Combustion is the process of burning something, and it requires three elements: a fuel source, like tobacco; oxygen, found in air; and enough heat to kickstart the self-sustaining, heat-generating reaction. During combustion, in ideal conditions, hydrocarbons and oxygen react to form carbon dioxide and water. In more realistic settings, for example in combusted cigarettes, there is not enough oxygen available for complete combustion to occur. Incomplete combustion leads to the production of carbon monoxide and numerous other molecules, of which many have been recognized by health authorities to be harmful or potentially harmful. Some of the toxicants emitted during combustion form liquid and solid particles that, together with the rest of the emissions, result in smoke that can be harmful to health if inhaled. Smoking a cigarette involves combustion and the generation of smoke. Millions of smokers every year decide that they don’t need cigarettes in their lives and quit completely. They make the single best possible choice a smoker can make for their health: they quit tobacco and nicotine completely. Still, there are many men and women who decide that while they don’t want to smoke, they do want to continue using nicotine and tobacco products. They are looking for similar taste, rituals, and nicotine uptake as those of cigarettes, but without the smoke. Thanks to technological advancements in smoke-free products, those experiences can be delivered without combustion. Cigarette smoke also contains certain metals because tobacco plants require essential minerals for growth, and because the metals are also found in soil Nicotine in cigarette smoke is transferred from the tobacco at temperatures up to its boiling point around 247°C. That’s far below the temperature at which tobacco begins to burn, around 400°C. That means it’s possible to heat tobacco enough to release nicotine without burning it and producing smoke. Heated Tobacco Products (HTPs) do exactly this. Alternatively, e-vapor products heat an e-liquid to release nicotine and flavors, while also avoiding combustion and smoke. Tobacco – like many materials – loses mass into the air as it is heated through a range of temperatures. First, the drying process: it loses moisture between 30-150°C. From around 100-300°C, various chemicals besides water are evaporated from the tobacco as a result of the heat alone, and some of the tobacco components are broken down. Nicotine is also released from the tobacco at these temperatures. Above this range, the presence of oxygen begins to become important as the tobacco draws closer to the ignition temperature. Below about 400°C, there’s not too much of a difference between the processes that occur in tobacco that’s heated in air with oxygen versus tobacco that’s heated without oxygen. But above 400°C, there’s a big difference: in oxygen, it burns. Thousands of components have been identified in tobacco plants, and it’s estimated that thousands more are waiting to be discovered. Like any plant, tobacco takes simple elements and converts them into macromolecules for growth and self-maintenance. That process is further compounded by the burning of its cured and dried leaves to create the complex mixture of more than 6000 chemicals that constitute tobacco smoke. Cigarette smoke also contains certain metals because tobacco plants require essential minerals for growth, and because the metals are also found in soil. Almost every metal found in tobacco can transfer in small amounts into cigarette smoke when the tobacco is combusted. Among these, arsenic, beryllium, chromium, nickel, and cadmium are listed as human carcinogens by the International Agency for Research on Cancer (IARC) as of 1985. With all the toxins and health risks associated with cigarette smoking, smoke-free or Heat not Burn (HnB) technology provides better alternatives for smokers who don’t want to quit completely, inadvertently breaking a bad habit. Recently, the US Food and Drug Administration (FDA) also approved the marketing of tobacco reduced risk products to provide smokers with scientific, facts based information to enable them in making better choices to reduce health risks from smoking. Through the modified risk tobacco product application process, the FDA aims to ensure that information directed at consumers about reduced risk or reduced exposure from using a tobacco product is supported by scientific evidence. If these e-cigarettes are regulated in Pakistan it can help reduce the number of annual deaths due to the smoking-related disease by completely shifting the current smokers to e-cigarettes and also save millions of rupees costing to the national exchequer in terms of the tax evading the local illegal cigarette manufacturers. The writer is a freelancer