As explained in Chapter 1, many types of cigars1 are available to U.S. consumers. This chapter describes the physical characteristics of various types, including “premium cigars”;2 reviews what is known about the chemistry of cigar tobacco and smoke; discusses biomarkers of product use; considers inhalation patterns of cigar users; and briefly examines flavorings. See Chapter 5 for information on secondhand emissions from premium cigars. As illustrated in the report’s framework (see Figure 1-1 in Chapter 1), these characteristics of premium cigars influence both patterns of use and marketing and risk perceptions. Published data on premium cigars specifically is lacking in many areas; in those cases, the committee relied on studies of large cigars when possible, on the 1998 National Cancer Institute (NCI) monograph on cigars (which, as noted in Chapter 1, is the only comprehensive review of all cigar types), and on committee expertise when extrapolating results and implications to premium cigars. This chapter was guided by research questions from Food and Drug Administration (FDA) and National Institutes of Health (NIH) about cigar manufacturing processes, chemical constituents of tobacco and smoke,
1 Note that when the terms “cigar(s)” or “cigars in general” are used in this report, they refer to all cigar types (filtered cigars, little cigars, cigarillos, and large/traditional cigars [which include premium cigars]). When discussing a specific cigar type, the type is noted in text.
2 Note that quotations are used at the first occurrence of the term “premium” in each chapter, as there is no formally agreed upon definition of what constitutes a premium cigar, and different entities might use this term differently. See Chapter 1 for more information.
and smoking topography; see Appendix A for the full listing of research questions. Conclusions are provided throughout the chapter; a listing of all conclusions by chapter is available in the Summary.
As noted in Chapter 1, federal regulations define a cigar as “any roll of tobacco wrapped in leaf tobacco or in any substance containing tobacco.”3 At the most basic level, the major regulatory difference between cigars and cigarettes is the wrapper; while a cigar uses a tobacco leaf or material containing tobacco (often referred to as “reconstituted tobacco” or “homogenized tobacco leaf”4), a cigarette has paper or a material that does not contain tobacco. Mass-produced cigarettes usually have filters, whereas most cigars do not, with a few notable exceptions like filtered cigars. Additionally, cigar filler, binder, and wrappers are predominantly air-cured and fermented tobacco, in contrast to cigarettes, which commonly use a blend of Virginia tobacco (also known as “Bright” tobacco; flue-cured), Burley tobacco (air-cured), and Turkish/oriental tobacco (sun-cured); expanded and reconstituted tobacco are also used in cigarettes (NCI, 1998; Philip Morris International, n.d.). Exceptions to this are some little cigars, which tend to use some flue-cured and/or Turkish tobacco, presumably to be more appealing to cigarette users (Delnevo and Hrywna, 2007). Cigar tobacco undergoes fermentation, which can be a multistep process that lasts months or even years for premium cigars. These differences in the manufacturing process (e.g., the fermentation process) typically result in higher nitrate levels in the tobacco and a higher (alkaline) pH of cigar smoke than cigarette smoke, which has important implications for nicotine absorption orally and by inhaling. At an alkaline pH, some of the nicotine in cigar smoke is unprotonated; this form of nicotine is readily absorbed by the oral mucosa. Alkaline smoke is also harsh and more difficult to inhale, affecting patterns of smoke inhalation into the lungs (Henningfield et al., 1999; NCI, 1998). The form of nicotine present in acidic smoke, as generally found in cigarettes, is not easily absorbed by oral mucosa, and inhalation is required for efficient nicotine absorption; it is also generally less noxious to inhale. The relationship between tobacco pH and smoke pH is complex and not fully understood, especially for premium cigars. Few studies address the pH of cigar smoke, and it can be difficult to measure. Smoke pH measurements can be affected by the measurement method and by relative humidity and
3 26 U.S.C. Sec. 5702a.
4 Reconstituted tobacco or homogenized tobacco leaf is a mixture of an adhesive with the ground remnants of tobacco that remain after manufacture. The malleable sheets of “recycled” tobacco can then be used in various tobacco products (Cigar Aficionado, n.d).
The cigar marketplace is highly diverse, including little/filtered cigars, cigarillos, large nonpremium cigars, and premium cigars (see Figure 2-1). Despite the wide variety of products, as noted in Chapter 1, no universally accepted classification system exists. The 1998 NCI monograph used four groups (see Table 1-1 in Chapter 1), which is useful because it illustrates the wide variety in the cigar marketplace. Each of these categories is described briefly below.
Little cigars are filtered, frequently sold in packs of 20, and weigh less than 3 pounds per 1,000 cigars, or 1.36 g per stick (TTB, 2017). They are made on the same machines as cigarettes and are similar in size and shape. The main difference is the wrapper. Whereas cigarettes are wrapped in paper, little cigars are almost always wrapped in reconstituted tobacco. The amount of tobacco in that wrapper has been observed by some, including the tobacco industry, to be minimal in most cases (Delnevo and Hrywna, 2007). Since the early 1970s, little cigars have been marketed to cigarette users as substitutes for cigarettes (Delnevo and Hrywna, 2007; Delnevo et al., 2017b). In 2009, in response to changes in federal tobacco excise tax, many little cigar manufacturers modified their products and made them slightly longer and heavier to meet the large cigar tax classification and the lower federal excise tax (CDC, 2012; Delnevo et al., 2017b). A recent evaluation of several common little and large filtered cigars found many similarities between filtered cigars and cigarettes and minor (but statistically significant) difference in weight between little cigars and large filtered cigars (Caruso et al., 2015). For this reason, they are discussed as one grouping of cigars, consistent with prior research (Corey et al., 2014, 2018).
Given their similarities to cigarettes, it is not surprising that the pH levels of little/filtered cigars are likewise similar. Henningfield and colleagues (1999) tested four little cigars and found the pH of the tobacco filler ranged from 5.7 to 6.1; they concluded that these products closely resembled typical cigarettes. Lawler and colleagues (2017) tested more than 100 cigarettes, little cigars, cigarillos, and cigars (the committee identified 13 large cigars and 2 cigarillos as premium based on brand name and committee definition)5 and found the mean pH for cigarette tobacco in aqueous solution was 5.46, whereas it was 5.72 for the little/filtered cigar tobacco. Moreover, of the 14 little/filtered cigars tested, the pH ranged from 5.24 to 6.11 and all but one brand had a pH below 6.0 (Lawler et al., 2017).
Flavorings in cigarettes are banned, but filtered cigars may be flavored. When the Tobacco Control Act was signed in 2009, one brand of clove cigarettes, Djarum, changed its wrapper and rebranded its product as a filtered cigar to circumvent the flavor ban on cigarettes (Delnevo and Hrywna, 2015). Some of the most popular brands of little or filtered cigars in the United States are Cheyenne, Swisher Sweets, Primetime, and Djarum (Corey et al., 2018; Delnevo et al., 2017a, 2021).
5 The authors’ cigar classification was based on product labeling.
As with the other cigar types, the term “cigarillo” has no formal definition, but these products are commonly understood by consumers and researchers to be medium-sized, machine-made cigars that may have plastic or wood tips. The wrapper is often reconstituted tobacco, but rough “natural leaf” wrappers have recently become a popular characteristic, driving sales (Vonder Haar, 2021). The 1998 NCI monograph describes these cigars as weighing 1.3–2.5 grams (NCI, 1998), but more recent measurements suggest a wider and higher weight range. For example, Henningfield and colleagues (1999) reported the weight of three cigarillos in their sample: 2.26–3.37 grams. Koszowski and colleagues (2018) tested 10 popular cigarillos, which were 1.64–4.24 grams, with a mean weight of 2.86 grams. Likewise, recent testing commissioned by this committee of 23 popular cigarillos, representing five brands (Black & Mild, Swisher Sweets, Backwoods, Dutch Masters, and Garcia y Vega) were 2.1–3.2 grams, with a mean weight of 2.8 grams (Yassin et al., 2021); see Appendix F for more information. The typical weight likely falls more closely between 2.5 and 3.5 grams (see Appendix F). Notably, 2.72 grams translates to 6 pounds per 1,000 units, a threshold that has been proposed for a premium cigar product.
Small samples from Henningfield and colleagues (1999) (3 cigarillos) and Koszowski and colleagues (2018) (10 cigarillos) found a mean pH for cigarillo tobacco filler of 6.1 and 6.39, respectively. Lawler and colleagues (2017) measured 21 cigarillos (including what they refer to as “mini” cigarillos) and reported a mean pH of tobacco in aqueous solution of 5.7; the two cigarillos with the highest pH were determined by the committee to be premium cigars. The authors noted that cigars made with pipe tobacco had the lowest pH (5.05) (Lawler et al., 2017). The bestselling cigarillo brand in the United States, Black & Mild, is made exclusively with pipe tobacco. Koszowski and colleagues (2018) also found a low pH for this brand.
Cigarillo products tend to be flavored, with fruity, sweet, and alcoholic beverage flavors being the most common (Delnevo et al., 2017a, 2021; Lawyer et al., 2019). Moreover, wood tip cigarillos are growing in popularity; the tip itself can be sweetened and flavored (Erythropel et al., 2018). The two most popular brands of cigarillos are Black & Mild and Swisher Sweets, which have for decades held the majority of the market; other popular brands are White Owl, Garcia y Vega/Game, and Backwoods (Corey et al., 2018; Delnevo et al., 2017a, 2021; NCI, 1998).
Large Nonpremium Cigars
Large cigars are, for tax purposes, those that weigh more than 1.36 grams (TTB, 2017). This broad weight category includes filtered cigars and cigarillos. Despite the similar lack of formal definition, the term is commonly understood as nontipped, machine-made cigars that tend to be larger than cigarillos. Large cigars typically have three components: wrapper, binder, and filler. The wrapper is often made from reconstituted tobacco leaf. The 1998 NCI monograph describes these as weighing 5–17 grams and measuring 110–150 mm (NCI, 1998). Koszowski and colleagues (2018) tested large cigars and found the mean weight was 7.16 grams, which was notably greater than the cigarillos they assessed (2.86 grams). Additionally, the large cigars were longer (mean length = 140 mm) than the cigarillos (110 mm). However, they potentially misclassified some conventional cigarillos as large cigars, as their classification was based on product labeling.
Koszowski and colleagues (2018) found a mean pH for large cigar tobacco filler of 6.53, which did not notably differ from the cigarillos. While Lawler and colleagues (2017) measured 27 “large cigars,” Koszowski and colleagues (2018) relied on product labeling. Many products measured by Lawler and colleagues would be conventionally classified as filtered cigars (e.g., Santa Fe Filtered Cigars in a 20 pack) or cigarillos (e.g., Backwoods Wild Rum). Several of the remaining “large cigars” were premium cigar brands and matched the committee’s definition of a premium cigar. The lowest-pH “large cigars” as measured by Lawler and colleagues (2017) were filtered cigars or cigarillos.
Like cigarillo products, machine-made large cigars also tend to be flavored (Delnevo et al., 2017a, 2021). The most popular brands of large cigars are Black & Mild,6 Swisher Sweets, White Owl, Garcia y Vega, and Dutch Masters (Corey et al., 2018; Delnevo et al., 2017a, 2021; NCI, 1998). Size and the presence or absence of wood or plastic tips tend to be arbitrary dividing lines between cigarillos and large cigars; some research has combined machine-made cigarillos and large cigars (Corey et al., 2014).
6 Consumers and researchers may refer to Black & Mild products as cigarillos and/or filtered cigars, but they are large cigars for federal tax purposes. As Chapter 1 notes, no formal definitions exist for any cigar types (other than the large and small cigar taxation categories); therefore, the industry can name products without restriction, and consumers may have different ideas of product classification. Consequently, there is overlap in the popular brands listed for each type of cigar described in this chapter.
