Tobacco products have been defined by the World Health Organization (in its Framework Convention on Tobacco Control) as those entirely or partly made of leaf tobacco as the raw materials, which are intended for smoking, sucking, chewing or snuffing.1 In Australia, cigarettes are the most common tobacco product. Most of the research on the health effects of tobacco products and the tobacco industry centres on ready-made, manufactured cigarettes. These are most commonly termed ‘factory-made cigarettes’ in the research literature, however many Australian smokers use the term ‘tailor-made’ cigarettes. Many Australian smokers buy manufactured loose tobacco products (‘roll-your-own’ tobacco) suitable for hand-rolling cigarettes. These are often referred to by smokers as ‘rollies’. Roll-your-own tobacco is also used for rolling cigarettes using a small portable machine (referred to by several of the manufacturers as ‘make-your-own’ tobacco). Cigars and pipe tobacco products are widely available but less popular than cigarettes. On a worldwide scale, other forms of tobacco smoking are commonly practised but have received substantially less attention from researchers. Many different cultures throughout the world continue to practise tobacco smoking using traditional pipes. Kreteks are a popular tobacco product with clove flavour in Indonesia. Bidis are hand-rolled tobacco products that are popular in many Asian countries and exported widely. Waterpipes are commonly used to smoke loose tobacco in the Middle East and some African and Asian countries.
This section discusses the tobacco used in cigars, roll-your-owns, illicit tobacco (chop-chop), pipes and waterpipes, kreteks and bidis. Heated tobacco products are discussed in Section 18B and smokeless tobacco are discussed below and further in Section 18A. The different varieties of tobacco plants and their growth, curing and other agricultural practices are described in Section 12.1.
A cigar is a roll of tobacco that is wrapped in a tobacco leaf, or another substance containing tobacco. Most types of cigars do not have filters. Cigars differ from cigarettes, mainly in that cigarettes are wrapped in paper and almost always contain a filter. Most cigar smokers only allow the smoke into their mouth and throat. However, people who smoke both cigars and cigarettes often inhale the cigar smoke into their lungs.2 See Section 3.27.3 for more information about the health effects of smoking cigars.
Cigars are usually made from air-cured Broadleaf and seed-leaf tobacco varieties, such as Havana seed, Cuban, and Sumatra tobacco.3 Cigar tobacco is commonly grown in Central America and the Caribbean Islands, and most famously in Cuba.
There are three main types of cigars: large cigars, cigarillos and little cigars. Large cigars (including premium cigars) come in various sizes and are rolled to a tip at one end.1 They usually contain over 5 g of tobacco. Some have as much as 20 g of tobacco, equivalent to an entire pack of cigarettes. Large cigars can take between one and two hours to smoke.2 Cigarillos are small, narrow cigars with no filter. They are usually larger than cigarettes and contain about three grams of tobacco (compared to between 0.5 to 0.8 g for factory-made cigarettes).2 Little cigars are the same size and shape as cigarettes and are often packaged like cigarettes. Little cigars usually have a cellulose acetate filter,4 implying that they are to be smoked like cigarettes, with the smoke inhaled. They may be wrapped in a paper that contains tobacco.
Most cigars have three components: 1) the filler, being a roll of tobacco, 2) the binder, which is a tobacco leaf that holds the filler together, and 3) a wrapper leaf, described as a high-quality tobacco leaf. Cigars may incorporate different types of tobacco leaves (from different parts of the plant) for the filler, binder leaf and wrapper, and blends of different tobacco plants in the filler.
Cigar tobacco leaves are harvested and usually air-cured in barns at consistent humidity, then aged until they meet quality specifications.5 Ageing allows chemical reactions to reduce the levels of sugars, nicotine and other alkaloids, reducing the harshness of the smoke. This can take between six months and two years.5 Most cigars are made by machine, but some premium cigars are hand-rolled. After rolling, by hand or machine, cigars may be aged once more in wooden containers.
