Before we go into depth on the subject matter at hand, we need to start by saying that inhaling anything other than oxygen is not safe. If you do not already have a dependency on nicotine, you should not be using any e-cigarettes or heat-not-burn products. These products are designed to present an alternative to existing smokers and are not intended to be used by people who are not already consuming nicotine.
With that being said, we can now explore some of the scientific studies conducted on the IQOS and other heat-not-burn products. To quickly summarize what each article says, these products are considered to be less harmful than traditional cigarettes. While this may seem like a potentially damaging risk to some users, these types of products are still an alternative to traditional cigarettes and based on studies conducted by Public Health England (PHE) and the Committee on Toxicity, heat-not-burn products have been found to contain fewer chemicals when compared to smoking.
Evidence review of e-cigarettes and heated tobacco products 2018 – Public Health England (PHE) (2018)
As part of PHE’s 2018 study on e-cigarettes, the British health group also investigated the effects of heated tobacco products (heat-not-burn) devices. In the studies, PHE’s core objective was to “review the existing peer-reviewed evidence on emissions and use of current heated tobacco products and to supplement this with recent evidence from UK surveys.”
Of the 843 records identified in PHE’s initial search, 19 studies were included in the review, seven of these were funded independently of the tobacco industry, eleven were funded by the manufacturer of IQOS (Philip Morris International), and one study was funded by a competing tobacco company.
According to the numerous studies included in PHE’s report, the mainstream smoke (the aerosol inhaled directly by the user) contained lower amounts of nicotine when compared to cigarette smoke, though this was still more nicotine than a cigalike e-cigarette and less than a tank-style e-cigarette. Researchers also noted that heated tobacco products reduced urges to smoke and exposed users and bystanders to lower levels of particulate matter and potentially harmful compounds.
Toxicological evaluation of novel heat-not-burn tobacco products – non-technical summary – Committee on Toxicity (2017)
Completed with support from the COC and the COM, this evaluation was conducted to assess the toxicological risks of heat-not-burn products, compared to the risks posed by conventional cigarettes. Within the evaluation, only two products were assessed by the Committees; one which reached a maximum heating temperature of 350 °C and the other was reported to be less than 50 °C. For comparison, when a cigarette is burnt and inhaled, it reaches temperatures of at least 800 °C.
When comparing both devices to conventional cigarettes, the Committees found that heat-not-burn products showed a decrease in the harmful and potentially harmful compounds exposed to users. The Committees also noted that the sidestream emissions from these devices were decreased when compared to traditional smoking
Ultimately, the Committees made the conclusion that while not entirely safe, heat-not-burn products reduced a user’s exposure to certain compounds generally associated with smoking and that there was likely a reduction in overall risks to health for conventional smokers who switch to heat-not-burn products. The Committees did note that while there would likely be a reduction in risk for smokers switching to heat0not-burn products, the most beneficial thing for smokers to do would be to quit smoking entirely.
*https://cot.food.gov.uk/sites/default/files/heat_not_burn_tobacco_summary.pdf*
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