This report employed a definition that provides a dividing line between premium cigars and the machine-made filtered cigars, cigarillos, and large cigars described previously. In comparison to other cigars, premium cigars are handmade; consist of 100 percent tobacco leaf wrapper; contain long filler tobacco; do not use a filter, tip, or mouthpiece; and are larger and heavier. While flavors are common in the machine-made cigar marketplace, additives and flavors are rare in the premium market, with exceptions (Corey et al., 2018). The committee definition of premium cigars does not allow for flavors or additives; however, particular premium cigars brands do have distinctive aromas and tastes that are partially attributed to the fermenting, blending, and aging of the tobacco (see the section on flavors later in this chapter for more information).
While weight is not as commonly referred to in definitions and is not intrinsic to a cigar being premium, the cut point of 6 pounds per 1,000 units is the weight most commonly used, as noted in Chapter 1. Premium cigars have been described as 5–22 grams (Henningfield et al., 1999; NCI, 1998). The research literature rarely refers to the cigars being tested as premium. Therefore, the summary provided here relies on the premium cigar brands noted throughout this report. Henningfield and colleagues’ (1999) study included three cigar brands that are considered premium: Cuesta Rey, Macanudo, and Nat Sherman. With the exception of the Cuesta Rey Cameo (described in the paper as a “cigarillo”), their weight was considerably higher than the cigar types previously described; two of them were more than 20 grams. In the Koszowski and colleagues (2018) study, one of the large cigars was premium: a Romeo y Julieta 1875 Churchill, which weighed 17.60 grams. Recent testing commissioned by the committee of 66 premium cigars from several top premium cigar brands highlights that these products are quite large and considerably exceed 6 pounds per 1,000 units (Yassin et al., 2021), indicating that this weight criterion commonly used in definitions of premium cigars may need to be re-examined, and possibly increased, to be consistent with the current marketplace (see Table 2-1 and Appendix F for more information). The most popular brands of premium cigars are Cohiba, Macanudo, Arturo Fuente, and Montecristo (Corey et al., 2018); other popular brands are detailed in Table 2-1.
Finding 2-1: There is a wide variety of cigar products overall, and within the category of premium, on the market, which differ with respect to size and weight. Many of the cigars considered premium weigh considerably more than 6 pounds per 1,000 units.
TABLE 2-1 Summary of Characteristics of a Sample of Premium Cigars
|Number of Cigars Measured||Mean Weight (g)||Mean Length (mm)||Mean Diameter (mm)||Mean Pounds per Thousand|
|La Gloria Cubana||5||14.8||137.0||19.0||32.7|
|Romeo y Julieta||4||15.1||133.0||19.8||33.2|
NOTES: N = 66. g = gram; mm = millimeter.
SOURCE: Yassin et al., 2021.
All cigar tobaccos, like all cigarette and smokeless tobaccos, contain the highly addictive compound nicotine and carcinogenic tobacco-specific nitrosamines (NCI, 1998). When tobacco is burned during smoking, the tobacco-specific nitrosamines are transferred to the smoke and a plethora of new carcinogens and toxicants, including polycyclic aromatic hydrocarbons (PAH), such as benzo[a]pyrene (BaP), and volatiles, such as formaldehyde, acrolein, and 1,3-butadiene, are formed. The user is exposed to this carcinogenic mixture.
It is difficult to quantify constituents of cigar smoke because of the lack of standardization of measurement conditions. This is particularly true for large cigars, including premium cigars. As discussed in Cooperation Centre for Scientific Research Relative to Tobacco (CORESTA, a tobacco industry association) documents and in presentations to the committee, the varying sizes and shapes of cigars, as well as their sometimes uneven combustion properties, make smoke measurements challenging (CORESTA, 2021; Lindegaard, 2021; Watson, 2021).
However, these challenges do not exist for the uncombusted tobacco; well-standardized procedures exist for tobacco analysis involving isotopically labeled internal standards, extraction with suitable solvents, partial purification and enrichment of analytes, and quantitation by gas chromatography-mass spectrometry (GC-MS) or liquid chromatography-mass spectrometry (LC-MS), and related well-established and validated analytical chemistry techniques. Thus, highly reliable analytical data on constituents of cigar tobacco are available. These are partially transferred to smoke during smoking and are also the substrates for pyrosynthesis of new toxicants.
This section begins with a retrospective overview of the comprehensive NIH-sponsored review of the health effects of cigars (NCI, 1998), then proceeds to the relevant literature published since. The committee’s literature search identified 243 references that could have been related to this topic. Each reference was considered, and the conclusions of the relevant studies are described here.
Overview of Chemistry and Toxicology Findings from 1998 NCI Monograph on Cigars
Chapter 3 of the 1998 NCI monograph, on chemistry and toxicology, compared selected components of cigar tobacco (including some premium cigars) and types of cigarette tobacco; relevant data are discussed here.
The report compared levels of certain constituents in cigar tobacco to four types of cigarette tobacco: Burley, Maryland, Bright (Virginia), and Oriental (data expressed as percent dry weight of tobacco). The constituents included nicotine, nitrate, total polyphenols, paraffins, reducing sugars, neophytadiene, phytosterols, and oxalic, maleic, and citric acids. Nicotine concentrations were similar in the different tobacco types. Some constituent differences were noted, and these were believed to be related to the long aging and fermentation process used in cigar manufacturing. Cigar tobacco contained much lower levels of polyphenols and somewhat lower levels of phytosterols but higher levels of nitrate than the cigarette tobacco types other than Burley (which is a main constituent of cigars). Reducing sugars were higher in Bright tobacco than in cigar tobacco and
the other cigarette tobacco types. The pH of cigar tobacco (6.9–7.8) was higher than that of the cigarette tobacco types (4.4–7.5).
Further comparisons focused on nitrate and tobacco-specific nitrosamines. Tobacco nitrate is the precursor to nitrite in tobacco, and the latter reacts with tobacco alkaloids during curing and processing to produce tobacco-specific nitrosamines, arguably the most carcinogenic constituents occurring in relatively high quantities in unburned tobacco, including cigar tobacco. The most carcinogenic compounds among the tobacco-specific nitrosamines, based on extensive laboratory testing in animals, are N’-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), and these are considered “carcinogenic to humans” by the International Agency for Research on Cancer (IARC, 2007). NNN in particular is highly relevant to the health effects of cigars because it is a powerful oral cavity and esophageal carcinogen in rats when given in drinking water, while a mixture of NNN and NNK also produced oral and lung cancers in rats when applied in the oral cavity (Balbo et al., 2013; Hecht et al., 1986). Similar concentrations of NNN and total tobacco-specific nitrosamines (NNN, NNK, N’-nitrosoanatabine and N’-nitrosoanabasine) have been found in all tobacco types of little cigars, nonfilter cigars, filter cigarettes, and nonfilter cigarettes (NCI, 1998).
Further comparisons explored the comparative smoke profiles of cigarettes and cigars, including premium cigars. Premium and other cigar smoke have been found to deliver amounts of tar, carbon monoxide (CO), nitrogen oxides, nicotine, NNN, NNK, acrolein, acetaldehyde, benzene, isoprene, BaP and other PAH, hydrogen cyanide, metals, nitrogen oxides, and other potentially toxic constituents generally comparable to or greater than cigarettes (when expressed per gram of tobacco smoked) (NCI, 1998). However, these comparisons are complex because of the different physical characteristics of cigarettes and cigars and the different machine smoking conditions used. Additionally, smoke pH changes differentially over time for different tobacco products (see Figures 2-2 and 2-3) (Brunnemann and Hoffmann, 1974; Henningfield et al., 1999; NCI, 1998). For example, one study found that the smoke pH of cigarettes decreased from 6.0 at the third puff to 5.7 at the last. In contrast, little cigar smoke pH changed from 6.5 to 7.4 from third to last puff, and cigar smoke pH increased from 6.5 at the third puff to 8.0 at the last (Brunnemann and Hoffmann, 1974; NCI, 1998). As described, these changes are important because tobacco smoke above pH 6.0, as is generally observed in cigars, contains greater proportions of unprotonated nicotine, which affects puffing topography (the pattern of inhalation by a user) and increases oropharyngeal nicotine absorption (Henningfield et al., 1999; NCI, 1998).
The NCI monograph (1998, p. 97) chapter concluded
- “Cigar smoke contains the same toxic and carcinogenic compounds identified in cigarette smoke.
- When examined in animal studies, cigar smoke tar appears to be at least as carcinogenic as cigarette smoke tar.
- The differences in risk between cigarette smoking and cigar smoking appear to be related to the differences in patterns of use of those two tobacco products, principally nondaily use and less inhalation among cigar smokers, rather than a difference in the composition of the smoke.
- The amount of nicotine available as free, unprotonated nicotine is generally higher in cigars than in cigarettes due to the higher pH of cigar smoke. This free nicotine is readily absorbed across the oral mucosa, and may explain why cigar smokers are less likely to inhale than cigarette smokers.”
No new evidence in the current literature would significantly alter these conclusions.
Studies Published After the 1998 NCI Monograph on Cigars
Constituents of Cigar Tobacco
The studies reported here investigated constituents of cigar tobacco. Only a few of the studies mentioned premium cigars, specified countries of origin, or listed brand names that might identify some of the products as premium cigars.
As mentioned, Henningfield and colleagues (1999) studied nicotine concentration and smoke pH of various cigar brands, including “large premium cigar brands.” The tobacco content of the cigars ranged from 0.53 to 21.50 g, and the aqueous pH of the tobacco varied widely, from 5.7 to 7.9. The range of aqueous pH of the tobacco of the smaller cigars was 5.7–7.6, while that of the large cigars was 6.7–7.9. There was no clear relationship between tobacco pH and smoke pH overall. However, the smoke pH of smaller cigars became acidic after the first third of the cigar was consumed and remained acidic, while the larger cigars’ smoke pH, presumably including the premium cigars’, became acidic during the first third and then alkaline during the last third (Henningfield et al., 1999). Thus, nicotine and other constituents would be more readily absorbed through the buccal mucosa in the users of the large cigars, and not necessarily inhaled, particularly in the later puffs. This could relate to the
risk of oral cavity cancer in users of large cigars (see Chapter 5 for more information).
Ng and colleagues (2001) developed a GC-MS method to characterize nonvolatile organic acids in cigar tobacco, quantifying them in aqueous tobacco extracts by capture on strong anion exchange disks, followed by silylation and analysis. This method was applied to analyze 18 cigars from Cuba and 31 from other countries. Their identity as premium cigars was not specified. Principal component analysis of the acid profiles of all cigars showed separation of the two groups, indicating that acid profiles, including nicotinic, succinic, malic, citric, and pyroglutamic acids, are potentially useful in authenticating Cuban cigars.
In another study of cigar tobacco constituents, levels of free plus conjugated phytosterols in (unspecified) cigar tobacco were compared to flue-cured, Oriental, Burley, and Maryland tobacco. Phytosterols are potential precursors to PAH in smoke. Total phytosterols, the sum of stigmasterol, campesterol, and β-sitotsterol and their conjugates, were similar in Burley, Maryland, and cigar tobaccos, with higher levels in flue-cured and Oriental tobaccos (Liu et al., 2008).
Pappas and colleagues (2015) developed a new analytical method to determine concentrations of 10 toxic metals in little cigar tobacco using triple quadrupole inductively coupled plasma mass spectrometry: arsenic, beryllium, cadmium, chromium, cobalt, lead, manganese, nickel, selenium, and uranium. The results indicated no significant differences in analyte levels in little cigar versus cigarette tobacco, with the exception of nickel, which was lower in little cigar tobacco.
