heated tobacco product heated tobacco product a heated tobacco product (htp) is a tobacco product that heats the tobacco at a lower temperature than conventional cigarettes. these products contain nicotine, which is a highly addictive chemical. the heat generates an aerosol or smoke to be inhaled from the tobacco, which contains nicotine and other chemicals. htps may also contain additives not found in tobacco, including flavoring chemicals. htps generally heat tobacco to temperatures under 600 °c (1100 °f), a lower temperature than conventional cigarettes. not to be confused with electronic cigarette. htps use embedded or external heat sources, heated sealed chambers, or product-specific customized cigarettes. whereas e-cigarettes are electronic devices that vaporize a liquid containing nicotine, htps usually use tobacco in leaf or some other solid form, although there are some hybrid products that can use both solid tobacco and e-liquids. there are various types of htps. the two most common designs are those that use an electric battery to heat tobacco leaf (e.g., iqos, glo, pax) and those that use a carbon ember that is lit and then heats the tobacco (e.g., eclipse, revo, teeps). there are similar devices that heat cannabis instead of tobacco. a 2016 world health organization report did not find any evidence to support claims of lowered risk or health benefits compared to conventional cigarettes. a 2018 public health england report includes evidence that indicates htps may be safer than traditional cigarettes, but less safe than e-cigarettes. some htp aerosols studied were found to contain levels of nicotine and carcinogens comparable to conventional cigarettes. although heated tobacco products may be less dangerous than cigarette smoking, the uk committee on toxicity suggests that it would be better for smokers to completely stop. there is insufficient evidence on the effectiveness of htps on quitting smoking, or possible effects of second-hand exposure. the limited evidence on air emissions from the use of htps indicates that toxic exposure from these products is greater than that of e-cigarettes. smokers have reported htp use to be less satisfying than smoking a cigarette. as early as the 1960s, tobacco companies developed alternative tobacco products. htps were introduced into the market in 1988, though they were not a commercial success. the global decline in tobacco consumption may be one reason the industry has invented and marketed new products such as htps. the latest generation of heated tobacco products may be an industry attempt to appeal with governments and health advocates by presenting a potential (but unproven) "harm reduction" product. current smoking bans may or may not apply to heated tobacco products. health effects e-cigarette emissions machine with heated tobacco products. the emissions of four heated tobacco products can be generated in parallel in an emissions experiment. the emissions generated are analyzed using appropriate analytical techniques, which allows a comparison of different applications and products. a 2016 cochrane review found it unclear if the use of heated tobacco products (htps) would "substantially alter the risk of harm" over traditional cigarettes. as of december 2017, it is impossible to quantify the health risk from using these products, as there is very limited information available on health effects. it is unclear as to what the short- and long-term adverse effects are. as of 2019, a limited number of independent studies have been conducted on htps, and further research will likely increase understanding of health effects. the different types of available htps vary in effect, creating a challenge for researchers. it is unknown how users evaluate product safety—one study found that about half of people believed they are safer than traditional cigarettes. a 2016 world health organization report stated that claims of lowered risk or health benefits for htps compared with traditional cigarettes were based on industry-funded research, and compelling independent research was unavailable to support these claims. it also noted evidence that htps may be as dangerous as traditional cigarettes. action on smoking and health in the uk stated in 2016 that due to "the tobacco industry's long record of deceit" regarding the health risks involving smoking, it is important to conduct independent studies into the health effects of tobacco products. with an assorted range of electronic cigarettes devices available in the uk, it is unclear if htps offer any favorable benefit as a plausible harm reduction product. a 2018 public health england report states that htps may be much safer than traditional cigarettes but less safe than e-cigarettes. in a 2017 non-technical summary written by the committee on toxicity, it recommends that smokers completely stop, even though it found htps to be less harmful than smoking. emissions further information: composition of heated tobacco product emissions heated tobacco products expose the user and bystanders to an aerosol. the aerosol contains levels of nicotine, volatile organic compounds, and carcinogens comparable to regular cigarettes; they have also been found to contain more acenaphthene than regular cigarettes. other traditional cigarette emission substances such as tar, nicotine, carbonyl compounds (including acetaldehyde, acrolein, and formaldehyde), and nitrosamines are also found in htps. a 2017 study found a 10% rise in carbon monoxide and formaldehyde air levels when htps were used indoors. another 2017 study discovered htps generated emissions of metal particulates, organic compounds, and aldehydes, and suggests that htps generate less concentrations of airborne contaminants in indoor places in comparison to a traditional cigarette, though their use still reduces indoor air quality. a 2018 public health england report found that "ompared with cigarettes, heated tobacco products are likely to expose users and bystanders to lower levels of particulate matter and harmful and potentially harmful compounds (hphc). the extent of the reduction found varies between studies." it also noted that the evidence indicates that less nicotine was inhaled from htps than cigarette smoke, and exposure to mutagenic and other harmful substances is lower than with traditional cigarettes, though reduced exposure to harmful substances does not correlate with health risk severity. even low exposure can increase the risks for cancers, stroke, and other cardiovascular diseases compared to non-smokers. lower