The filler is a bundle of full or cut tobacco leaves that are rolled to produce long air pockets, through which the smoke is drawn after lighting. Filler that is rolled too loose will allow too much oxygen to pass through and burn too fast. Filler that is too tight will make the drawing through of air more difficult for the smoker. Filler tobacco is often blended using different types of tobacco plants to create a complex and characteristic flavour and aroma. Having the thickest tobacco in the centre allows for an even burning process.5
The binder is a strong pliable tobacco leaf that holds the filler together. During manufacture, the filler is first rolled in the binder and then covered by the wrapper leaf. Binder leaves contribute less to the taste and do not need to be as visually appealing as the wrapper.5
Wrapper leaves may be grown under cover instead of the full sun. These leaves are cured and aged under more carefully controlled conditions to produce a thinly-veined, pliable leaf of consistent colour.5 Little cigars may be wrapped in reconstituted tobacco or cigarette paper that contains tobacco or tobacco extract.
Cigars may contain additives and flavours, as described in Section 12.6. The chemicals found in cigar emissions are described inSections 220.127.116.11 and 18.104.22.168.
12.2.2 Manufactured loose tobacco (‘roll-your-own’ tobacco) products
Roll-your-own tobacco products are common in Australia. They consist of dried, fine-cut tobacco leaves packaged in pouches or tins.Roll-your-owns, or ‘rollies’, are hand-rolled or machine rolled in paper by the user and may be smoked with or without a filter. Despite user perceptions, roll-your-own cigarettes contain similar amounts of additives, similar levels of toxic chemicals in their emissions and cause similar harms to health as ready-made cigarettes (see Section 3.27.1).
Roll-your-own cigarettes can be made using a manual cigarette rolling machine.6 The rolling machine uses a tube to make standard sizes, with the tube size affecting the amount of tar delivered, according to measurements using a smoking machine.7
While the construction of factory-made cigarettes is highly standardised, roll-your-own cigarettes vary considerably between users. People who smoke roll-your-own cigarettes are reported to take more puffs, inhale more smoke per cigarette and inhale for a longer time during smoking.8, 9
The tobacco varieties used in roll-your-own tobacco products may be flue-cured Virginia, light air-cured Burley or sun-cured Oriental tobacco.10 In Australia, specific tobacco brands are sold for roll-your-own construction. However, pipe tobacco is sometimes used to make roll-your-own cigarettes in other countries.11, 12 Pipe tobacco is discussed separately in Section 12.2.4. In the past, most roll-your-own tobacco sold in Australia was the flue-cured Virginia variety.13 It is difficult to determine what varieties or blends of tobacco are currently sold in Australia as roll-your-own tobacco. The brands sold in Australia are made in New Zealand, Indonesia, the Netherlands and Germany. See Section 12.1.3 for more information on tobacco varieties.
12.2.3 Illicit tobacco (‘chop-chop’)
Illicit tobacco (chop-chop) consists of roughly processed tobacco leaves sold without payment of excise duty. It’s sold either pre-rolled into cigarettes or loose in large bags to be hand- or machine-rolled by the smoker.14 Illicit tobacco is unregulated and inexpensive.15 See Section 3.27.2 for information about the health effects of illicit tobacco and Section 13.7 for details on tax avoidance and evasion.
Illicit tobacco grown in Australia bypasses the routine curing and manufacturing processes used for factory-made products.14 It has been found with contaminants that ‘bulk up’ the weight. Twigs and pulp from raw cotton, hay, cabbage leaves and grass clippings and other vegetable matter have been found in illicit tobacco.14 Bacterial and fungal contamination in illegal tobacco has also been documented. The most concerning contamination comes from aspergillus fungus, which produces the carcinogenic (cancer-causing) aflatoxin.14 Illicit tobacco is also reported to be fumigated with bleach.15
12.2.4 Pipe tobacco
Smoking tobacco in pipes has a long tradition in history but is now uncommon among Australian smokers.
