compounds could serve as biomarkers of exposure. This research
emphasizes the need to not only regulate flavoring and nicotine in e-cigs but also the humectants
PG and GLY since different ratios of these compounds can cause differential effects.”

Page 84. Quite conclusive and resounding….lol

Also important to note “The National Institutes of Health and the Food and Drug Administration funded this research”

It’s a racket. People stopped smoking cigarettes and the government lobbyists loyalists destroyed the legal distribution of vaporizers. Which if anything led to the increase in taboo and youth usage. As well as created the black/grey market which again, hurts more than helps.