# Would PG mist from vaping help to kill Coronavirus?



## Hooked (1/3/20)

*Would the PG mist from vaping help to reduce, deactivate, or kill some degree of airborne coronavirus?*
Chris Price, Expert patient, have also worked in hospitals on tech side.
https://www.quora.com/Would-the-PG-...of-airborne-coronavirus/answer/Chris-Price-69
28 Feb. 2020

"PG (propylene glycol) has been used and researched as an antimicrobial for 70+ years, since the 1940s. It has been well-demonstrated to be among the most effective airborne pathogen killers in existence, when dispersed as an aerosol. Note that it is an effective antibacterial and antiviral, when aerosolised (in mist form so to speak).

This is one of the 3 reasons it was used for decades as the water treatment agent in large buildings’ air-conditioning plant: (1) It kills airborne pathogens better than almost any other mist agent. (2) It has a very low freezing point, and therefore qualifies as an antifreeze agent in the water (thus, a typical glycol). (3) It is one of the non-toxic glycols: some are harmless (PG, PEG for example); some are toxic (e.g. DEG). PG and PEG have been used in medicines for decades; you will find PEG in many preparations, currently.

When PG was used as an aerosol / mist air treatment in hospital wards, it was found that it reduced both bacterial and viral airborne infections by 95%. Later it was shown that PG kills airborne pathogens when added to air at a concentration of 0.5ppm (i.e. 1 part per 2 million). I believe this extraordinary efficacy has never been fully explained.

*Legionnaire’s Disease*
When this became a serious issue, it was eventually found that poor (or zero) maintenance of the building’s aircon plant was responsible: the water/PG mix had not been changed, and had become contaminated over a number of years (or decades). Renewing the water and its treatment agent/s solved the problem.

Essentially this indicates that persons in large buildings breath in airborne particulate matter aerosolised from the aircon plant: they inhale water vapour and pathogens or PG molecules, depending on the state of maintenance of the aircon plant. No doubt this feature is well-understood in hospital maintenance schedules.

*Excipients*
PG was used for decades as the excipient (solvent, carrier) in inhalable medicines of all kinds, such as asthma inhalers, and for cyclosporine in post-op lung transplant patients; and for injectable medicines that are immiscible (cannot mix with water) such as diazepam. It is proven harmless for inhalation, injection and ingestion. There are minor intolerance issues (side effects), though more serious ones are infrequent.

Today it is still used for these purposes but at less frequency, other excipients have become popular. This is partly connected with PG’s main side-effect / intolerance issue: it is strongly hygroscopic (‘sucks out’ water), and dries the throat uncomfortably for some people when inhaled. In addition, a small number of people are subject to skin itching at high-dose levels of PG; some experience worsening of tinnitus, again when super-dosed (as in the older formats of vaping refills, which were typically PG-heavy).

Today most vape refills are based on glycerol (aka glycerine, VG) as this is more throat-friendly. The same process can be seen with inhalable medicines — see Dow Optim for example: a synthetic glycerol for inhalable medicines, now replacing other solvents.

PG is both bactericidal and virucidal (kills all pathogens); glycerol is bacteriostatic (may allow pathogens to exist, but not increase). Both are alcohols, as can be seen by the -ol suffix in glycol and glycerol. They are not drastically dissimilar chemicals as can be seen by a common version of their chemical names: propane 1,2 diol, and propane 2,3 triol.

PG has a similar effect to ethanol when ingested in large amounts: it causes intoxication, at about a 50% effect according to reports. It is otherwise safe to consume, which is why it is used as a pet-friendly winter antifreeze in RV and boat lavatories where a pet dog might be expected to lick the water. Cats however have a different blood chemistry from many other animals and will be harmed by large amounts of ingested PG, unlike humans and dogs. Thus PG can be used as a moisture retainer in dog food (and human food), but not in cat food.

*Personal experience*
My belief, from 10 years of experience with these compounds, is that a 2% inclusion of PG in a vape refill (the rest glycerol) is a useful but not aggressive addition, functioning as an antimicrobial as much as anything else (its original function, when vaping was invented by Chinese pharmacist Han Lee, was as the principle excipient).

It has been well-noted that the incidence of colds, flu, bronchitis and similar is significantly reduced in smokers who switch to vaping. Indeed some report complete freedom from infections even when previously afflicted, when smoking. It has not been possible to show which factor or factors is the effective agent here, due to the confounders present: inhalation of PG; cessation of smoke inhalation; or a combination of the two, for example. Certainly, smoking cessation and inhalation of PG does reduce or even eliminate infections from colds and flu; what causes this is disputed.

*Speculation*
It seems quite possible that a few drops of PG sprinkled on an otherwise less than effective cheap facemask might be better than nothing. This is after all the duty PG was put to for a long time. It can be bought at the local chemist as Propylene Glycol BP (in the UK, old style); or as Propylene Glycol EP (in the EU); or at the pharmacist/druggist as Propylene Glycol USP (in the USA).

It may be found that more liquids have to be sipped as a result, due to the throat drying effect some people experience. Fruit squash-type mixes such as blackcurrant juice in water are said to be useful."

Reactions: Like 1 | Winner 1 | Informative 3


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## Adephi (1/3/20)

Hooked said:


> Chris Price, Expert patient,



Question, what is an "Expert patient"?

Reactions: Like 3 | Agree 1


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## MrGSmokeFree (1/3/20)

Adephi said:


> Question, what is an "Expert patient"?


*" Expert patients* are *defined* as people living with a long-term health condition who are able to take more control over their health by understanding and managing their conditions, leading to an improved quality of life. Becoming an *expert patient* is empowering for people with chronic conditions."

Reactions: Like 4 | Winner 1 | Thanks 2 | Informative 4


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