Human Biomarker Exposure From Cigarettes Versus Novel Heat-Not-Burn Devices: A Systematic Review and Meta-Analysis

Abstract

Introduction Novel tobacco products require independent research to assess their safety. This study assessed the current literature for trials comparing levels of biomarkers of exposure (BoE) between conventional cigarettes (CC) and heat-not-burn (HNB) devices. Methods Ten databases were searched using terms including: “heat not burn,” “iqos,” “teeps,” “mrtp,” “tobacco heating,” and “glo” between January 1, 2010 and August 13, 2019. Randomized controlled trials (RCTs) assessing comparative BoE levels in humans using either CC or novel HNB devices were eligible. BoE were tabulated, and differences between the intervention and control groups were analyzed and combined using a random-effects meta-analysis. Results Ten nonblinded, RCTs were eligible, involving a total of 1766 participants. Studies regularly reported on 12 BoE (including nicotine). HNB devices assessed included the “IQOS” and “glo” devices and “precursor” (being developed) HNB devices. In comparison to CC, all 12 BoEs assessed were significantly lower for participants assigned to an HNB device. In comparison to smoking abstinence, HNB devices were statistically equivalent for eight BoEs and significantly elevated for four BoEs. Conclusions This review found that the potential for harm to humans is reduced when using HNB devices compared to CC as indicated by significant reductions in BoE levels. Whilst these results support tobacco manufacturer claims of improved safety, the small number of studies included, limited range of BoE assessed, and involvement of the tobacco industry necessitate further independent research to confirm the HNB devices as being a safer alternative to CC. Implications This study supports claims made by tobacco manufacturers on the improved safety of HNB tobacco devices in comparison to CC. These novel devices lead to reduced exposure to key biomarkers, which are linked to the health consequences attributed to tobacco use. This has strong implications for international public health as well as further research and policy development relating to the safety aspects and legalities of novel tobacco products.

The product science of electrically heated tobacco products: a narrative review of the scientific literature

“…These findings are in agreement with the conclusions of two published systematic reviews on the levels of biomarkers of exposure associated with use of heated tobacco products (Drovandi et al, 2020;Akiyama and Sherwood, 2021). The first systematic review identified ten randomised controlled trials involving 1,766 participants published between January 2010 and August 2019 which quantified twelve biomarkers of exposure after controlled use of both heated tobacco products and conventional cigarettes (Drovandi et al, 2020). Seven of these ten studies are detailed in Table 3 whilst the other three articles related to either use of a hybrid product (n=2) or a carbon-heated tobacco product (n=1) both of which are outside the remit of this review.…”

“…The authors of this systematic review concluded that "in comparison to conventional cigarettes, all twelve biomarkers of exposure assessed were significantly lower for participants assigned to a heat-notburn device. In comparison to smoking abstinence, heat-not-burn devices were statistically equivalent for eight biomarkers of exposure and significantly elevated for four biomarkers of exposure" (Drovandi et al, 2020). The second systematic review identified twenty-five randomised controlled trials published up to April 2020 which quantified twelve biomarkers of exposure after controlled use of both heated tobacco products and conventional cigarettes (Akiyama and Sherwood, 2021).…”

Cross-sectional study on the awareness, susceptibility and use of heated tobacco products among adolescents in Guatemala City, Guatemala

“…4 5 However, current evidence on the harmful effects of HTPs compared with conventional cigarettes is yet to be determined as most of the available evidence is in vitro and comes from tobacco industry-funded research. [6][7][8][9] In July 2020, the Food and Drug Administration (FDA) authorised Philip Morris to make claims in its HTP (IQOS) marketing about reduced exposure to harmful constituents compared with cigarettes; however, the FDA prohibited marketing claims about reduced risks from IQOS use, citing the lack of evidence for this claim. 10 11 Nevertheless, consumers equate reduced exposure with reduced risk 12 : HTPs appeal to adult smokers and use of HTPs has been rapidly increasing in some high-income countries (HIC) where they have been introduced, suggesting a potential public health benefit, similar to that of e-cigarettes.…”

Novel Solvent-Free Extraction Method for Analyzing Tobacco Heating Product Aerosols: An Analytical and In Vitro Toxicological Five-Way Product Comparison

“…Methods for Quantification of Aerosol Components. The target component levels of TPM captured in the CFP and the centrifuged liquids were determined according to the following procedure: (1) The mass of the total amount of THP aerosols collected on the CFP and the mass change of the CFP before and after centrifugation were measured gravimetrically. (2) For nicotine, glycerol, propylene glycol, and water determination, CFPs were extracted using isopropanol, and the extract was analyzed via gas chromatography with a flame ionization detector (gas chromatography-flame-ionization detection (GC-FID) and gas chromatography with a thermal conductivity detector (GC-TCD) for water), according to the CORESTA recommended method number 84.…”

“…Over the past few years, the use of tobacco heating products (THPs) has grown rapidly in many countries around the world. These products have become an attractive alternative to conventional cigarettes because they are considered less risky and are promoted as smoking cessation aids, despite little evidence that they can effectively help smokers to quit. − However, there are ongoing concerns about the safety and long-term toxicity of using these products. For example, hazardous chemicals such as toxic carbonyl compounds (acetaldehyde, formaldehyde, and acrolein) have been detected in THP aerosol emissions, while other toxic substances such as heavy metals from heating coils have also been measured.…”