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Worldwide H1N1 Flu Pandemic? Is Propylene Glycol the answer? UPDATE... LINKS

Posted on 1st May 2009 @ 5:41 AM

Journal of Aerosol Medicine




Dr. Clayton Loosh was an Idahoan who attended the University of Chicago. He worked closely with Dr. O. H. Robertson. He was particularly helpful to the Commission in developing effective means of delivering virus in suspension for experimental challenges in human beings. He was also instrumental in developing the "glycolizers" that were used to create suspension of propylene glycol in the air. These were widely used at Camp Detrick for the protection of the staff who were working with particularly lethal agents. Later, after he became Dean of the School of Medicine at the University of Southern California, he continued to be an active participant in the affairs of the Commission. He worked with mice, trying to produce a controlled antigenic change in the virus. He also obtained interesting, and somewhat surprising, data on the effect of Los Angeles smog on mice infected with influenza virus. At one point, it appeared that the smog actually helped the animals, rather than hurt them. He was a very friendly person with broad interests who was exceptionally well qualified to be dean of a medical school.



The possibility of stopping the viruses in mid-air is of great interest. On this side of the Atlantic we have little concept of the importance of such a control, say in air-raid shelters where thousands of people have had to sleep night after night. In the British shelters the emphasis has been mainly on the control of cross-infections in operating rooms and in hospital wards. It has been found that small droplets such as are expelled in coughing can float in the air for many hours, even days. Arthur T. Edwards recently found that 10 percent of an original amount of influenza virus can remain alive on blankets for days or weeks. It is difficult to know whether the persistence of influenza in certain households is due to this domestication of the virus or to its constant introduction as active members of the family carry home the infection from outside contacts. It is the killing of these droplets that is urgently important. For this, two promising methods have been found: the use of ultraviolet light and of germicidal mists or aerosols.

The theory of their action is simply that a small amount of a chemical which is known to be germicidal be finely dispersed into the atmosphere. Water was not a satisfactory solvent, partly because of its rapid evaporation, and for that reason propylene glycol, a pretty name with which everyone will probably soon be familiar, was used to carry a number of germicides, including Dakin's solution. The English, hard-pressed to improve conditions in their air-raid shelters, which sometimes, as in Bristol, were in deep caves or old tunnels, used aerosols with evident success.

By the crab-like motion which characterizes so many scientific advances, it was then found that propylene glycol alone was highly effective. As little as one part of this substance, in the form of an aerosol, was active in at least several million volumes of air. Its effectiveness against both bacteria and viruses was established in this country by Oswald II. Robertson and his associates at the University of Chicago and later confirmed in England.



How did it work? Respiratory disease bacteria float about in tiny droplets of water breathed, sneezed and coughed from human beings. The germicidal glycol also floats in infinitesimally small particles. Calculations showed that if droplet had to hit droplet, it would take two to 200 hours for sterilization of sprayed air to take place. Since sterilization took place in seconds, Dr. Robertson concluded that the glycol droplets must give off gas molecules which dissolve in the water droplets and kill the germs within them.


Murray Laugesen

Public health physician  


That propylene glycol (PG) may protect users of the e-cigarette from airborne bacterial and viruses dates back to World War II. ‘Air Germicide’, a story in Time magazine Nov 16, 1942, reported the research of Dr. Oswald Hope Robertson at Chicago's BillingsHospital. He showed that half a part per million of PG in air could kill bacteria and viruses in that air within seconds. He found PG could protect mice from influenza virus, and that monkeys could well tolerate living in air containing PG. On the face of it, e-cigarette users might indeed be better off....actually confers immediate short term positive benefits, by reducing the risk of its users inhaling live viruses and bacteria from room air. This is mind-blowing enough, but could its possible benefits also protect others close by? Is the e-cigarette more than a tool for reducing harm? Is it also potentially a talisman to ward off infection? 

Protecting air travelers 

Air travel is a weak point in defending ourselves internationally from fatal respiratory infections. Bird flu and pandemic influenza can spread globally at the speed of jet travel, as one infected person can infect many others through air-conditioned, re-circulated air. Governments are spending millions on how to contain or just even slow the spread of such epidemics. Perhaps PG should be seriously considered. 


Studies completed by Dr. Oswald Hope Robertson of University of Chicago's Billings Hospital have shown propylene glycol inhalation may prevent pneumonia, influenza and other respiratory diseases. Time Magazine - Air Germicide

Cases of propylene glycol poisoning are related to either inappropriate intravenous use or accidental ingestion by children.[6] The oral toxicity of propylene glycol is very low. In one study, rats were provided with feed containing as much as 5% PG over a period of 104 weeks and they showed no apparent ill effects.[7] Because of its low chronic oral toxicity, propylene glycol is generally recognized as safe (GRAS) for use as a direct food additive.

Serious toxicity will occur only at extremely high intakes over a relatively short period of time that result in plasma concentrations of over 4 g/L.[8] Such levels of ingestion would not be possible when consuming reasonable amounts of a food product or dietary supplements containing at most 1 g/kg propylene glycol.


Dr. Robertson's laboratory then undertook a double program of field studies in hospitals, army barracks, and industrial installations and laboratory experiments in an effort to develop methods of combating the spread of air-borne infections, which had become an exceedingly important source of attrition of human effectiveness during the war. Studies were carried out on the physical chemistry of aerosols containing viable infectious agents. Effects of various parameters on the viability of these agents were studied and the mechanism of air sterilization by chemical agents was worked out in detail. Such studies showed that the previously held theory that bactericidal action was exerted through collision of aerosol particles of germicide with aerosol particles of the infectious agent was erroneous, and that the actual mechanism of action required action of the bactericidal agent through the vapor phase. New agents were developed which were enormously more effective than previous materials, and which were shown to be without toxic effects to human populations. The physical chemistry of aerosol vapor interactions was studied, and a number of fundamental papers were published in this field. While the use of chemical air sterilization was developed to the point where it became a practical measure, it never proved possible to obtain clear-cut epidemiological data demonstrating beyond any question that these measures would reduce respiratory disease in ordinary situations of human habitation. Nevertheless, the fundamental advances obtained in the course of these studies have been useful in a variety of ways, in both pure and applied science.