Most pipes consist of a bowl, in which tobacco is packed by the user, and a stem, through which the smoke is drawn. Pipe stems commonly contain a detachable segment to allow for cleaning.16 Disposable filters may be fitted into tobacco pipes. Pipe smoke may not be inhaled into the lungs by the smoker, but rather tasted in the mouth, similar to cigar smoke.17
Pipe tobacco in Australia is commonly sold in tins and differs from that used in roll-your-own cigarettes. It is usually roughly cut (in larger pieces than fine-cut), as cutting too fine does not allow room for air to be effectively drawn through once packed into a pipe.18,19 Pipe tobacco is also more moist than roll-your-own tobacco, allowing for a slower burn. Aromatic pipe tobacco has flavours added to the leaves in a casing, such as whiskey, maple, caramel, vanilla and chocolate.19
Light air-cured Burley tobacco or sun-cured Oriental tobacco may be used in pipes. Pipe tobacco can be a blend of up to 25 different types of tobaccos or made solely of Burley tobacco.4 Pipe tobacco may contain midribs (smaller stem that extends from the main stalk) and additives such as casings.4 Pipe tobacco in many countries is flavoured by additives, which reduce or mask the harshness of the product.20
12.2.5 Waterpipe tobacco
Heating tobacco using waterpipes is common in the Middle East, Africa and many countries in Asia. Alternative names for waterpipes include narghile, arghile, shisha, goza, hubble bubble and hookah.21 In Australia, waterpipe use is popular within specific cultural groups and some younger people.22,23 Waterpipes are believed by some users to be less addictive and harmful than cigarettes.24 However, there is increasing evidence that they are both harmful and addictive.25 See Section 3.27.5 for information on the health effects of using tobacco in a waterpipe.
Waterpipes heat the tobacco with burning coals to produce emissions that are passed through water before inhalation.4 A typical waterpipe heats the tobacco in a bowl, using suction from a hose to draw the smoke down a tube into the water. The tobacco is often covered with foil and heated indirectly with coals, rather than being set alight. For more information about the emission formed from waterpipes, see Sections 22.214.171.124 and 126.96.36.199.
A variety of tobacco types are used in waterpipes.4 Unflavoured tobacco, called ajami, is considered more traditional and has a longer history. Pre-shredded and dried ajami is mixed with a small amount of water to make a mouldable matrix, which is shaped into a small mound in a shallow bowl for smoking.26
Since the 1990s, tobacco called maassel (or mo’assel) has become a popular form used in waterpipes.26 Maassel is fermented in molasses and flavoured with fruit essences or other flavours. Unsurprisingly, it is usually high in additives. Maassel produces smoother tasting emissions with a more attractive aroma than the raw ajami tobacco.26 It is branded as many different flavours including apple, banana, berry, cherry, chocolate, coconut, coffee, cola, grape, kiwi, lemon, liquorice, mango, mint, orange, peach, pineapple, rose, strawberry, tutti fruity, vanilla, and watermelon.27 Maassel is a very moist and sticky type of tobacco. Waterpipe users may spread it out in the bowl with a toothpick to make room for air to flow through. Typically, 10 to 20 g of maassel would be used in a 3 cm deep bowl. This may be shared by a group or used by one person, in a session lasting between 15 minutes and two hours or longer.26
Kreteks are cigarettes that originated in Indonesia. They contain cloves, clove oil and other spices. The emissions from kreteks are described in Section 188.8.131.52, the health effects of smoking kreteks in Section 3.27.6 and the additives in kreteks in Section 12.6.1.
Traditional kreteks are hand-rolled in a corn husk wrapper. Contemporary kreteks are mass-produced, paper-wrapped and rolled by machine, however hand-rolled and corn-husk wrapped kreteks are also available.28 Kreteks are often blended, with up to 30 different types of tobacco reported as being used in these blends.29 Tobacco used in kreteks is usually that grown in Indonesia (in Java, Sumatra, Bali, and Lombok). It may be sun-cured and aged for years before use.29 Kreteks are available with and without filters.28
Bidis are small, thin, hand-rolled cigarettes that are popular in India, Bangladesh, Nepal, Sri Lanka, Pakistan and the Maldives. They consist of sun-cured tobacco flakes rolled in a piece of dried tendu or temburni leaf (from plants native to Asia).30 Alternative names for bidis are beedis, beedies or biris. Due to their low cost, bidis are popular with low to middle wage earners and exported to many different countries including Australia.31
Bidis are mass-produced, but the process is usually labour-intensive. After sun-curing, stalks are torn out of the tobacco leaves by hand. The tobacco is then pounded into flakes, by hand or by machine. At this stage, the tobacco is stored for 6 to 12 months to age. Different types of tobacco may be blended, and crushed stems and ribs added to improve combustibility. The tobacco is hand-rolled in a prepared tendu or temburni leaf and secured with a thread. The final product varies in length from four to eight cm.31 Bidis are often flavoured, therefore containing additives, discussed in Section 12.6.1.