Fresquez and colleagues (2015) developed a validated method for the high-throughput determination of mercury in tobacco and mainstream smoke from little cigars. The method used a platinum trap and direct release for analysis by heating the trap in a mercury analyzer. The tobacco mercury levels were 17.9–24.9 nanogram per gram (ng/g) tobacco.
Limited data are available on the pH of premium cigar tobacco. As described above, Lawler and colleagues (2017) compared pH values and levels of nicotine in cigarette and cigar filler, including in cigars determined by the committee to be premium cigars. The range of mean pH of the large cigar filler in aqueous solution was 5.40–6.83; the range of mean filler pH of large cigars determined to be premium was 6.12–6.83. In this analysis, 73 percent (55 out of 75 brands) of the products had filler pH levels lower than 6.0. Of the 20 cigar tobacco products with the highest filler pH levels (mean pH >6), 85 percent (17) were large cigars, and 15 were determined to be premium cigars. In fact, all premium cigars had mean filler pH levels greater than 6.0. As described earlier in this chapter, alkaline pH results in more unprotonated nicotine and greater oral absorption of nicotine. However, the relationship between tobacco pH, which is more
easily measured, and smoke pH, which is more difficult to measure, is unclear (Henningfield et al., 1999; NCI, 1998). The authors found large cigars and cigarillos to have the highest mean nicotine concentrations when compared to little cigars, pipe tobacco cigars, and mini-cigarillos. The range of mean nicotine values in large cigars was 9.2–24.8 milligram per gram (mg/g) tobacco; the range of mean nicotine in those determined by the committee to be premium was 13.2–24.8 mg/g tobacco (Lawler et al., 2017). The nicotine values can be compared to the value given in the 1998 NCI monograph, 6.0–17.0 mg/g—in the same general range and extending beyond (NCI, 1998).
The committee commissioned an analysis of tobacco nicotine content in a convenience sample of premium cigars (see Appendix F). Nicotine in tobacco was analyzed using gas chromatography with nitrogen-phosphorous detector, using a modification of the CORESTA 62 method for determination of nicotine in tobacco and tobacco products by gas chromatographic analysis (CORESTA, 2020). A summary of findings is presented in Table 2-2.7 Overall, the analysis reveals that the average nicotine concentration was 19.91 mg/g of tobacco and varied from 8.51 to 33.26 milligrams (Yassin et al., 2021). Total nicotine content in the sample of premium cigars was 297.89 milligrams per cigar (varying from 98.62 to 629.26) (Yassin et al., 2021).
Finally, researchers quantified the levels of the tobacco-specific nitrosamines NNN and NNK in the tobacco of 60 commercial brands of little cigars (Edwards et al., 2021). The values were 1,440–12,100 ng/g tobacco for NNN and 26–2,950 ng/g tobacco for NNK. The NNN values are in the same range as that given in the 1998 NIH monograph, 2,940 ng/g. The relatively high levels of NNN and NNK are consistent with the high concentrations found in Burley tobacco, which is used in these products (Ding et al., 2008).
Although premium cigars were not the main focus of most of these studies, there is no reason to believe that the chemical profile of premium cigars would differ in important ways from those of other cigar types. They are all made from cigar tobacco (with the exception of little cigars, which can include tobacco blends [Delnevo and Hrywna, 2007]); the main concern is the tobacco and the resulting combustion, not the design of the cigar.
TABLE 2-2 Tobacco Nicotine Content in a Sample of Premium Cigars
|Number of Cigars Measured||Mean Weight (g)||Mean Nicotine Concentration (mg/g tobacco)||Total Nicotine per Premium Cigar (mg/stick)|
|K. Hansotia Gurkha||2||16.40||24.14||397.45|
|La Gloria Cubana||3||15.60||22.83||363.24|
|Romeo y Julieta||3||15.67||21.51||370.56|
NOTES: N = 44. g = gram; mg = milligram.
SOURCE: Yassin et al., 2021.
Constituents of Cigar Smoke
As noted, Fresquez and colleagues (2015) developed a validated method to determine mercury in tobacco and mainstream smoke from little cigars. Mercury levels in little cigar smoke under International Organization for Standardization/U.S. Federal Trade Commission (ISO/FTC) smoking conditions8 were 2.6–7.5 ng/cigar.
8 Two smoking conditions/methods are used by studies in this chapter. The Canadian Intense Regimen (CIR) includes 2-second puff duration, 55 milliliter (mL) puff volume, and 30-second interval (Minister of Justice, 2019), while the ISO/FTC regimen includes 2-second puff duration, 35 mL puff volume, and 60-second interval (ISO, 2012).
Klupinski and colleagues (2016) used two-dimensional gas chromatography-time of flight mass spectrometry to compare little cigar mainstream smoke with cigarette mainstream smoke. Among more than 25,000 components detected, the tricyclic terpenoid ambrox was unique to little cigars, and 3-methylbutanenitrile and 4-methylimidazole were more abundant in little cigar mainstream smoke, at levels of 0.4, 0.7, and 12 microgram per rod (µg/rod), respectively, than in cigarette smoke.
Hamad and colleagues (2017) compared levels of nicotine and certain harmful and potentially harmful constituents in mainstream, standard 3R4F reference cigarette smoke with those in the mainstream smoke of four popular little cigars under standardized smoking conditions. Under the Canadian Intense Regimen (CIR), nicotine levels in the smoke of the cigarette were higher than in the little cigars, while levels of NNK, NNN, and BaP were higher in little cigar than cigarette smoke, when expressed per mass of total particulate matter.
Cecil and colleagues (2017) quantified acrolein in mainstream smoke from sheet-wrapped cigars, also known as little cigars, versus commercial cigarettes. Of 15 sheet-wrapped cigars, the measured acrolein yields were 34.3–105 µg/product under the CIR, whereas yields in the smoke of 35 commercial cigarettes were 139–213 µg/product.
In a study of cigar burning under different smoking intensities and the effects of smoking conditions on emissions, researchers concluded that complex phenomena occur during cigar smoking that make emission data challenging to interpret and potentially misleading (Dethloff et al., 2017). This was attributed to the use of natural leaf, which is less processed and blended, and to physical variations of large cigars. They concluded that analysis of tobacco and physical parameters are a more sound foundation for product comparison than emission yields.
Reilly and colleagues (2018) quantified levels of seven carbonyls (formaldehyde, acrolein, propionaldehyde, crotonaldehyde, methyl ethyl ketone, acetaldehyde, and acetone) in the smoke of little cigars, filtered cigars (which the authors noted can be heavier and longer than little cigars), and cigarettes under the ISO/FTC and CIR methods of smoke generation. Per puff, levels of five of these were higher from little cigars than filtered cigars and cigarettes. Per unit, most carbonyl levels were higher from little cigars and filtered cigars than cigarettes using the ISO/FTC method, but only filtered cigars were higher using the CIR method.
Pickworth and colleagues (2018) compared mainstream smoke emissions from cigarillos and little cigars under human smoking topography conditions and found wide variability in these smoking patterns across subjects using both types of products. Toxicants measured included nicotine, NNK, NNN, BaP, 1,3-butadiene, acetaldehyde, and benzene. When adjusting for nicotine content, cigarillo mainstream smoke contained
more of all toxicants compared to little cigars; both product types delivered substantial levels of the measured toxicants.
Goel and colleagues (2018) quantified nicotine yields in the smoke of little cigars and filtered cigars (collectively called “small cigars” because of the lack of standard definitions and inconsistent classification of both products) and compared them to cigarettes. Nicotine yields in small cigars were higher under both ISO/FTC and CIR regimens than in cigarettes, but yields per puff were similar. The two types of small cigars did not differ.
In another study of carbonyls, levels of formaldehyde, acetaldehyde, acrolein, and crotonaldehyde delivery from 12 mass-market cigars were compared to those from 3R4F cigarettes (Jablonski et al., 2019). Per product, levels of acetaldehyde, acrolein, and crotonaldehyde were greater from cigar smoke than from mainstream cigarette smoke, but levels of formaldehyde were similar from both products.
Vu and colleagues (2021) determined the mainstream smoke yields of five volatile organic compounds—1,3-butadiene, acrylonitrile, benzene, isoprene, and toluene—in 60 commercial U.S. little cigars under the ISO/FTC and CIR smoking conditions. Higher yields were found under the CIR conditions. Little cigars produced higher mainstream smoke yields than cigarettes under both smoking regimens, and little cigar smoke contained higher amounts of these compounds than cigarette smoke when amounts were adjusted for the mass of tobacco.
Edwards and colleagues (2021) quantified levels of the tobacco-specific nitrosamines NNK and NNN in the smoke of 60 commercial little cigars using the ISO/FTC and CIR smoking conditions. NNK and NNN by the ISO nonintense smoking regimen were 89–879 and 200–1,540 ng/cigar, respectively, and 138–1570 and 445–2,780 ng/cigar under the CIR regimen. The average transfer of NNN from tobacco filler to mainstream smoke of little cigars was 10–18 percent, depending on the regimen, while that of NNK was 37–51 percent. Mainstream smoke yields of NNK and NNN from little cigars were 3–5 times higher than in commercial cigarettes.
Summary and Conclusions
In summary, vast amounts of data, much of it recent, exist on toxic and carcinogenic constituents of cigar tobacco and smoke demonstrating that all analyzed toxicant levels are similar or higher than those found in cigarette tobacco and smoke, when compared per unit of tobacco. These data clearly demonstrate that cigars could be as dangerous as or more dangerous than cigarettes, with respect to toxicant and carcinogen exposure per unit consumed. Despite only limited data on premium cigars, it is reasonable to expect that the results of analyses of tobacco and smoke
would not substantially differ from those of the products presented here because premium cigars’ tobacco and pyrolysis conditions are similar to those of other cigars. Thus, based on laboratory studies using validated analytical methods and a variety of smoking conditions, including human smoking topography conditions, the available data demonstrate that exposure of premium cigar users to toxic and carcinogenic constituents of smoke will be qualitatively similar to the exposure of users to constituents of other combustible tobacco products. The relationship between tobacco pH and smoke pH remains unclear, and smoke analysis in general can be challenging. However, two laboratory studies have shown cigar smoke pH becoming more alkaline from early to last puffs, which would result in more unprotonated nicotine and therefore more oral nicotine absorption.
Conclusion 2-1: There is conclusive evidence that the addictive, toxic, and carcinogenic constituents of cigar tobacco in general are the same as those present in cigarette tobacco. There is strongly suggestive evidence that constituents of premium cigar tobacco are similar to constituents of other cigars because all tobacco contains nicotine, carcinogenic tobacco-specific nitrosamines, metals, and precursors to toxic and carcinogenic compounds formed during the combustion process.
Conclusion 2-2: There is conclusive evidence that the toxicants and carcinogens in cigar smoke in general are qualitatively the same as those in cigarette smoke. There is no reason to believe that toxicants and carcinogens in premium cigar smoke are any different from those in other types of cigars. Additionally, it is likely that the total toxic and carcinogenic constituent yields will increase with the mass of tobacco filler in the cigar.
Conclusion 2-3: There is strongly suggestive evidence that there is a wide variety of pH levels of tobacco used in cigars overall; however, higher pH has been noted in premium cigar tobacco than for other cigar types. While there is insufficient evidence on the pH of premium cigar smoke, the pH of large cigar smoke is generally higher than cigarette smoke, which can decrease depth of inhalation and increase nicotine absorption through the oral mucosa. There is insufficient evidence on the relationship between the pH of premium cigar tobacco and smoke.
