Vegetable Glycerin, or glycerol is a substance that’s derived from the fats of animals and plants and is phosphorylated by glycerol-3-kinase to develop into glycerol-3-phosphate.
The metabolism of the glycerin takes part in the liver (about 80%), but can also be found in other cells, as it is a standard component of the cell metabolism. The glycerin is converted into glucose. Its toxicity is low when it comes to a broad range of animals and humans. A healthy person can tolerate 2.2g/kg of glycerin for 50 days with no side effects at all.
Because of the relatively low exposure from vaporization devices, it happens that just the respiratory glycerin exposure is classified as a risk.
About the glycerin vapor inhalation
The mechanics of the electronic glycerin vaporization gadgets
When it comes to vaporization gadgets, about 80% of glycerin mixture is heated to a minimum of 132 degrees Celcius. The combination of negative pressure (from inhalation) heat and turbulent airflow will cause the vaporization and the aerosolization of the liquid. The glycerin vapor makes its appearance when you inhale and exhale, and it comes out as the “puff”, which lasts from 1 to three seconds. Remember that, between every puff, there is something called inter-puff interval, that lasts from 15 seconds to 60 seconds, time period when the ambient air which gets inhaled contains little glycerin in comparison to the concentration of the puff. This happens because of the gas diffusion mechanics and the small volume of gas from the expanding of the lung into the larger volume of the environment of the consumer.
Animal Studies
There’ve been some studies about long-term inhalation, which showed absolutely no proof of toxicity of 0.165mg/L and 0.033mg/L glycerol in rats. However, irritation was seen at 0.662mg/ when the glycerol vapor exposure was continuous for 6 hours every day. The thing is that this not seems to be a real case for humans.
Human Studies
NIOSH, or The National Institute for Occupational Safety and Health, and OSHA, or Occupational Health Safety and Health Administration have decided on an acceptable exposure limit for aerosolized glycerin - 5mg/m3 and 10mg/m3 for the total exposure and the respiratory exposure. The accepted limit of 5mg/m3 is advisable for the exposure of over 8 hours in a working day.
Studies have proved that an inhalant vaporization gadget can produce a glycerol concentration of 300-500mg/m3 from one single puff, which is actually above the limit of 5mg/m3 put by the NIOSH.
With all of these in mind, it’s good to know that the exposure in a vaporization gadget is limited to the 1 to 3 seconds continuation of every puff, thing that is followed by a 15 to 60 (it usually takes 23 seconds) period of time, in which the glycerin concentration lowers with the respiration.
Rasel Khan is an internet entrepreneur