The leaf wrapper contributes to approximately 60% of the bidi weight, unlike cigarettes which are about 90% tobacco filler by weight. Bidis have approximately 0.2 g of tobacco;31 less than commercial cigarettes, which in Australia range from about 0.4 to 0.8 g (see Table 12.1 in Section 184.108.40.206). The leaf wrapper is relatively non-porous and does not burn as readily as the paper or tobacco leaf wrappers of cigarettes or cigars. This requires more frequent and deeper puffs by the user to keep the bidi alight.31
12.2.8 Heated tobacco products
Heated tobacco (heat-not-burn) products use external heating to release emissions from tobacco rather than burning. Products such as Philip Morris’s iQOS, British American Tobacco’s glo and Japan Tobacco’s Ploom heat tobacco in pre-made cigarette-like sticks, containing filters and plugs of tobacco. There is little publicly available information on the type of tobacco used in these products. The varieties of tobacco used in iQOS, for example, are redacted in the publicly available application to the FDA.32 For a detailed discussion of these products, see InDepth 18B.
12.2.9 Smokeless tobacco products
Smokeless tobacco refers to numerous different tobacco products that are used orally or nasally. This section contains a brief description of the different types of smokeless tobacco. For a detailed discussion of the use of smokeless tobacco, see InDepth 18A.
Historically, the known use of smokeless tobacco products dates back to 1400 and occurred in diverse populations over multiple continents.33 A wide range of smokeless tobacco products therefore exist, with many used only by specific populations of people. Smokeless tobacco use is rare in Australia and its sale has been prohibited since 1991.34
Smokeless tobacco is not heated during use, so does not usually contain many of the toxic chemicals produced during pyrolysis and combustion found in products that are heated. However, some types of smokeless tobacco, such as Indian dry snuff and Mishri, are roasted or partially burnt during their manufacture, and therefore likely to contain toxic chemicals produced during pyrolysis.33
Many different types of smokeless tobacco are described in Volume 89 of the IARC Monographs on the Evaluation of Carcinogenic Risks to Humans,33 including the following:
Creamy snuff is a finely ground tobacco mixed with aromatic compounds such as clove oil or menthol. It is used most often by women in South East Asia as a tooth cleaner.33
Dry snuff is used orally or nasally. In Europe and the US, dry snuff is made from Kentucky or Tennessee tobacco that is fire-cured, fermented and processed into a dry, powdered form with a low moisture content. Dry snuff in India is roasted and ground into a powder. The roasting process is likely to involve pyrolysis and therefore the production of toxic chemicals.33
Gudhaku and Gul are pastes made of powdered tobacco, molasses and other ingredients. They are used orally, often by women in India and South Asia.33
Gutka is a tobacco product that is popular in India, Pakistan and other Asian countries. Gutka is a mix of tobacco and pan masala— a dried powdered mix of areca nut, catechu, lime and spices.35 The tobacco in Gutka is sun-dried, roasted and finely chopped. Small packets or sachets of Gutka are held in the mouth, sucked or chewed.33
Khiwam (qimam) is a dried paste made from tobacco extract, spices and additives that is chewed by people in the Indian Subcontinent and South Asia. Additives such as musk and spices such as saffron, cardamom and aniseed may be found in Khiwam. Khiwam may be made using tobacco leaves from the Nicotiana rustica plant, instead of the more common N. tabacum. N. rustica which often contains high amounts of nicotine.33
Loose-leaf is loose cigar tobacco leaves that are air-cured, stemmed, cut or granulated, and loosely packed to form small strips of shredded tobacco. Loose-leaf has a high sugar content and liquorice is often added. It is chewed or held in place in the mouth.33
Mishri is made from tobacco that is baked or partially burnt on a hot metal plate and then powdered. Mishri is used in South Asia where it is applied to the teeth and gums.33
Moist snuff and snus Moist snuff is often used in Europe and North America, and is the most common form of smokeless tobacco in the USA. Moist snuff tobacco is air- or fire-cured and either fine-cut or long-cut into strips. The final product may contain up to 50% moisture.33
Snus is a Swedish type of moist snuff that consists of finely ground dry tobacco of Kentucky and Virginia tobacco varieties with aromatic and other additives.36 Additives may include aromatic substances, salts (sodium chloride), water, humidifying agents and chemical buffering agents (sodium carbonate). Snus may be used for 11–14 h per day.
