Heated Tobacco Products

      Heated tobacco products (HTPs), also known as heat-not-burn (HnB) products, do exactly what their name suggests: they are designed to heat tobacco instead of burning it. That is the fundamental difference between HTPs and cigarettes. Because tobacco is heated and not burned, our HTPs do not produce smoke, but instead, create aerosols with significantly reduced levels of harmful chemicals compared with cigarette smoke. In this page, we review what heated tobacco products are as a category and give further insight into our own products and the science supporting them. HTPs are not risk free, and provide nicotine, which is addictive.

      What are heated tobacco products?

      HTPs are designed to heat tobacco instead of burning it, generating as a result an aerosol with significantly lower levels of harmful chemicals compared with cigarette smoke. 

      Some HTPs are electronic, but not all, and the exact temperature the tobacco is heated to varies from product to product. The important thing is that HTPs should avoid the high temperatures where tobacco is burnt, while providing nicotine. In this category, you have products that vary in heating sources, tobacco processing, flavors, and designs, with new technologies still in development. So, although HTPs are a class of products, whether they actually reduce the level of harmful chemicals compared with cigarettes needs to be assessed on a product-by-product basis. 


      What are PMI’s heated tobacco products? 

      At Philip Morris International (PMI), we employ a diverse set of heating technologies to support our range of HTPs. The Tobacco Heating System (THS), our leading HTP commercialized under the IQOS brand, offers devices which use internal resistive heating as well as induction heating technology, while our Oven Heating System (OHS), commercialized as BONDS by IQOS, uses instead external resistive heating. Our portfolio also includes devices developed by KT&G, the leading South Korean tobacco and nicotine company, which use different heating technologies.  


      How do our heated tobacco products work?

      An HTP comes in two main parts: the heating source in a device, and the tobacco in a specially designed tobacco stick. The heating source will heat the tobacco stick to release nicotine and aromas with much lower levels of harmful chemicals compared with cigarette smoke.  

      HTPs use a diverse array of technologies to heat the tobacco within a precisely controlled temperature range to avoid burning it. At PMI, we apply two distinct technological approaches: resistive and induction. Both technologies heat a specially designed tobacco stick to release an aerosol. 

      Resistive heating

      This form of heating technology can be applied either internally, by inserting a heating blade or a pin in the tobacco stick, or externally, by wrapping the tobacco stick with a heating element.

      Induction heating

      This form of heating technology employs a magnetic field to heat up the tobacco. When a specially designed tobacco stick is inserted inside the heating device, an electric current flows through a coil present in the heating device, and a magnetic field is created. This field heats up a metallic element, and with it, the tobacco within the stick, producing an aerosol.

      Tobacco Heating System

      Internal resistive heating using a blade

      Developed over 15 years ago, the THS product category started by using a heating blade which is inserted directly into the tobacco plug. Once turned on, the blade heats the tobacco radially outwards from the center of the tobacco plug while also monitoring its temperature to ensure consistent taste and avoid burning. The resistive heating devices which use blade technology comprise THS 2.0, THS 2.1, and THS 2.2, also known commercially as IQOS Originals.

      Pin-based Heating System

      Internal resistive heating using a pin

      We also have in our product portfolio the Pin-based Heating System (PHS)*, developed by KT&G. As its name indicates, PHS uses a pin instead of a blade to heat a tobacco stick and uses internal resistive heating technology, similarly to THS.


      * Also known commercially as lil Solid Ez.

      Oven Heating System

      External resistive heating or peripheral heating

      This form of heating technology, also known as Oven Heating System (OHS), employs a flexible resistive heater which surrounds the tobacco stick and heats its external surface. The heater is made of flexible polyimide stainless-steel tracks wrapped around a stainless-steel tube, with an insulated thermal casing around it. The device developed to use this heating technology is THS 6.0, also known commercially as BONDS by IQOS.

      Tobacco Heating System

      Induction heating using a metallic strip

      Embedded inside the tobacco stick is a metallic strip, known as a susceptor, removing the need for a direct contact between the electronics and the heating element. The THS device that uses induction technology is THS 3.0, also known commercially as IQOS Iluma.


      In addition to tobacco sticks specially designed to be used with induction technology, we have developed tobacco-free nicotine-containing sticks which also generate a nicotine-containing aerosol when heated in THS 3.0. These tobacco-free sticks are known commercially as LEVIA.

      Aerosol heating system

      Other heating technologies

      The Aerosol Heating System (AHS)*, also developed by KT&G, combines elements of heated tobacco products and e-vapor products into a single hybrid system.


      * Also known commercially as lil Hybrid.

      How are heated tobacco products different from cigarettes?

      HTPs are not the same as cigarettes which burn the tobacco. Through the combustion of tobacco, cigarettes produce smoke, a complex, chemical mixture, with billions of carbon-based solid particles and more than 6,000 constituents identified. Within this complex mixture, about 100 chemicals have been associated with smoking-related disease by public health authorities. These constituents are also known as harmful and potentially harmful constituents (HPHCs). HTPs heat the tobacco instead of burning it, releasing aerosols which, while not risk free, may contain lower levels of harmful chemicals than found in cigarette smoke. 


      How are heated tobacco products different from e-cigarettes?

      Similarly to HTPs, e-cigarettes—also known as e-vapor products or vapes, vape pens, or e-cigs—produce an aerosol with potentially significantly reduced levels of harmful constituents compared with cigarette smoke. As is the case for HTPs, whether an actual product reduced the level of harmful chemicals has to be substantiated on a product-by-product basis. However, e-cigarettes do not heat tobacco, but instead, heat a liquid that generally, but not always, contains nicotine as well as flavorings. 

      What scientific data is available behind our heated tobacco products?

      Each HTP should be assessed on a product-by-product basis. In the case of our HTPs, we have demonstrated so far that by not burning tobacco, it does not create smoke, but instead, an aerosol which, while not risk free, contains 90-95% lower levels of harmful chemicals than found in cigarette smoke. Note that this does not equate to a 95% reduction of risk. However, we have accumulated nonclinical and clinical data to support the potential of our HTPs to reduce the risk of developing smoking-related diseases compared with continued smoking.  

      For more details on the scientific substantiation behind our HTPs, you can find our scientific publications—most of which are open access—through the publications library, or summaries of some of our research and independent publications via our literature reviews page.


      Is there secondhand smoke from heated tobacco products?

      Because of the way HTPs are designed, they should not create smoke, and thus should not generate secondhand smoke. As such, our studies have shown that the use of THS, our leading HTP, does not adversely affect overall indoor air quality. Out of 24 measured compounds, only the increase of the indoor concentrations of nicotine, acetaldehyde, and glycerin above the background was attributable to the use of THS 2.2, and in concentrations well below the exposure limits defined in air quality guidelines.


      The scientific evidence

      For over 30 years, we have developed and assessed a range of HTPs so that every adult smoker who would otherwise continue to smoke cigarettes can find a suitable, scientifically substantiated less harmful alternative that helps them to fully switch away from cigarettes, the most harmful way of nicotine consumption. To achieve this, we employ rigorous and robust scientific techniques inspired by the biotech and pharmaceutical industries, publish our results in scientific journals, and make them as well available via our publications library.