Studies show tobacco heating system does not compromise indoor air quality

The use of tobacco heating system does not adversely affect the overall indoor air quality, according to several scientific studies published in peer-reviewed publications.

The studies were conducted to determine the impact on air quality of new nicotine products such as tobacco heating system (THS) which are considered better alternatives to combustible cigarettes. 

Researchers said assessing air quality is an important factor of the science behind products that heat and not burn tobacco as it provides a strong indication of the potential impact that a product’s use may have on bystanders.

A novel and smoke-free nicotine product, THS such as IQOS of Philip Morris International uses an electronically-controlled mechanism to precisely heat the specially-designed tobacco sticks at temperatures below the threshold for combustion or burning.

In a study published in September 2018 by ScienceDirect, the leading platform of peer-reviewed literature, researchers from Kaunas University of Technology in Lithuania reviewed the impact of THS on indoor air quality.

It compared the indoor concentrations of substances such as formaldehyde, acetaldehyde, benzene, toluene, nicotine and particulate matter 2.5 and discussed the concentrations of other harmful and potentially harmful substances.

"In the controlled environment, the use of THS (as well as an electronic cigarette) resulted in the lowest concentrations of formaldehyde, benzene, toluene, PM2.5 among majority researched pollution sources (conventional cigarettes, waterpipe, incense, mosquito coils)," according to authors Violeta Kauneliene, Marija Meisutovic-Akhtarieva and Dainius Martuzevicius.

"Such data indicate that the levels of the main indoor air pollution markers in case of THS environmental aerosol may be too low to distinguish from the background, thus raising additional challenges for epidemiological studies aiming at the assessments of second-hand exposure in real-life environments," they said.

Another study published on ScienceDirect in March 2018 found that emissions from THS are reduced in indoor air compared to those of conventional cigarettes. Researchers from British American Tobacco Investments Ltd. said THS has a significantly lower impact on indoor air quality than the conventional combustible cigarette because of significantly lower emissions profile of both aerosol particles and chemical emissions.

The study concluded that THS had significantly less impact on indoor air quality and that its emissions were significantly less odorous than those from conventional cigarettes and their emissions.

In 2017, the Ukrainian Journal of Modern Problems of Toxicology published a study by researchers from L.I. Medved's Research Center of Preventive Toxicology, Food and Chemical Safety, Ministry of Health of Ukraine which found that during THS use, substances such as benzo(a)pyrene, nicotine and ammonia were not detected.

"Contrary to conventional cigarettes, the actual content of the air safety indicators (carbon monoxide, carbon dioxide and formaldehyde) in indoor air during and after consumption of electrically heated tobacco system by no means exceeded the threshold limit value for atmospheric air," the Ukrainian study said.

A study published in April 2019 by SpringerLink, another global publication of peer-reviewed journals, assessed air quality of THS under simulated residential conditions.

Researchers led by Dr. Maya I. Mitova of Philip Morris International said that under simulated “Residential Category III” environmental conditions, only two compounds (nicotine and acetaldehyde) and one specific compound (aerosol former glycerin) were attributable to the indoor use of THS, but at below harmful levels.

"The quantified concentrations of the three airborne compounds during indoor use (of THS) in the high-load-simulated residential environment studies were below the harmful levels defined by cognizant authorities. Thus, normal hygienic measures, such as regular aeration of the residential spaces, would lead to efficient control of these low to negligible levels of pollution," they said.

The evaluation of the concentrations of particulate matter, volatile organic compounds and semi-volatile markers of environmental tobacco smoke during simulations also showed that the environmental aerosol of THS is very different from the smoke of combustible cigarettes.

"In conclusion, the use (of THS) in an indoor environment, where norms for indoor exposure in terms of adequate ventilation are respected, does not adversely affect the overall indoor air quality," the researchers said.