THP – Tobacco Heating Products
Tobacco heating products (THPs) are devices that heat tobacco to generate a nicotine-containing aerosol with a tobacco taste which the user inhales. Because the tobacco is only heated and not burned, the resulting aerosol can potentially contain substantially lower levels of the toxicants found in the smoke produced when tobacco is burned.
The scientific community widely agrees that the majority of smoking-related diseases are caused not by nicotine but by toxicants present in the tobacco or its smoke, formed during the combustion and pyrolysis of tobacco.
Tobacco heating products use blended or processed tobacco, just like conventional cigarettes. They work by heating tobacco sufficiently to vaporise the nicotine and some other volatile compounds in the tobacco into an inhalable aerosol stream, but not high enough to burn the tobacco. As a result, the aerosol produced by tobacco heating products contains fewer toxicants, the majority of which are at significantly lower levels than in cigarette smoke.
Using lab based machines, we compared the vapour of the tobacco heating product glo™ against a scientific reference cigarette, for the priority toxicants proposed by: World Health Organisation (9 chemicals), Food & Drug Administration (list of 18 chemicals and 93 Harmful and Potentially Harmful constituents) and Health Canada (44 chemicals). Chemical studies of glo™ vapour show around 96 – 97 % reduction of toxicants which health organisations recommend to reduce.
We have developed a special exposure chamber system that allows us to deliver whole smoke or aerosol to lung cells at the air–liquid interface, a much more physiologically relevant testing scenario than traditional tests. Both simple lung cell cultures and more complex 3D tissues can be used in the chamber; this system is allowing us to conduct all sorts of lab-based biological tests that allow accurate comparison between the impact of cigarette smoke and tobacco heating product’s aerosols.
Results from these more sophisticated in vitro tests suggest that our tobacco heating products have much reduced or no toxic effect compared to cigarette smoke. The results clearly show that exposure to cigarette smoke has a strongly adverse effect on cells, triggering thousands of changes in expression of genes involved in oxidative stress, inflammation and fibrosis, which are cellular processes that underlie smoking-related diseases such as lung cancer and COPD (Chronic Obstructive Pulmonary Disease). In contrast, exposure to vapour from Vype ePen or aerosol from glo™ induces very few changes in gene expression — it’s a striking difference.
Pic. 2 Exposure to cigarette smoke (left) triggers thousands of changes in expression of genes in processes that underlie development of smoking-related disease. In contrast, aerosol from glo™ (right) induces far fewer disease-relevant changes in gene expression.