The Burning Issue

By Celia Spegel

Burned matches

As September is ‘Science Month’, let’s start by taking a look at the IQOS science behind heated tobacco technology.

What happens when you light a cigarette?

When you light a cigarette and draw on it, the tobacco and the oxygen in the air combine to start a high-temperature reaction. This is called combustion but is more commonly known as burning. The burning produces cigarette smoke which contains the tobacco flavours and nicotine (nicotine is found naturally in tobacco leaves).

Why was heated tobacco developed?

As Philip Morris International, we believed there had to be a better alternative to smoking cigarettes that would still deliver flavour and nicotine. Since 2008, over 400 leading IQOS scientists and scientific experts in chemistry, biology, informatics and medicine collaborated on developing and assessing PMI’s smoke-free products.

We spent ten years in R&D to develop an innovative product that doesn’t rely on the principle of burning and which, as shown by our science, is a better alternative than smoking: IQOS.

How does heated tobacco work?

The material in cigarettes needs a very high temperature of over 600°C to burn and produce smoke.

IQOS scientists developed a unique electronic system with HeatControl™ Technology. This heats tobacco within a precisely controlled temperature range that doesn’t go above 350 °C - due to the heating blade inside the IQOS holder that also acts as a temperature sensor.

Apart from heating tobacco instead of burning it, is IQOS like a cigarette?

IQOS is different to a cigarette in several ways. When you smoke a cigarette, the tobacco leaves and paper burn away to result in ash. However, IQOS doesn’t produce fire, ash or even cigarette-like smoke. Instead, IQOS has less smell compared to cigarettes.

IQOS heat not burn technology also means no tar is produced.

The 6,000 chemicals in cigarette smoke include arsenic, benzene, carbon monoxide, heavy metals, hydrogen cyanide and tobacco-specific nitrosamines. Importantly, IQOS emits on 95% less harmful chemicals compared to cigarettes - a significant difference*. Important information: It does not necessarily equal a 95% reduced in risk. IQOS is not risk-free. *Average reduction levels of a broad range of harmful chemicals (excluding nicotine) compared to the smoke of a reference cigarette (3RF4)

Has IQOS been scientifically proven to be better than cigarettes?

When it comes to research and development, we adhere to the same rigorous scientific methods, assessments and principals as global pharmaceutical companies.

We present IQOS PMI science findings at scientific conferences and publish them in peer-reviewed journals and on our PMIScience website. All our clinical studies are registered on

We also encourage independent research and studies, once again publishing the papers on our PMIScience website for total transparency.

Our studies show that switching completely to IQOS is likely to present less risk to your health than continuing to smoke*. However, IQOS is not risk-free and is addictive so the best choice is to quit tobacco and nicotine altogether. *Source: Based on the totality of evidence available for IQOS in comparison with continuing to smoke.

Has PMI addressed the issue of burning in any other ways?

Yes, IQOS MESH, our new vaping technology, delivers flavours and nicotine without using tobacco.

This vaping technology uses liquid nicotine extracted from tobacco leaves and is designed with smart digital controls. These detect low e-liquid levels to avoid overheating and a burnt taste.

If you have any burning issues about IQOS and the science behind it, please get in touch by phone or else via FacebookTwitter or LiveChat on our IQOS website.

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This website is intended only for users of nicotine or tobacco products who are over 18.

This website is restricted to adults in the United Kingdom who would otherwise continue to smoke or use nicotine products. Our nicotine and tobacco products are not an alternative to quitting and are not designed as cessation aids. They are not risk-free. They contain nicotine, which is addictive. Only for use by adults. Please visit the Important Information page for further risk information.