Pituri/Mingkulpa In central Australia, some Aboriginal people chew products made from wild tobacco plants of various species. These products are known by a variety of names, such as Pituri or Mingkulpa. Pituri is prepared by breaking dried tobacco leaves into pieces, mixing with wood ash and chewing to form a 'quid'.37 A range of wood is burned to form the ash, such as species of Acacia, Grevillea and Eucalyptus. The tobacco may come from a range of the 22 native species and four sub-species of Nicotiana that are found in Australia.38 See Sections 8.2 and 8.5 for more information about Pituri use.
Plug is commonly used in North America. It is made from Burley and bright tobacco or cigar tobacco leaves from the top of the plant. The tobacco leaves are immersed in a mixture of liquorice or sugar, pressed into a plug and covered by a wrapper leaf. Moist plug is chewed or held in the mouth.33
Toombak is made from N. rustica and/or N. glauca and is commonly used in the Sudan.36 It’s made from dried tobacco leaves that are tied into bundles, sprinkled with water and fermented at 30–45°C for a couple of weeks.33 These leaves are ground and matured for up to 1 year. Matured leaves are mixed with sodium bicarbonate and blended by hand until becoming moist and hardened. Balls of Toombak are held in the mouth and sucked for 10–15 minutes. Toombak contains very high amounts of carcinogenic N-nitrosamines.36
Twist/roll is a chewing tobacco sold in North America. It is made from dark, air- or fire-cured Burley tobacco leaves. These are treated with a tar-like tobacco leaf extract and flavourants are added. The product is twisted into rope-like strands and dried.33
In addition to the above, there are numerous other smokeless products that incorporate tobacco with other major ingredients.
Relevant news and research
For recent news items and research on this topic, click here. ( Last updated March 2023)
1. World Health Organization. WHO Framework convention on tobacco control. Geneva: WHO, 2003. Available from: http://apps.who.int/iris/bitstream/handle/10665/42811/9241591013.pdf;jsessionid=8D28335A9D60D63D78BE79F59EA44809?sequence=1.
2. National Cancer Institute. Cigar smoking and cancer.: NIH, 2010. Available from: https://www.cancer.gov/about-cancer/causes-prevention/risk/tobacco/cigars-fact-sheet.
3. McMurtrey JE. Tobacco plant species. Britannica, 2015. Available from: https://www.britannica.com/plant/common-tobacco.
4. Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR). Addictiveness and attractiveness of tobacco additives. Brussels, Belgium 2010. Available from: http://ec.europa.eu/health/scientific_committees/emerging/docs/scenihr_o_031.pdf.
5. Anthony P and Bowles CP. From seed to smoke: A cigar's odyssey. Davidoff cigar factory & farms (How cigars are made), 2019. Available from: https://www.youtube.com/watch?v=_mGFeOwjfbs&lc=UgxaLjiCxzvxLIKxZax4AaABAg.