The previous section reviewed recent studies on potentially toxic and carcinogenic substances in cigar tobacco filler and smoke. The smoke concentrations were determined by machine measurements, which can be technically difficult, particularly for large cigars. Biomarkers of exposure,
substances detected in the urine, blood, saliva, and other body fluids, can potentially provide important information on human uptake and exposure under realistic conditions of product use. The following studies quantified various biomarkers in cigar users.
The tobacco alkaloids nicotine, anabasine, anatabine, nornicotine, and cotinine were quantified in the urine of subjects who smoked small cigars (Jacob et al., 1999). Levels were compared to those in the urine of users of cigarettes, smokeless tobacco, and pipes. The eight cigar users in the study used an average of five small cigars daily and excreted the lowest levels of all alkaloids except nornicotine. This was apparently the first report of systemic nicotine intake from regular cigar smoking. Cotinine levels were 1,740 µg/24 hour (h) in the cigar users compared to 3,360 µg/24 h in cigarette and 2,050 µg/24 h in smokeless tobacco users.
McDonald and colleagues (2002) measured inhalation of smoke from a “standard-sized” cigar using 99mTc-labeled sulfur colloid particles. There were 24 male volunteers; all had smoked cigars previously, and half were current or past regular cigarette users, while the other half had no history of cigarette smoking. Researchers devised a cigar holder allowing the smoke drawn from a standard-sized cigar to mix with the 99mTc-sulfur colloid aerosol particles along a plastic tube. A designed mouthpiece allowed each participant to inhale the mixed aerosol and smoke; imaging was performed after each subject smoked in the usual way for approximately 2 minutes in conjunction with the aerosol. Lung ventilation scanning was performed to assess inhalation. All subjects inhaled the cigar smoke to varying degrees, independent of whether they were also current or past cigarette users or exclusive cigar users.
The 1999–2012 National Health and Nutrition Examination Survey (NHANES) reported biomarkers of exposure among U.S. cigar users (Chen et al., 2014). After adjustment for age, sex, race and ethnicity, education, and body mass index, primary cigar users (those who smoked less than 100 cigarettes in their lives) had 138 times higher serum cotinine concentrations (6.2 ng/mL versus 0.045 ng/mL) and 18.9 times higher urinary 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) concentrations (19.1 picogram [pg]/mg creatinine versus 1.01 pg/mg creatinine) than nontobacco users. Cotinine is the main metabolite of nicotine, and NNAL is a metabolite of the tobacco-specific lung carcinogen NNK. This group also had higher blood cadmium and lead concentrations than nontobacco users. Similar results for serum cotinine, urinary NNAL, and blood cadmium and lead concentrations were observed in comparing secondary cigar users (who had smoked more than 100 cigarettes in their lifetime but were not currently doing so) to nontobacco users. Primary and secondary cigar users had significantly lower serum cotinine (geometric mean cotinine concentrations: 6.2 ng/mL and 24.2 ng/mL for
primary and secondary cigar users and 131.4 ng/mL for current cigarette-only users) and urinary NNAL concentrations than current cigarette-only users (19.1 pg/mg creatinine, 78.6 pg/mg creatinine, and 215.4 pg/mg creatinine, respectively).
Rosenberry and colleagues (2018) examined levels of plasma nicotine and exhaled CO in dual users who were randomized to smoke their own brand of cigarettes or a study-provided large cigar (Phillies Blunt; not a premium cigar). Both products significantly increased plasma nicotine and exhaled CO and significantly reduced the reported urge to smoke. They concluded that such dual users alter their smoking patterns so that they are exposed to similar levels of nicotine from both products and that the results challenge the idea that cigar smoking is less toxic than cigarette smoking.
Pickworth and colleagues (2017b) examined smoking topography and toxicant exposure (plasma nicotine and exhaled CO) in three groups of study participants who smoked both cigarettes and filtered little cigars, cigarillos, or large cigars (Phillies Blunt). All products resulted in similar plasma nicotine boost, but cigarillos and large cigars resulted in greater exhaled CO. These results indicate that biomarker data from cigar types can be quite different.
Koszowski and colleagues (2017) studied biomarkers in two groups of dual users who smoked their usual brand of cigarette and an unflavored little cigar or a cigarillo. The authors found significant differences in measures of puff topography, plasma nicotine, and exhaled CO after all three. Smoke deliveries, as determined by machine smoking under conditions that replicate human smoking, were similar for all three.
Pickworth and colleagues (2017a) studied smoking patterns and toxicant exposure after smoking a little cigar and a cigarette in dual users of these products. Plasma nicotine and exhaled CO increases were essentially identical after cigarette or little cigar smoking.
Claus and colleagues (2018) examined factors related to cigar smoking, including biomarkers of exposure in current exclusive cigar users. Adult exclusive cigar users (N = 77, aged 22–77 years, 16 female) were recruited and smoked their own brand product ad libitum for up to 1 hour; biomarkers of exposure, dependence symptoms, and smoking topography were assessed. The study design separated the groups into small (3 grams) and large (>3 grams) cigar users. The first group was subdivided into small cigars and cigarillos. Exclusive cigar users who smoked at least one cigar per week had measurable and variable urinary cotinine and total NNAL concentrations (see Table 2-3). Upon smoking a single cigar, plasma nicotine levels increased significantly overall and within each group (see Figure 2-4). Exhaled CO levels significantly increased following cigar smoking in all groups, including self-reporting noninhalers.
TABLE 2-3 Biomarkers of Exposure Associated with Ad Libitum Cigar Smoking
|All||Cigar Size||Cigarette Smoking History||Self-Reported Inhalation Behaviors|
|Cotinine (ng/mg creatinine)||469.0 (SD = 802.3)||640.4 (SD = 783.8)||695.2 (SD = 1,024.6)||297.6 (SD = 639.4)||87.3 (SD = 186.9)*||787.1 (SD = 967.5)*||657.5 (SD = 924.9)||320.0 (SD = 664.2)|
|Total NNAL (pg/mg creatinine)||418.3 (SD = 712.2)||859.0 (SD = 1,167.7)||552.7 (SD = 794.2)||201.1 (SD = 282.9)||84.2 (SD = 169.2)*||680.7 (SD = 856.1)*||665.2 (SD = 961.1)||213.5 (SD = 285.6)|
|Baseline plasma nicotine (ng/mL)||0.7 (SD = 0.9)||0.6 (SD = 0.4)||0.8 (SD = 1.4)||0.7 (SD = 0.7)||0.5 (SD = 0.0)||0.9 (SD = 1.2)||0.9 (SD = 1.2)||0.6 (SD = 0.5)|
|Nicotine Cmax (ng/mL)||10.2 (SD = 10.5)||5.8 (SD = 5.7)c||8.2 (SD = 7.1)||12.6 (SD = 12.5)a||8.4 (SD = 9.8)||11.7 (SD = 11.0)||13.2 (SD = 12.3)#||7.9 (SD = 8.5)#|
|Nicotine AUC0–120 (min x ng/mL)||742.3 (SD = 870.4)||343.6 (SD = 299.1)c||601.0 (SD = 559.9)||936.0 (SD = 1,055.6)a||613.1 (SD = 769.1)||848.8 (SD = 942.0)||989.7 (SD = 1,093.6)#||549.1 (SD = 591.2)#|
|All||Cigar Size||Cigarette Smoking History||Self-Reported Inhalation Behaviors|
|I-N Nicotine Cmax (ng/mL)||0.8 (SD = 1.3)||1.3 (SD = 1.3)c||1.3 (SD = 2.0)c||0.4 (SD = 0.4)a,b||0.4 (SD = 0.4)*||1.2 (SD = 1.7)*||1.3 (SD = 1.7)#||0.5 (SD = 0.6)#|
|I-N Nicotine AUC0–120 (min x ng/mL)||56.7 (SD = 91.8)||75.3 (SD = 64.0)||99.3 (SD = 148.8)c||28.7 (SD = 34.1)b||29.0 (SD = 35.4)*||79.5 (SD = 115.6)*||88.9 (SD = 124.6)#||31.4 (SD = 40.6)#|
|All||Cigar Size||Cigarette Smoking History||Self-Reported Inhalation Behaviors|
|T-N Nicotine Cmax (Cmax normalized by the amount of tobacco smoked [i.e., ng/mL/g tobacco])||4.1 (SD = 6.0)||4.9 (SD = 4.7)||6.7 (SD = 9.5)c||2.4 (SD = 2.7)b||2.3 (SD = 2.2)*||5.5 (SD = 7.6)*||6.1 (SD = 8.1)#||2.4 (SD = 2.8)#|
|T-N Nicotine AUC0–120 (AUC normalized by the amount of tobacco smoked [i.e., ng/mL/g tobacco])||287.5 (SD = 440.3)||285.3 (SD = 228.7)||494.8 (SD = 713.5)||179.3 (SD = 216.5)||166.9 (SD = 183.9)||386.9 (SD = 554.7)||439.7 (SD = 599.4)||168.6 (SD = 193.6)|
NOTES: Group means (SD) presented in the table represent the mean of the particular group without respect to the other group classifications. Statistically significant differences (p < .05) for cigar type are denoted with superscripts showing the relative group differences where a = small, b = cigarillo, and c = large; all follow-up comparisons are corrected for multiple comparisons using Tukey’s method for multiple comparisons (Tukey adjusted ps < .05). * = statistically significant difference (p < .05) between primary and secondary cigar smokers. # = statistically significant differences (p < .05) between self-reported inhalers and noninhalers. AUC = area under the concentration curve; AUC0-120 = area under the concentration curve from 0 to 120 minutes; Cmax = maximum observed concentration; g = gram; I-N = nicotine intake (consumed weight of cigar [g] x nicotine concentration [mg/g]); mg = milligram; mL= milliliter; ng = nanogram; NNAL = 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol; SD = standard deviation.
SOURCE: Claus et al., 2018.
Levels of biomarkers of exposure among U.S. adult cigar users in PATH Wave 1 have been reported (Chang et al., 2019). Biomarker data from 5,604 adults were available; the study authors compared geometric mean concentrations among cigar-only smokers (all cigars and separately for traditional cigars, cigarillos, and filtered cigars), cigarette-only smokers, dual cigar/cigarette smokers, and never-users of any tobacco product. Only 12 every day traditional cigar smokers participated, all of whom were male. Table 2-4 presents selected data for this group and comparator groups. Every day exclusive traditional cigar smokers were comparable with every day exclusive cigarette smokers for numerous biomarkers, including total NNAL (from NNK) and cyanoethyl mercapturic acid (from acrylonitrile), and slightly lower for total nicotine equivalents, 3-hydroxypropyl mercapturic acid (from acrolein), and 1-hydroxypyrene (from pyrene), but all of these and most of the other biomarkers in this group were substantially higher than in never-tobacco users, even for some day traditional cigar users.
Based on the measurement of urinary biomarkers of nicotine and toxicants and carcinogens in the large NHANES and PATH studies and several smaller controlled clinical studies examining different products, such as small and large cigars, cigar users are exposed to significant amounts of nicotine and harmful and potentially harmful constituents. While levels of some urinary biomarkers were higher in every day exclusive cigarette smokers, the PATH study found that, for other biomarkers, concentrations in every day exclusive traditional cigar smokers were comparable to those of every day exclusive cigarette smokers. This indicates similar exposure and uptake of nicotine, toxicants, and carcinogens. Concentrations of biomarkers were also higher than in never-tobacco users.
Conclusion 2-4: There is conclusive evidence that cigar smokers in general are exposed to significant amounts of nicotine and numerous harmful and potentially harmful constituents.