levels of harmful emissions have been shown, but lowering the risk to the smoker who transitions to using them has not been shown, as of 2018. in 2017, the committee on toxicity found that htps do not reduce exposure or potential addiction to nicotine; some of the substances inhaled from using these products are carcinogens. physiological changes in response to heated tobacco emissions, such as multiple organ system inflammation, energy metabolism, and carcinogenesis, have not been well characterised due to limited research in this area, especially in animal models. a 2018 in vitro study suggested a less harmful pathophysiological response in human organotypic oral epithelial cultures when exposed to such emissions. a 2016 animal study showed that heated tobacco emissions did not increase surfactant lipids and proteins, inflammatory eicosanoids and their metabolic enzymes, and several ceramide classes in htp-exposed mice when compared with their counterparts that were exposed to cigarette smoke. it also discovered that even with reduced toxicants in htp emissions, overuse (40 tobacco sticks per day) can still lead to eosinophilic pneumonia in humans. the impact on the overall population is unclear. studies on second-hand htp emissions as of 2018 were diverse and largely affiliated with manufacturers. there is disagreement over the extent to which htps generate air emissions, and the emissions' composition. there is anticipated to be a reduced risk to bystanders where smokers were using heated tobacco products instead of smoking. limited evidence on air emissions suggests that toxic exposure from htps is greater than from e-cigarettes. there is no safe level of exposure to harm carcinogens, making it difficult to assess how much htps reduce health risks. addiction and quitting htps contain the highly addictive chemical nicotine. the nicotine content between htp and traditional cigarette emissions are in similar ranges, which suggests a similar addictiveness and dependence potential. there is insufficient evidence on the efficacy of heated tobacco products on quitting smoking. a 2018 world health organization report states that "onclusions cannot yet be drawn about their ability to assist with quitting smoking (cessation), their potential to attract new youth tobacco users (gateway effect), or the interaction in dual use with other conventional tobacco products and e-cigarettes." in 2017, the ministry of health in new zealand stated that "here is limited information on product use, including whether smokers are likely to switch completely from tobacco smoking or use both types of product, as well as initiation by non-smokers (including young people)." in 2017, the committee on toxicity stated "he committees were concerned over the potential for non-smokers including children and young people, who would not otherwise start to smoke cigarettes, to take up using these products as they are not without risk." the availability of flavours in htp products may appeal to non-smokers, and evidence suggests that individuals who have never used tobacco products, especially children and adolescents, could be susceptible to new products that could lead to the use of traditional cigarettes. in 2017, the committee on toxicity noted that "ommittees were particularly concerned for young people, who do not smoke, starting to use these products, due to the potential for longer exposure over the remainder of their lives compared to adults and to possible differences in sensitivity." the dual use of htps and combustible products is common. trying an htp was more frequent among adults below the age of 30 and regular traditional cigarette users. a 2015 online survey found that 6.6% of 8240 respondents had tried an htp at least once. research demonstrated that there is a high overlap between htp users and female smokers. according to four epidemiological papers, 10–45 per cent of non-smokers use these products, and show the effectiveness of the marketing of the tobacco industry; for example, the htp known as iqos acts more as a gateway to traditional cigarette use (20% of users) than as a means of quitting (11% of users), and is not anticipated to have a lowered risk among dual users who make up the remaining 69%. in 2016 philip morris international (pmi) acknowledged that iqos is probably as addictive as tobacco smoking. iqos is sold with a warning that states the best option is to avoid tobacco use altogether. iqos can record the user's smoking habits. while philip morris international stated it only retrieves the data when the product is not working properly, gregory connolly, a professor at northeastern university who has studied iqos, said that tobacco companies like pmi would have a "mega database" of americans' smoking habits, and possibly "reprogram the current puffing delivery pattern of the iqos to one that may be more reinforcing and with a higher addiction potential". as of july 2017, not many us adults had tried using an htp; approximately one in twenty us adults (including one in ten traditional cigarette users) have heard of htps. in italy, htp use was 1.4% among the people and 3.1% among regular tobacco users. a 2018 survey in italy found that 45 per cent of people who experimented with the iqos and 51 per cent who were interested in the product had never smoked before. therefore, such a product may represent, at least in italy, a gateway for nicotine addiction among never-smokers rather than a harm reduction substitution for current smokers. in germany, htp use is not common and is generally more frequent among richer and educated smokers. since its sale in japan in 2014, htp use has been high; a 2017 survey in japan found that of those who used the iqos within the last month, 20 per cent had never smoked before. the products did not satisfy 86 per cent of users, and they did not quit using traditional cigarettes; they used both. htp use among youth is unknown, but monitoring is underway as of march 2019. nicotine yield the limited data on htp users show that they take short puffs and that the time between puffs is very short. experimental tests show a higher volume of puffs at shorter intervals than with traditional cigarettes. a 2018 clinical trial found that tests of smokers switching to iqos showed a tendency to take more puffs at shorter intervals. users experience blood nicotine levels that peak after six to seven minutes for both htps and traditional cigarettes. the iqos produces slightly less blood nicotine overall than a traditional cigarette, but more