6. Rosenberry ZR, Strasser AA, Canlas LL, Potts JL, and Pickworth WB. Make your own cigarettes: characteristics of the product and the consumer. Nicotine & Tobacco Research, 2013; 15(8):1453-7. Available from: https://www.ncbi.nlm.nih.gov/pubmed/23296210
7. Kaiserman MJ and Rickert WS. Handmade cigarettes: it's the tube that counts. American Journal of Public Health, 1992; 82(1):107-9. Available from: https://www.ncbi.nlm.nih.gov/pubmed/1536311
8. Ericksen AB. What is the difference between RYO and pipe tobacco? CStore Decisions, 2021. Available from: https://cstoredecisions.com/2021/04/19/what-is-the-difference-between-ryo-and-pipe-tobacco/
9. Laugesen M, Epton M, Frampton CM, Glover M, and Lea RA. Hand-rolled cigarette smoking patterns compared with factory-made cigarette smoking in New Zealand men. BMC Public Health, 2009; 9(1):194. Available from: https://www.ncbi.nlm.nih.gov/pubmed/19538719
10. SCENHIR. Tobacco Additives. 2010. Available from: https://ec.europa.eu/health/scientific_committees/opinions_layman/tobacco/en/about.htm#7.
11. Ayo-Yusuf OA and Olutola BG. 'Roll-your-own' cigarette smoking in South Africa between 2007 and 2010. BMC Public Health, 2013; 13:597. Available from: https://www.ncbi.nlm.nih.gov/pubmed/23800007
12. Morris DS and Tynan MA. Fiscal and policy implications of selling pipe tobacco for roll-your-own cigarettes in the United States. PloS One, 2012; 7(5):e36487. Available from: https://www.ncbi.nlm.nih.gov/pubmed/22567159
13. Staunton D. Letter to Michael Wooldridge, Minister for Health and Family Services. 1998. Available from: https://www.industrydocuments.ucsf.edu/tobacco/docs/#id=rnfh0101
14. Bittoun R. The medical consequences of smoking “chop-chop” tobacco 2004. Available from: https://web.archive.org/web/20110602194636/http:/www.health.gov.au/internet/main/publishing.nsf/Content/927F4224C3D9E1A6CA25700D0018284B/$File/chopchop.pdf.
15. Bittoun R. "Chop-chop" tobacco smoking. Medical Journal of Australia, 2002; 177(11-12):686-7. Available from: https://www.ncbi.nlm.nih.gov/pubmed/12464004
16. Materials and Contruction. Pipedia, 2021. Available from: https://pipedia.org/wiki/Materials_and_Construction.
17. Watson S. Effects of smoking pipes and cigars. 2020. Available from: https://www.webmd.com/smoking-cessation/effects-of-smoking-pipes-and-cigars.
18. Stanion C. Know your tobacco cuts. 2020. Available from: https://www.smokingpipes.com/smokingpipesblog/single.cfm/post/know-your-tobacco-cuts.
19. Ericksen AB. What Is the Difference Between RYO and Pipe Tobacco? 2021. Available from: https://cstoredecisions.com/2021/04/19/what-is-the-difference-between-ryo-and-pipe-tobacco/.
20. Corey CG, Ambrose BK, Apelberg BJ, and King BA. Flavored tobacco product use among middle and high school students--United States, 2014. Morbidity and Mortality Weekly Report, 2015; 64(38):1066-70. Available from: https://www.ncbi.nlm.nih.gov/pubmed/26421418
21. Maziak W, Ward KD, and Eissenberg T. Interventions for waterpipe smoking cessation. Cochrane Database of Systematic Reviews, 2007; (4):CD005549. Available from: https://www.ncbi.nlm.nih.gov/pubmed/17943865
22. Williams T and White V. What factors are associated with electronic cigarette, shisha-tobacco and conventional cigarette use? Findings from a cross-sectional survey of Australian adolescents? Substance Use & Misuse, 2018; 53(9):1433-43. Available from: https://www.ncbi.nlm.nih.gov/pubmed/29336657
23. Carroll T, Poder N, and Perusco A. Is concern about waterpipe tobacco smoking warranted? Australian and New Zealand Journal of Public Health, 2008; 32(2):181-2. Available from: https://www.ncbi.nlm.nih.gov/pubmed/18412692
24. Cobb C, Ward KD, Maziak W, Shihadeh AL, and Eissenberg T. Waterpipe tobacco smoking: an emerging health crisis in the United States. American Journal of Health Behavior, 2010; 34(3):275-85. Available from: https://www.ncbi.nlm.nih.gov/pubmed/20001185
25. Waziry R, Jawad M, Ballout RA, Al Akel M, and Akl EA. The effects of waterpipe tobacco smoking on health outcomes: an updated systematic review and meta-analysis. International Journal of Epidemiology, 2017; 46(1):32-43. Available from: https://www.ncbi.nlm.nih.gov/pubmed/27075769
26. Shihadeh A. Investigation of mainstream smoke aerosol of the argileh water pipe. Food and Chemical Toxicology, 2003; 41(1):143-52. Available from: https://www.ncbi.nlm.nih.gov/pubmed/12453738
27. American Lung Association. An emerging deadly trend: waterpipe tobacco use. 2007. Available from: https://www.lung.org/getmedia/ec1a184f-0fc9-4a08-a83b-5f56b5f35eaf/2007-tobacco-policy-trend.pdf.pdf.