When assessing potential health risk associated with premium cigars, it is important to understand the pattern of exposure to nicotine and harmful chemicals inhaled. Such patterns of exposure could be affected by multiple factors, including product characteristics, such as cigar size, shape, and tobacco type (see the section at the beginning of this chapter) and the behavior of individual users. That behavior is characterized by not only the number of cigars smoked per day or month (see Chapter 3) but also the way an individual cigar is smoked, including the depth of inhalation and number of puffs taken per cigar. The health risks associ-
TABLE 2-4 Comparison of Selected Urinary Biomarkers in Every Day Exclusive Traditional Cigar Smokers and in Other Smokers and Never-Tobacco Users
|Urinary Biomarker Total nicotine equivalents (µmol/g creatinine)||Biomarker Source nicotine||Every Day Exclusive Traditional Cigar Smokers 24.05 (range = 12.85–45.00)||Some Day Exclusive Traditional Cigar Smokers 0.16 (range = 0.07–0.33)||Every Day Exclusive Cigarette Smokers 46.57 (range = 43.59–49.75)||Never-Tobacco Users 0.01 (range = 0.01–0.01)|
|Total NNAL (ng/g creatinine)||NNK||250.73 (range = 99.64–630.91)||8.68 (range = 5.23–14.41)||302.15 (range = 281.51–324.3)||0.92 (range = 0.82–1.04)|
|Cyanoethyl mercapturic acid (µg/g creatinine)||acrylonitrile||151.31 (range = 81.87–279.66)||5.31 (range = 3.89–7.26)||177.32 (range = 166.71–188.62)||1.27 (range = 1.2–1.36)|
|3-hydroxypropyl mercapturic acid (µg/g creatinine)||acrolein||666.62 (range = 455.34–975.92)||294.21 (range = 241.87–357.89)||1,396.05 (range = 1,313.86–1,483.37)||261.12 (range = 246.69–276.39)|
|1-hydroxypyrene (ng/g creatinine)||pyrene||177.78 (range = 117.63–268.69)||133.65 (range = 112.18–159.24)||336.44 (range = 320.03–353.7)||127.93 (range = 120.46–135.86)|
NOTE: g = gram; ng = nanogram; NNAL = 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol; NNK = 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone; µg = microgram; µmol = micromole.
SOURCE: Adapted from Chang et al., 2019.
ated with cigar smoke increases with frequency and intensity of smoking and the extent of inhalation (see Chapter 5).
Studies have shown that small cigars are often smoked and inhaled similarly to cigarettes (Pickworth et al., 2017a,b). However, determining how users puff on premium cigars and how deeply they inhale is challenging for many reasons. Unlike cigarette consumption, in which users typically light, puff rather consistently, and finish a cigarette in a single session, cigar users puff differently, take much longer to consume the product, and may not smoke the entire cigar in a single session. If so, the cigar is relit, and more of it is consumed. Another important challenge in measuring the puffing behavior of premium cigar users is the lack of commercially available instruments that can be used in research studies (Watson, 2021). Optimally, puffing behavior would be captured in natural settings that premium cigar smokers usually frequent. Puffing topography monitors would also be portable and ideally would not change the way a smoker usually uses a premium cigar. Most off-the-shelf commercial smoking topography instrumentation and hardware are designed for conventional cigarette research and need to be modified to accommodate cigars (Koszowski et al., 2017). The physical characteristics of cigarettes are consistent, unlike large cigars, which vary markedly in size and thus make standardization of measurements difficult (see the section at the beginning of this chapter and Appendix F for more information on variation in characteristics). Finally, alternative approaches to studying puffing topography, including direct observation by trained observers and video recordings, have not been commonly used to analyze inhalation patterns of premium cigar users. Although these methods minimize external influence on smoking characteristics, they cannot measure puff volume, an important index of smoke constituent intake (Blank et al., 2009).
Common measures of puffing topography include the number of puffs; the puff volume, duration, and velocity; interpuff interval; and time to smoke. Puffing topography is an index of toxicant exposure in cigarette smoking (Lee et al., 2003), making it an important measurement to understand the use behaviors of and toxicant exposure from large cigar smoking. A limited number of studies examine the smoking topography of large cigar users and the toxicant delivery from mainstream cigar smoke. The results of two clinical trials presented to the committee by Dr. Bartosz Koszowski are discussed next (Koszowski, 2021).
The first study was a published paper comparing large cigar and cigarette smoking use patterns, smoking topography, and toxicant exposure (Rosenberry et al., 2018). Dual users (n = 17, the majority of whom were men [n = 16] and African American [n = 13]) who smoked any brand of large cigar (≥1 per week) and cigarettes (≥10/day) were recruited.
In two laboratory sessions, they smoked ad libitum either their usual cigarette brand or a study-provided large cigar (Phillies Blunt). The order of tobacco products was randomized. The authors measured smoking topography in each session and collected plasma nicotine and exhaled CO before and after smoking.
Large cigars were smoked differently than cigarettes (Rosenberry et al., 2018). Participants smoked on average 1.49 grams of cigar, which was about 23 percent of the total weight. Interpuff interval was significantly shorter in large cigar smoking, while the number of puffs, puff volume, puff velocity, and time to smoke were significantly larger. According to the authors, these differences were in part due to the greater size of the large cigar than the cigarette (Rosenberry et al., 2018). However, cigar smoking had significant differences even among variables not reliant on product size (e.g., individual puff volume, puff velocity, and interpuff intervals), suggesting that the large cigars were smoked more vigorously (see Table 2-5).
Figure 2-5 illustrates an assessment of the temporal pattern of topography. The average of the first three and last three puffs found puff duration was significantly longer and interpuff interval was significantly shorter in the first three puffs for both products. Puff volume was greater
TABLE 2-5 One-way rANOVA Models of Outcomes Measures
|Cigarette Smoking||Large Cigar Smoking||Product F Value||Product p Value|
|Number of puffsa||12 (4)||23 (11)||54.2||<.001*|
|Total puff volume (mL)a||658 (215)||1,660 (1,060)||72.1||<.001*|
|Time to smoke (s)||252 (89)||371 (207)||8.0||.01*|
|Average puff volume (mL)||57.8 (20.4)||73.9 (20.0)||10.6||<.01*|
|Puff velocity (mL/s)a||23.6 (5.1)||34.3 (13.0)||20.6||<.001*|
|Puff duration (s)||2.6 (0.7)||2.5 (0.6)||0.8||.38|
|Interpuff interval (s)a||21.9 (9.8)||16.6 (9.6)||9.0||.01*|
NOTES: mL = milliliter; s = second; SD = standard deviation.
* Denotes significance at p < .05.
a log-transformed variable included in rANOVA model.
SOURCE: Rosenberry et al., 2018.
in the first three puffs for large cigars but similar for cigarettes (Rosenberry et al., 2018).
The study also found that both products significantly increased plasma nicotine and CO (see Table 2-6) (Rosenberry et al., 2018); the immediate increase implies significant large cigar smoke inhalation.
Overall, the study suggests that dual users of large cigars and cigarettes adapt their puffing behavior so that they are exposed to similar levels of nicotine from both products (Rosenberry et al., 2018). A similar smoking pattern and exposure profile was also found in another study of dual users of cigarillos and cigarettes who inhaled smoke from both in the same way, thus subjecting themselves to considerable amounts of nicotine and other smoke components (Koszowski et al., 2015). The authors concluded that, among dual users of large cigars and conventional cigarettes, exposure to smoke from large cigars may lead to or sustain nicotine addiction and produce health risks similar to those of cigarette smoking (Rosenberry et al., 2018). Lung cancer studies have elaborated on arguments about the effects of inhalation intensity and pattern on cancer development (see Chapter 5) (Doll and Peto, 1976; IARC, 2004).
The second study presented to the committee (unpublished) was a single-center, randomized, single-blinded, crossover trial that included 36 adult users of small (n = 18) and large (n = 18) cigars (Koszowski, 2021). It was designed to evaluate the relationship between tobacco pH, salivary
pH, and nicotine exposure in noninhaling cigar smokers. Assignment into study groups was based on participant report of the type of cigars they smoked and confirmation of the cigar size when participants brought their product to the laboratory for the in-person screening visit. An important methodological consideration was to limit cigar smoke exposure to buccal tissue—largely the mouth and upper pharynx—so participants complied with specific instructions given before and during the directed smoking sessions not to inhale. Two brands of large cigars were used: Dutch Master’s Palma (pH = 6.30) and White Owl NY Ranger (pH = 6.72). All participants in the large cigar group were male; the mean age was 46.1 years (range 22–64 years). Fifty percent of participants in the large cigar group identified as white. Large cigar participants reported using their products for a mean of 8.3 years and smoked an average of 16.5 cigars in the past 30 days. Only a few participants had measurable post-smoking nicotine concentrations in plasma. Most of the nicotine concentrations were undetectable by methods used in the study, but even when plasma nicotine could be quantified, the measured increases were small. Overall, this study suggests that exposure to nicotine among cigar users who smoked large cigars with acidic pH (<7.0) and did not inhale was minimal. This finding is consistent with a study by Gori and colleagues (1986), which found virtually no intake of nicotine through the buccal mucosa from cigarette smoke if it is kept in the mouth only and is not inhaled. It should be emphasized that the Koszowski (2021) study cited above did not include any large cigars with alkaline pH (>7.0). Since increased pH of smokeless tobacco has been shown to enhance nicotine absorption through buccal mucosa (Tomar and Henningfield, 1997), it is reasonably expected that increased alkalinity of a premium cigar could also promote oral nicotine absorption, even if emitted smoke is not inhaled.
The observation that dual users of cigars and cigarettes may be more likely to inhale deeply than exclusive users of cigars is also seen in differences in perceived level of inhalation reported by participants in the Cancer Prevention Study I of the American Cancer Society, conducted between 1959 and 1972. This was a prospective cohort study that followed more than 1 million individuals for 12 years (NCI, 1985, 1998). All users who participated self-reported levels of inhalation, using this subjective scale: none, slightly, moderately, or deeply. Figure 2-6 shows that individuals who inhale slightly or not at all made up the biggest portions of primary (never-cigarette user) and secondary cigar user rates. However, the study also revealed that secondary cigar users were more likely to report deep inhalation than primary cigar users (NCI, 1998).
Taken together, findings from these studies suggest that, compared to those who only smoke cigars, dual users of cigars and cigarettes are more prone to smoking cigars with a greater intensity, and therefore, inhaling
TABLE 2-6 2x2 rANOVA Models of Outcome Measures
|Mean (SD)||Product||Time||Product x Time Interaction|
|Outcome Measure||Cigarette Smoking||Large Cigar Smoking||F Value||p Value||F Value||p Value||F Value||p Value|
|Plasma nicotine (ng/mL)||<0.1||.98||32.2||<0.001*||0.7||0.42|
|Pre-smoking||18.0 (11.9)||20.7 (15.3)|
|Post-smoking||38.8 (15.3)||36.3 (23.0)|
|Pre-smoking||21 (12)||22 (14)|
|Post-smoking||30 (12)||47 (26)|
NOTES: COex = exhaled carbon monoxide; mL = milliliter; ng = nanogram; ppm = parts per million; SD = standard deviation.
* Denotes significance at p < .05.
a log-transformed variable included in rANOVA model.
SOURCE: Rosenberry et al., 2018.
the smoke more deeply (Koszowski et al., 2015; NCI, 1998; Rosenberry et al., 2018; Rostron et al., 2016). Because of this tendency, dual use represents an especially harmful practice (Chang et al., 2015; Lee et al., 2012). This observation has important implications for a large group of premium cigar users. For example, in PATH Wave 4, only about one-third (33.7 percent) of current premium cigar users were never-cigarette users; 25.7 and 40.6 percent were current or former cigarette users, respectively (Jeon and Mok, 2022). See Chapter 3 for more information on co-use of premium cigars.