28. Campaign for Tobacco Free Kids. Kreteks in Indonesia 2009. Available from: https://www.tobaccofreekids.org/assets/global/pdfs/en/IW_facts_products_Kreteks.pdf.
29. Gudang Garam Tbk. Types of kretek. Indonesia Available from: https://www.gudanggaramtbk.com/en/kretek/.
30. Centers for Disease Control and Prevention. Bidi use among urban youth -- Massachusetts, March-April 1999. 1999. Available from: https://www.cdc.gov/mmwr/preview/mmwrhtml/mm4836a2.htm.
31. Gupta PC and Asma S. Bidi smoking and public health. Nee Delhi: Ministry of Health and Family Welfare, Government of India, 2008. Available from: https://www.healis.org/pdf/special-report/Bidi_smoking_and_public_health.pdf.
32. Food & Drug Administration. PMTA cover sheet: Technical project lead review for IQOS Tobacco Heating System (THS). FDA, 2017. Available from: https://www.fda.gov/media/124247/download.
33. International Agency for Research on Cancer. IARC monographs on the evaluation of carcinogenic risks to humans: Smokeless tobacco and some tobacco-specific N-Nitrosamines. 89 Lyon, France: IARC, 2007. Available from: https://publications.iarc.fr/Book-And-Report-Series/Iarc-Monographs-On-The-Identification-Of-Carcinogenic-Hazards-To-Humans/Smokeless-Tobacco-And-Some-Tobacco-specific-Em-N-Em--Nitrosamines-2007.
34. Chapman S and Wakefield M. Tobacco control advocacy in Australia: reflections on 30 years of progress. Health Education and Behavior, 2001; 28(3):274-89. Available from: https://www.ncbi.nlm.nih.gov/pubmed/11380049
35. International Agency for Research on Cancer, Personal habits and indoor combustions. IARC Monographs Vol. Volume 100 E A review of human carcinogens.Lyon, France: IARC; 2012. Available from: https://www.ncbi.nlm.nih.gov/books/NBK304391/.
36. Idris AM, Ibrahim SO, Vasstrand EN, Johannessen AC, Lillehaug JR, et al. The Swedish snus and the Sudanese toombak: are they different? Oral Oncology, 1998; 34(6):558-66. Available from: https://www.ncbi.nlm.nih.gov/pubmed/9930371
37. Ratsch A, Steadman KJ, and Bogossian F. The pituri story: a review of the historical literature surrounding traditional Australian Aboriginal use of nicotine in Central Australia. Journal of Ethnobiology and Ethnomedicine, 2010; 6:26. Available from: https://www.ncbi.nlm.nih.gov/pubmed/20831827
38. Ratsch A, Steadman K, Ryu B, and Bogossian F. Tobacco and pituri use in pregnancy: A protocol for measuring maternal and perinatal exposure and outcomes in Central Australian Aboriginal Women. Methods and Protocols, 2019; 2(2). Available from: https://www.ncbi.nlm.nih.gov/pubmed/31181680