When assessing the emissions of various chemicals from premium cigars, it is important to understand how consumers are using them in natural settings (real-life conditions). In principle, mouth-level exposure to toxicants from premium cigars can be measured in laboratory settings. Tobacco smoke could be generated from a machine that closely mimics the puffing behavior of a human smoker. Replicated human puffing measures can be used to drive machine smoking of premium cigars for post hoc analyses of mainstream smoke components. Many commercially available smoking machines can be fully programmable to closely replicate users’ behavior such that cigar smoke can be generated in a laboratory setting.
The practical consequence of the wide variations in smoking behavior among cigar users renders standardized machine smoking paradigms (e.g., ISO/FTC or CIR) potentially inappropriate for the replication of cigar smoke for analysis of mainstream smoke constituents (Koszowski et al., 2017). Cigar testing puffing conditions developed originally in 1973 by the industry-formed International Committee for Cigar Smoke Studies and currently recommended by CORESTA require that large cigars be smoked for analytical purposes using a puff volume of 20 mL (adjusted for large cigars with diameter above 12 mm to achieve a constant airflow through cigar of 11.8 cm/second), a puff duration of 1.5 seconds, and frequency of puffing every 40 seconds (CORESTA, 2018). Those standardized protocols with fixed puff volumes, constant interpuff interval, and constant velocity may not be reflective of actual human smoking.
As highlighted, a major factor that may influence cigar puffing behavior appears to be a concurrent use of other combustible tobacco products, particularly cigarettes. However, other factors could also potentially influence depth of inhalation. For example, product size, density of tobacco filler, moisture of the product, and tip cutting technique may all influence airflow through the product (Watson, 2021). Restricting airflow could result in puffing harder. An increase or decrease in the cigar smoke pH may also lead to more changes in the sensory experience (Henningfield et al., 1999). Smoke that is perceived as harsh may be difficult to inhale,
while smoke that is smooth and pleasant tasting could be easily inhaled. Finally, flavorings and sweeteners may also make cigar smoke more palatable; see the next section in this chapter for more information.
As discussed in Chapter 5, low intensity of puffing and restricted inhalation of smoke during use of premium cigars have important implications for health risks observed in these users. Some users may think of cigars as less harmful than cigarettes because of the difference in the amount smoked and the inhalation style, including perceived “no inhalation,” of cigar smoke (Majeed et al., 2018). Several studies have found that beliefs that cigar users do not inhale appear to drive perceptions of less risk compared to conventional cigarettes (Bascombe et al., 2016; Cornacchione et al., 2016; Jarman et al., 2017; Jolly, 2008; Nyman et al., 2016). When asked about health risks, most participants in those studies indicated that they believed that cigars are not as risky as cigarettes. See Chapter 4 for more information on perceived risk.
In summary, inhalation patterns and the resulting exposure to nicotine and harmful and potentially harmful smoke constituents have not been studied directly in premium cigar users. However, based on the measurement of inhalation patterns among users of large cigars and studies that examined the effect of inhalation patterns on exposure to nicotine and toxicants from conventional cigarettes (Burling et al., 1985; Clark et al., 1998; Gori et al., 1986; Ingebrethsen, 2006; Tobin et al., 1982), the available data strongly suggest that inhalation patterns will be important determinants of exposure in premium cigar users, too. In particular, studies that examined the effect of inhalation patterns on exposure to nicotine and toxicants from conventional cigarettes suggest the significant effect of the depth of smoke inhalation. Although data from experimental studies that objectively measured puffing patterns in large cigar users who also smoke conventional cigarettes (dual users) are limited, they are consistent with self-reported inhalation patterns of cigar smokers who used to smoke cigarettes. Taken together, findings from these studies suggest that, compared to those who only smoke cigars, dual users of cigars and cigarettes are more prone to smoking cigars with a greater intensity and therefore inhaling the smoke more deeply.
Conclusion 2-5: There is strongly suggestive evidence that the inhalation patterns of cigar smokers in general significantly affect their exposure to nicotine and harmful and potentially harmful constituents. At present, the extent to which premium cigar users who do not inhale have systemic exposure to nicotine and harmful and potentially harmful constituents remains unknown. It is likely that smokers of premium cigars who concurrently smoke cigarettes or smoked cigarettes in the past inhale more smoke compared to exclusive users of premium cigars.
As explained in Chapter 1 and earlier in this chapter, the committee’s definition of premium cigars excludes flavors. However, cigars otherwise matching the definition of premium used by the committee are sometimes flavored. Additionally, FDA and NIH asked the committee a research question about the potential effects of added flavors, which are an important consideration because they could influence the constituent profile and use of tobacco products like premium cigars.
Manufacturing of Flavored Cigars
Cigars vary by not only size but also added, characterizing flavors (Corey et al., 2014). Premium cigars can have leathery, earthy, spicy, nutty, or creamy notes, achieved by blending various strains of tobacco (Holt’s Clubhouse, 2020; Savona, 2005). Many premium cigar companies also offer flavored cigars, most commonly infused with coffee or liquor (Savona, 2005). These are directly flavored with syrups, liquors, and food products. They are handmade and steeped, soaked, or infused with flavors, such as vanilla, rum, or honey (Savona, 2005). Additionally, concept-named cigars (such as “tropical”) use nonspecific words that are not normally linked to specific flavors but still suggest appealing and palatable impressions.
Two common methods of adding flavors to cigars result in two types of products commonly referred to either as “flavored cigars” or “infused cigars” (Frontline Cigars, n.d.; Savona, 2005). Flavored cigars can be made by spraying a flavoring agent onto the tobacco or onto the rolled cigar or injecting a flavor solution inside a cigar. During the manufacturing of infused cigars, the absorbent tobacco or tobacco wrapper can simply sit in an area permeated by aromas, such as a room lined with botanicals, oils, and herbs (Maloney, n.d.).
Sensory Effects of Flavors Used in Cigars
The experience of flavor among tobacco users is a combination of olfactory, gustatory, and trigeminal effects. Flavors may influence expectancies (i.e., cognitive representations of likely effects) of tobacco products, and expectations of positive sensory effects of smoking (e.g., look, feel, and taste) are predictive of smoking behavior and willingness to try a product (Ashare et al., 2007; Harrell and Juliano, 2012; Hendricks and Brandon, 2005, 2008). Much of the literature on sensory effects of flavored tobacco focuses on cigarettes, given their greater prevalence, but is nonetheless instructive for examining other tobacco products. Sensory blockade reduces urge to smoke, providing indirect evidence for the
importance of sensory factors in maintaining behavior (Rose et al., 1985), and a body of work has attempted to dissociate the sensory and drug components of smoking (Rose, 2006; Rose et al., 1985, 1993, 2003; Westman et al., 1996).
Giovenco and colleagues (2017) conducted semistructured telephone interviews with 40 young adult U.S. cigar or cigarillo users to assess perceptions of product features and patterns of use. Most respondents smoked products with flavors infused in the tobacco and the cigarillo’s outer wrap. However, some preferred unflavored products because of the lack of chemical additives. Users were excited by the wide variety of flavors available and commonly reported trying many flavored varieties of their favorite brands. They also highlighted the enjoyable aroma of the smoke and a smoother and easier inhalation as benefits. Some former cigarette users reported that a flavored cigar was their first cigar experience and helped facilitate a shift to regular use.
Flavored little cigar and cigarillo use has been tied to smoking cannabis in a form of blunt9 (Delnevo et al., 2015; Giovenco et al., 2017). Sifaneck and colleagues (2005) found that flavors greatly influenced young peoples’ choice of cigars to use as blunts, as a flavored cigar wrapper can be used to mask cannabis odor or could help conceal cannabis smoking in public as a blunt in cigar form (Sifaneck et al., 2005). In the aforementioned study by Giovenco and colleagues (2017), many blunt users reported that flavors enhanced the taste of cannabis and made smoking more enjoyable, although some users disliked flavored cigars, particularly with high-quality cannabis.
See Box 2-1 for information about the regulatory implications of flavored cigars, Chapter 3 for more information on the popularity of flavored cigars, and Chapter 5 for discussion of the potential health effects of adding flavors to cigars.
Despite the many different types of cigars in the U.S. market, including premium cigars, all cigar tobaccos contain the highly addictive compound nicotine, as well as toxicants and carcinogenic tobacco-specific nitrosamines. During smoking of all types of cigars, these compounds are transferred to the smoker along with multiple combustion products, many of which are toxic or carcinogenic. While specific data on chemical composition of premium cigar smoke are minimal, it is probable that the mixture of carcinogens and toxicants is qualitatively similar to that of other cigar types. See Chapter 5 for additional information on the health
effects of these toxicants. The committee has added some new data on premium cigar characteristics, including weight and nicotine content, through commissioned work (see Appendix F).
Although it has been shown that the pH of tobacco products affects nicotine delivery, its effect on inhalation patterns and nicotine absorption in premium cigar users has not been studied systematically. Higher pH (more alkaline) of premium cigar smoke appears to facilitate nicotine absorption even in users who do not inhale. Data on premium cigar smoke inhalation topography are limited; however, past or concurrent users of other combustible tobacco products appear to puff more intensely on cigars compared to those users who only smoke cigars.
Methods are available for the analysis of premium cigar tobacco for hazardous and potentially hazardous compounds, but developing standardized conditions for quantitation of constituents of premium cigar smoke is a research priority; CORESTA may be well placed to develop these reproducible methods. Studies on puffing topography and systemic exposure to nicotine and toxicants from premium cigars also need to be prioritized. See Box 2-2 for more key research and measurement gaps.
Ashare, R. L., L. W. Hawk, Jr., K. M. Cummings, R. J. O’Connor, B. V. Fix, and W. C. Schmidt. 2007. Smoking expectancies for flavored and non-flavored cigarettes among college students. Addictive Behaviors 32(6):1252–1261.
Balbo, S., S. James-Yi, C. S. Johnson, G. O’Sullivan, I. Stepanov, M. Wang, D. Bandyopadhyay, F. Kassie, S. Carmella, P. Upadhyaya, and S. S. Hecht. 2013. (S)-N’-nitrosonornicotine, a constituent of smokeless tobacco, is a powerful oral cavity carcinogen in rats. Carcinogenesis 34:2178–2183.
Bascombe, T. M., K. N. Scott, D. Ballard, S. A. Smith, W. Thompson, and C. J. Berg. 2016. Primary healthcare provider knowledge, beliefs and clinic-based practices regarding alternative tobacco products and marijuana: A qualitative study. Health Education Research 31(3):375–383.
Blank, M. D., S. Disharoon, and T. Eissenberg. 2009. Comparison of methods for measurement of smoking behavior: Mouthpiece-based computerized devices versus direct observation. Nicotine & Tobacco Research 11(7):896–903.
Brunnemann, K. D., and D. Hoffmann. 1974. The pH of tobacco smoke. Food and Cosmetics Toxicology 12(1):115–124.
Burling, T. A., M. L. Stitzer, G. E. Bigelow, and A. M. Mead. 1985. Smoking topography and carbon monoxide levels in smokers. Addictive Behaviors 10(3):319–323.
Caruso, R. V., R. J. O’Connor, M. J. Travers, C. D. Delnevo, and W. E. Stephens. 2015. Design characteristics and tobacco metal concentrations in filtered cigars. Nicotine & Tobacco Research 17(11):1331–1336.
CDC (Centers for Disease Control and Prevention). 2012. Consumption of cigarettes and combustible tobacco—United States, 2000–2011. Morbidity and Mortality Weekly Report 61(30):565–569.
Cecil, T. L., T. M. Brewer, M. Young, and M. R. Holman. 2017. Acrolein yields in mainstream smoke from commercial cigarette and little cigar tobacco products. Nicotine & Tobacco Research 19(7):865–870.
Chang, C. M., C. G. Corey, B. L. Rostron, and B. J. Apelberg. 2015. Systematic review of cigar smoking and all cause and smoking related mortality. BMC Public Health 15:390.
Chang, C. M., B. L. Rostron, J. T. Chang, C. G. Corey, H. L. Kimmel, C. S. Sosnoff, M. L. Goniewicz, K. C. Edwards, D. K. Hatsukami, Y. Wang, A. Y. Del Valle-Pinero, M. Yang, M. J. Travers, S. Arnstein, K. Taylor, K. Conway, B. K. Ambrose, N. Borek, A. Hyland, L. Wang, B. C. Blount, and D. M. van Bemmel. 2019. Biomarkers of exposure among U.S. adult cigar smokers: Population Assessment of Tobacco and Health (PATH) study Wave 1 (2013–2014). Cancer Epidemiology, Biomarkers & Prevention 28(5):943–953.
Chen, J., A. Kettermann, B. L. Rostron, and H. R. Day. 2014. Biomarkers of exposure among U.S. cigar smokers: An analysis of 1999–2012 National Health and Nutrition Examination Survey (NHANES) data. Cancer Epidemiology, Biomarkers & Prevention 23(12):2906–2915.
Chowdhury, A., and N. Gill. 2021. Will FDA extend its proposed ban on menthol cigarettes and characterizing flavors in cigars to flavored ENDS products? https://www.fdli.org/2021/08/will-fda-extend-its-proposed-ban-on-menthol-cigarettes-and-characterizing-flavors-in-cigars-to-flavored-ends-products/ (accessed November 10, 2021).
Cigar Aficionado. n.d. Homogenized tobacco leaf. https://www.cigaraficionado.com/glossary/homogenized-tobacco-leaf (accessed January 5, 2022).
Clark, K. D., N. Wardrobe-Wong, J. J. Elliott, P. T. Gill, N. P. Tait, and P. D. Snashall. 1998. Cigarette smoke inhalation and lung damage in smoking volunteers. European Respiratory Journal 12(2):395–399.
Claus, E. D., B. C. Moeller, D. Harbour, P. J. Kuehl, M. McGuire, J. C. Vivar, and M. J. Schroeder. 2018. Use behaviors, dependence, and nicotine exposure associated with ad libitum cigar smoking. Tobacco Regulatory Science 4(1):548–561.
CORESTA (Cooperation Centre for Scientific Research Relative to Tobacco). 2018. CORESTA recommended method no. 64: Routine analytical cigar-smoking machine specifications, definitions and standard conditions. Paris, France: Cooperation Centre for Scientific Research Relative to Tobacco.
CORESTA. 2020. CORESTA recommended method no. 62: Determination of nicotine in tobacco and tobacco products by gas chromatographic analysis. Paris, France: Cooperation Centre for Scientific Research Relative to Tobacco.
CORESTA. 2021. Cigar smoking methods sub-group technical report: Collaborative study on handmade cigar smoke anlaysis (TPM, water, nicotine, NFDPM, CO and puff count). Paris, France: Cooperation Centre for Scientific Research Relative to Tobacco.
Corey, C. G., B. A. King, B. N. Coleman, C. D. Delnevo, C. G. Husten, B. K. Ambrose, and B. J. Apelberg. 2014. Little filtered cigar, cigarillo, and premium cigar smoking among adults—United States, 2012–2013. Morbidity and Mortality Weekly Report 63(30):650–654.
Corey, C. G., E. Holder-Hayes, A. B. Nguyen, C. D. Delnevo, B. L. Rostron, M. Bansal-Travers, H. L. Kimmel, A. Koblitz, E. Lambert, J. L. Pearson, E. Sharma, C. Tworek, A. J. Hyland, K. P. Conway, B. K. Ambrose, and N. Borek. 2018. U.S. adult cigar smoking patterns, purchasing behaviors, and reasons for use according to cigar type: Findings from the Population Assessment of Tobacco and Health (PATH) study, 2013–2014. Nicotine & Tobacco Research 20(12):1457–1466.
Cornacchione, J., K. G. Wagoner, K. D. Wiseman, D. Kelley, S. M. Noar, M. H. Smith, and E. L. Sutfin. 2016. Adolescent and young adult perceptions of hookah and little cigars/cigarillos: Implications for risk messages. Journal of Health Communication 21(7):818–825.
Delnevo, C. D., and M. Hrywna. 2007. “A whole ’nother smoke” or a cigarette in disguise: How RJ Reynolds reframed the image of little cigars. American Journal of Public Health 97(8):1368–1375.
Delnevo, C. D., and M. Hrywna. 2015. Clove cigar sales following the U.S. flavoured cigarette ban. Tobacco Control 24(e4):e246–e250.
Delnevo, C. D., D. P. Giovenco, B. K. Ambrose, C. G. Corey, and K. P. Conway. 2015. Preference for flavoured cigar brands among youth, young adults and adults in the USA. Tobacco Control 24(4):389–394.
Delnevo, C. D., D. P. Giovenco, and E. J. Miller Lo. 2017a. Changes in the mass-merchandise cigar market since the Tobacco Control Act. Tobacco Regulatory Science 3(2 Suppl 1):S8–S16.
Delnevo, C. D., M. Hrywna, D. P. Giovenco, E. J. Miller Lo, and R. J. O’Connor. 2017b. Close, but no cigar: Certain cigars are pseudo-cigarettes designed to evade regulation. Tobacco Control 26(3):349–354.
Delnevo, C. D., E. Miller Lo, D. P. Giovenco, J. Cornacchione Ross, M. Hrywna, and A. A. Strasser. 2021. Cigar sales in convenience stores in the U.S., 2009–2020. JAMA 326(23):2429–2431.
Dethloff, O., C. Mueller, X. Cahours, and S. Colard. 2017. Cigar burning under different smoking intensities and effects on emissions. Regulatory Toxicology and Pharmacology 91:190–196.
Ding, Y. S., L. Zhang, R. B. Jain, N. Jain, R. Y. Wang, D. L. Ashley, and C. H. Watson. 2008. Levels of tobacco-specific nitrosamines and polycyclic aromatic hydrocarbons in mainstream smoke from different tobacco varieties. Cancer Epidemiology, Biomarkers & Prevention 17(12):3366–3371.
Doll, R., and R. Peto. 1976. Mortality in relation to smoking: 20 years’ observations on male British doctors. BMJ 2(6051):1525–1536.
Edwards, S. H., M. D. Hassink, K. M. Taylor, C. H. Watson, P. Kuklenyik, B. Kimbrell, L. Wang, P. Chen, and L. Valentín-Blasini. 2021. Tobacco-specific nitrosamines in the tobacco and mainstream smoke of commercial little cigars. Chemical Research in Toxicology 34(4):1034–1045.
Erythropel, H. C., G. Kong, T. M. deWinter, S. S. O’Malley, S. E. Jordt, P. T. Anastas, and J. B. Zimmerman. 2018. Presence of high-intensity sweeteners in popular cigarillos of varying flavor profiles. JAMA 320(13):1380–1383.
FDA (Food and Drug Administration). 2016. Deeming tobacco products to be subject to the federal Food, Drug, and Cosmetic Act, as amended by the Family Smoking Prevention and Tobacco Control Act; restrictions on the sale and distribution of tobacco products and required warning statements for tobacco products. Final rule. Federal Register 81(90):28973–29106.
FDA. 2020. Family Smoking Prevention and Tobacco Control Act: An overview. https://www.fda.gov/tobacco-products/rules-regulations-and-guidance/family-smoking-prevention-and-tobacco-control-act-overview (accessed November 10, 2021).
Fresquez, M. R., N. Gonzalez-Jimenez, N. Gray, C. H. Watson, and R. S. Pappas. 2015. High-throughput determination of mercury in tobacco and mainstream smoke from little cigars. Journal of Analytical Toxicology 39(7):545–550.
Frontline Cigars. n.d. How are flavored cigars different from other cigars? https://www.frontlinecigars.com/pages/how-are-flavored-cigars-different-from-other-cigars (accessed October 20, 2021).
Gammon, D. G., T. Rogers, E. M. Coats, J. M. Nonnemaker, K. L. Marynak, N. M. Kuiper, and B. A. King. 2019. National and state patterns of concept-flavoured cigar sales, USA, 2012–2016. Tobacco Control 28(4):394–400.
Giovenco, D. P., E. J. Miller Lo, M. J. Lewis, and C. D. Delnevo. 2017. “They’re pretty much made for blunts”: Product features that facilitate marijuana use among young adult cigarillo users in the United States. Nicotine & Tobacco Research 19(11):1359–1364.
Goel, R., N. Trushin, S. M. Reilly, Z. Bitzer, J. Muscat, J. Foulds, and J. P. Richie, Jr. 2018. A survey of nicotine yields in small cigar smoke: Influence of cigar design and smoking regimens. Nicotine & Tobacco Research 20(10):1250–1257.
Gori, G. B., N. L. Benowitz, and C. J. Lynch. 1986. Mouth versus deep airways absorption of nicotine in cigarette smokers. Pharmacology Biochemistry and Behavior 25(6):1181–1184.
Hamad, S. H., N. M. Johnson, M. E. Tefft, M. C. Brinkman, S. M. Gordon, P. I. Clark, and S. S. Buehler. 2017. Little cigars vs. 3R4F cigarette: Physical properties and HPHC yields. Tobacco Regulatory Science 3(4):459–478.
Harrell, P. T., and L. M. Juliano. 2012. A direct test of the influence of nicotine response expectancies on the subjective and cognitive effects of smoking. Experimental and Clinical Psychopharmacology 20(4):278–286.
Hecht, S. S., A. Rivenson, J. Braley, J. DiBello, J. D. Adams, and D. Hoffmann. 1986. Induction of oral cavity tumors in F344 rats by tobacco-specific nitrosamines and snuff. Cancer Research 46(8):4162–4166.
Hendricks, P. S., and T. H. Brandon. 2005. Smoking expectancy associates among college smokers. Addictive Behaviors 30(2):235–245.
Hendricks, P. S., and T. H. Brandon. 2008. Smokers’ expectancies for smoking versus nicotine. Psychology of Addictive Behaviors 22(1):135–140.
Henningfield, J. E., R. V. Fant, A. Radzius, and S. Frost. 1999. Nicotine concentration, smoke pH and whole tobacco aqueous pH of some cigar brands and types popular in the United States. Nicotine & Tobacco Research 1(2):163–168.
Holt’s Clubhouse. 2020. Cigar 101: Most popular cigar tasting notes and flavors. https://www.holts.com/clubhouse/cigar-101/most-common-cigar-flavors-tasting-notes (accessed November 10, 2021).
IARC (International Agency for Research on Cancer). 2004. Volume 83: Tobacco smoke and involuntary smoking. Lyon, France: International Agency for Research on Cancer.
IARC. 2007. Volume 89: Smokeless tobacco and some tobacco-specific N-nitrosamines. Lyon, France: International Agency for Research on Cancer.
Ingebrethsen, B. J. 2006. Numerical simulation of the effects of dilution level, depth of inhalation, and smoke composition on nicotine vapor deposition during cigarette smoking. Inhalation Toxicology 18(14):1071–1076.
ISO (International Organization for Standardization). 2012. ISO 3308:2012 routine analytical cigarette-smoking machine—definitions and standard conditions. Geneva, Switzerland: International Organization for Standardization.
Jablonski, J. J., J. H. Maines, A. G. Cheetham, and I. G. Gillman. 2019. Comparative levels of carbonyl delivery between mass-market cigars and cigarettes. Regulatory Toxicology and Pharmacology 108:104453.
Jacob, P., 3rd, L. Yu, A. T. Shulgin, and N. L. Benowitz. 1999. Minor tobacco alkaloids as biomarkers for tobacco use: Comparison of users of cigarettes, smokeless tobacco, cigars, and pipes. American Journal of Public Health 89(5):731–736.
Jarman, K. L., S. D. Kowitt, J. C. Ross, A. O. Goldstein, and A. O. Goldstein. 2017. Are some of the cigar warnings mandated in the U.S. more believable than others? International Journal of Environmental Research and Public Health 14(11):1370.
Jeon, J., and Y. Mok. 2022. Cross-sectional patterns and longitudinal transitions of cigar use by type in the PATH study. Paper commissioned by the Committee on Patterns of Use and Health Effects of “Premium Cigars” and Priority Research (Appendix D).
Jolly, D. H. 2008. Exploring the use of little cigars by students at a historically Black university. Preventing Chronic Disease 5(3):A82.
Klupinski, T. P., E. D. Strozier, D. A. Friedenberg, M. C. Brinkman, S. M. Gordon, and P. I. Clark. 2016. Identification of new and distinctive exposures from little cigars. Chemical Research in Toxicology 29(2):162–168.
Koszowski, B. 2021. Nicotine pharmacokinetics and puffing behaviors of large cigar smokers. Presentation to the Committee on Patterns of Use and Health Effects of “Premium Cigars” and Priority Research. May 28, 2021. https://www.nationalacademies.org/event/05-28-2021/health-effects-and-patterns-of-use-of-premium-cigars-meeting-3-part-1 (accessed March 30, 2022).
Koszowski, B., Z. R. Rosenberry, A. Kanu, L. C. Viray, J. L. Potts, and W. B. Pickworth. 2015. Nicotine and carbon monoxide exposure from inhalation of cigarillo smoke. Pharmacology Biochemistry and Behavior 139(Pt A):7–14.
Koszowski, B., Z. R. Rosenberry, D. Yi, S. Stewart, and W. B. Pickworth. 2017. Smoking behavior and smoke constituents from cigarillos and little cigars. Tobacco Regulatory Science 3(Suppl 1):S31–S40.
Koszowski, B., M. H. Thanner, W. B. Pickworth, K. M. Taylor, L. C. Hull, and M. J. Schroeder. 2018. Nicotine content and physical properties of large cigars and cigarillos in the United States. Nicotine & Tobacco Research 20(3):393–398.
Lawler, T. S., S. B. Stanfill, B. R. deCastro, J. G. Lisko, B. W. Duncan, P. Richter, and C. H. Watson. 2017. Surveillance of nicotine and pH in cigarette and cigar filler. Tobacco Regulatory Science 3(Suppl 1):101–116.
Lawyer, G. R., M. Jackson, M. Prinz, T. Lamb, Q. Wang, T. Muthumalage, and I. Rahman. 2019. Classification of flavors in cigarillos and little cigars and their variable cellular and acellular oxidative and cytotoxic responses. PLoS One 14(12):e0226066.
Lee, E. M., J. L. Malson, A. J. Waters, E. T. Moolchan, and W. B. Pickworth. 2003. Smoking topography: Reliability and validity in dependent smokers. Nicotine & Tobacco Research 5(5):673–679.
Lee, P. N., B. A. Forey, and K. J. Coombs. 2012. Systematic review with meta-analysis of the epidemiological evidence in the 1900s relating smoking to lung cancer. BMC Cancer 12:385.
Lindegaard, T. 2021. Introduction to CORESTA work related to premium cigars. Presentation to the Committee on Patterns of Use and Health Effects of “Premium Cigars” and Priority Research. April 23, 2021. https://www.nationalacademies.org/event/04-20-2021/docs/DFC0F1D56EA4AC988BF87F64A8DE10EB7DCA8A9FC6CF (accessed November 12, 2021).
Liu, W.-H., G.-P. Yong, L. Fang, S.-K. Wang, H.-J. Bai, J.-H. Jiang, and S.-M. Liu. 2008. Free and conjugated phytosterols in cured tobacco leaves: Influence of genotype, growing region, and stalk position. Journal of Agricultural and Food Chemistry 56(1):185–189.
Long, J. 2021. California is second state to prohibit flavored tobacco product sales. https://www.publichealthlawcenter.org/blogs/2020-08-28/california-second-state-prohibit-flavored-tobacco-product-sales (accessed October 25, 2021).
Majeed, B. A., A. Nyman, K. L. Sterling, and P. Slovic. 2018. Little cigars and cigarillos: Affect and perceived relative harm among U.S. adults, 2015. Addictive Behaviors 85:107–112.
Maloney, T. L. n.d. Infused and flavored cigars. http://otlgolf.com/infused-and-flavored-cigars (accessed November 11, 2021).
McDonald, L. J., R. S. Bhatia, and P. D. Hollett. 2002. Deposition of cigar smoke particles in the lung: Evaluation with ventilation scan using 99mTc-labeled sulfur colloid particles. The Journal of Nuclear Medicine 43(12):1591–1595.
Minister of Justice. 2019. Tobacco reporting regulations sor/2000-273. Ottawa, Canada: Minister of Justice, Government of Canada.
NCI (National Cancer Institute). 1985. Selection, follow-up, and analysis in prospective studies: A workshop. National Cancer Institute monograph no. 67. NIH pub. No. 85-2713. Bethesda, MD: National Cancer Institute.
NCI. 1998. Cigars: Health effects and trends. Tobacco control monograph no. 9. NIH pub. No. 98-4302. Bethesda, MD: National Cancer Institute.
Ng, L. K., M. Hupé, M. Vanier, and D. Moccia. 2001. Characterization of cigar tobaccos by gas chromatographic/mass spectrometric analysis of nonvolatile organic acids: Application to the authentication of Cuban cigars. Journal of Agricultural and Food Chemistry 49(3):1132–1138.
Nyman, A. L., K. L. Sterling, S. R. Weaver, B. A. Majeed, and M. P. Eriksen. 2016. Little cigars and cigarillos: Users, perceptions, and reasons for use. Tobacco Regulatory Science 2(3):239–251.
Pappas, R. S., N. Martone, N. Gonzalez-Jimenez, M. R. Fresquez, and C. H. Watson. 2015. Determination of toxic metals in little cigar tobacco with “triple quad” ICP-MS. Journal of Analytical Toxicology 39(5):347–352.
Philip Morris International. n.d. Tobacco farming and curing. https://www.pmi.com/who-we-are/tobacco-facts/tobacco-farming-and-curing (accessed November 10, 2021).
Pickworth, W. B., Z. R. Rosenberry, and B. Koszowski. 2017a. Toxicant exposure from smoking a little cigar: Further support for product regulation. Tobacco Control 26(3):269–276.
Pickworth, W. B., Z. R. Rosenberry, K. E. O’Grady, and B. Koszowski. 2017b. Dual use of cigarettes, little cigars, cigarillos, and large cigars: Smoking topography and toxicant exposure. Tobacco Regulatory Science 3(Suppl 1):S72–S83.
Pickworth, W. B., Z. R. Rosenberry, D. Yi, E. N. Pitts, W. Lord-Adem, and B. Koszowski. 2018. Cigarillo and little cigar mainstream smoke constituents from replicated human smoking. Chemical Research in Toxicology 31(4):251–258.
Reilly, S. M., R. Goel, Z. Bitzer, R. J. Elias, J. Foulds, J. Muscat, and J. P. Richie. 2018. Little cigars, filtered cigars, and their carbonyl delivery relative to cigarettes. Nicotine & Tobacco Research 20:S969–S106.
Rogers, T., A. Feld, D. G. Gammon, E. M. Coats, E. M. Brown, L. T. Olson, J. M. Nonnemaker, M. Engstrom, T. McCrae, E. Holder-Hayes, A. Ross, E. Boles Welsh, G. Guardino, and D. N. Pearlman. 2020. Changes in cigar sales following implementation of a local policy restricting sales of flavoured non-cigarette tobacco products. Tobacco Control 29(4):412–419.
Rose, J. E. 2006. Nicotine and nonnicotine factors in cigarette addiction. Psychopharmacology (Berl) 184(3-4):274–285.
Rose, J. E., F. M. Behm, and E. D. Levin. 1993. Role of nicotine dose and sensory cues in the regulation of smoke intake. Pharmacology Biochemistry and Behavior 44(4):891–900.
Rose, J. E., F. M. Behm, E. C. Westman, J. E. Bates, and A. Salley. 2003. Pharmacologic and sensorimotor components of satiation in cigarette smoking. Pharmacology Biochemistry and Behavior 76(2):243–250.
Rose, J. E., D. P. Tashkin, A. Ertle, M. C. Zinser, and R. Lafer. 1985. Sensory blockade of smoking satisfaction. Pharmacology Biochemistry and Behavior 23(2):289–293.
Rosenberry, Z. R., W. B. Pickworth, and B. Koszowski. 2018. Large cigars: Smoking topography and toxicant exposure. Nicotine & Tobacco Research 20(2):183–191.
Rostron, B. L., M. J. Schroeder, and B. K. Ambrose. 2016. Dependence symptoms and cessation intentions among U.S. adult daily cigarette, cigar, and e-cigarette users, 2012–2013. BMC Public Health 16(1):814.
Rostron, B. L., C. G. Corey, E. Holder-Hayes, and B. K. Ambrose. 2019. Estimating the potential public health impact of prohibiting characterizing flavors in cigars throughout the U.S. International Journal of Environmental Research and Public Health 16(18):3234.
Savona, D. 2005. Cigars of a different flavor. Cigar Aficionado Magazine. https://www.cigaraficionado.com/article/cigars-of-a-different-flavor-8595 (accessed November 11, 2021).
Sifaneck, S. J., B. D. Johnson, and E. Dunlap. 2005. Cigars-for-blunts: Choice of tobacco products by blunt smokers. Journal of Ethnicity in Substance Abuse 4(3–4):23–42.
Tobin, M. J., G. Jenouri, and M. A. Sackner. 1982. Subjective and objective measurement of cigarette smoke inhalation. Chest 82(6):696–700.
Tomar, S. L., and J. E. Henningfield. 1997. Review of the evidence that pH is a determinant of nicotine dosage from oral use of smokeless tobacco. Tobacco Control 6(3):219–225.
TTB (Alcohol and Tobacco Tax and Trade Bureau). 2017. Federal excise tax increase and related provisions. https://www.ttb.gov/main-pages/federal-excise-tax-inrease-and-related-provisions (accessed November 10, 2021).
Vonder Haar, M. 2021. Tobacco and nicotine trends to watch. https://www.cspdailynews.com/tobacco/tobacco-nicotine-trends-watch (accessed October 26, 2021).
Vu, A. T., M. D. Hassink, K. M. Taylor, M. McGuigan, A. Blasiole, L. Valentin-Blasini, K. Williams, and C. H. Watson. 2021. Volatile organic compounds in mainstream smoke of sixty domestic little cigar products. Chemical Research in Toxicology 34(3):704–712.
Watson, C. H. 2021. Harmonizing machine testing measurement on premium cigar mainstream smoke. Presentation to the Committee on Patterns of Use and Health Effects of “Premium Cigars” and Priority Research. May 28, 2021. https://www.nationalacademies.org/event/05-28-2021/health-effects-and-patterns-of-use-of-premium-cigars-meeting-3-part-1 (accessed March 30, 2022).
Westman, E. C., F. M. Behm, and J. E. Rose. 1996. Dissociating the nicotine and airway sensory effects of smoking. Pharmacology Biochemistry and Behavior 53(2):309–315.
Yassin, S., J. Giberson, and M. Page. 2021. Cigar physical characteristics. Paper Commissioned by the Committee on Patterns of Use and Health Effects of “Premium Cigars” and Priority Research (Appendix F).