Volume 31 (2022): Issue 3 (November 2022)

A novel concept is described here that utilizes externally applied heat to a solid rod of reconstituted tobacco biomass to form a stream of aerosol under progressively oxygen-deficient atmosphere. The boundary of auto-ignition was determined at oxygen concentrations of 0%, 5%, 10%, and 21% and then the effects of these different atmospheres on various parameters were studied. Experimental results indicated that the ignition temperature decreased with the increase of oxygen concentration and a negative temperature coefficient (NTC) for atmosphere with oxygen was observed at before but close to ignition temperature. Significant differences in the yields of CO and CO₂ between oxygen and oxygen-free atmosphere were observed. The mass of aerosol produced under an inert atmosphere and reduced-oxygen atmosphere were characterized with selected volatile and semi-volatile components, phenols, aldehydes, and other organic compounds of interests. In addition, higher oxygen concentration resulted in higher bulk and surface oxygen content of solid-phase residue, the reduction of carbon and hydrogen element content and related functional groups, and the content of inorganic compounds also exhibited an increase with oxygen concentration. By systematically changing oxygen concentrations of the biomass bed with increasing temperatures, an aerosol stream of controlled chemical composition and yields could be formed without leading to ignition. Key chemical markers of inhalation harm were measured and compared to each other under different degrees close to combustion. Studying reconstituted tobacco or other biomass materials in such a way could provide alternative and useful information in the design heated biomass aerosol generators.

For tobacco strips used in cigarette production, the stem content is an important quality index to assess the impurity level of the cut leaves. The presented work developed a nondestructive detection method of stems in cut leaf agricultural products by the low energy X-ray imaging. The algorithm of stem image processing and weight calculation principle was established, and then a machine vision system with X-ray imaging and image analysis was set up to verify the quantitative detection method. The results showed that the relative error of the detection method ranged from −3.64% to 2.76%. The determination of stems with a different morphology, such as the thick stem, were also realized based on the image analysis. The accuracy of determining thick stem and long stem was 94.67% and 99.33%, respectively. The developed method is superior to the current ISO detection method of tobacco stem in leaves under the same testing conditions in terms of accuracy and efficiency, which could be applied as an effective online detection method to monitor the quality of processed leaf for cigarette production.

Biodegradation is the process by which organic substances are broken down into carbon dioxide (CO₂) and water (H₂O) by living microbial organisms. With the advancement in analytical techniques, standard methods have been developed and published by the International Organization for Standardization (ISO), eliminating the ambiguity associated with biodegradation testing for several materials. There is no data available on biodegradation of cigarette filters that follows a standardized and validated ISO method.

The objective of this study is to understand the biodegradation of conventional and non-conventional cellulose acetate (CA) Cigarette Filters, Infused Paper Filter (IP), and Combined Material Filter (CMF), Condensed Tobacco End Filter (CTEC) and bidi butts. In this study, cigarettes and bidis were smoked on a smoking machine following the standard ISO 3308 for cigarettes and the standard ISO 17175 for bidis. After smoking, cigarette filters and bidi butts were subjected to biodegradation testing, adopting the standard ISO 14855-1.

The study demonstrated 92.1% biodegradation in 151 days for cellulose acetate cigarette filters, 91.9% biodegradation in 97 days for DE-Tow^TM (Cellulose acetate with additives) filters, 96.2% biodegradation in 86 days for CMF, 93.4% biodegradation in 55 days for paper filters, 92.1% biodegradation in 54 days for bidi butts, and 95.3% biodegradation in 37 days for CTEC filters were recorded. This study provided an unbiased proof that the cigarette filters made of cellulose acetate are biodegradable as per the standard ISO 14855-1. Also, Gel Permeation Chromatography (GPC) analysis was carried out on the smoked cigarette filters of Cellulose acetate, DE-Tow^TM and CMF as well as their resulting compost to detect any cellulose acetate remaining in the final compost. The GPC analysis indicated cellulose acetate peaks in smoked cigarette filters of cellulose acetate, DE-Tow^TM and CMF samples, whereas no cellulose acetate peak was observed in resulting compost samples. Hence it is concluded that cellulose acetate is not present in any of the resulting composts of cellulose acetate filters, DE-Tow^TM filters and CMF samples.

It is inferred from the results that cigarette filters and bidi butts chosen for the study have achieved the criteria of more than 90% biodegradation, which is well within the specified criteria of 180 days.

This article will be beneficial for entire scientific community, regulators as well as manufacturers in understanding the biodegradability of cigarette filters.

A lit cigarette forms a positive and negative pressure zone by a puff with respect to the position of its paper burn line. Smoke aerosols generated from the two zones are then pulled through the rod under the puff to form the mainstream smoke. This phenomenon is fundamental to the thermophysics and the resultant chemical composition of the mainstream smoke. In this study, we created two different airflow pathways inside a heated tobacco rod by a puff, and investigated the differences in aerosol formation and its chemical compositions. The two different pressure-induced conditions, one through an open-ended tobacco rod (marked as HNB, a label of a designed airflow pathway of commercial heated tobacco products called heat-not-burn prior), and the other through a closed-ended tobacco rod (marked as NSC, a label of a novel-designed airflow pathway of heated tobacco products), were compared for their aerosol collected mass (ACM), the contents of nicotine, water and added aerosol agents such as propylene glycol (PG) and glycerol (VG), as well as selected aldehydes and ketones in the mainstream aerosol. Aerosol particle distribution and the heated temperature along different rod locations were also compared during a puff. The results indicated marked differences in the aerosol formation processes between the two HNB and NSC systems. The transfer ratios of the main aerosol components were significantly higher for the NSC; the levels of formaldehyde and acetaldehyde were significantly lower under the NSC than the HNB condition. There were also significant differences for the aerosol particle number concentration (APNC) and count median diameter (CMD) for the two systems. The lack of convective heat transfer in the aerosol formation under the NSC condition resulted in a relatively stable thermal aerosol generation zone, reflected by the temperature difference between the two systems in the selected locations. The NSC mode of tobacco heating thus offers a novel and enhanced aerosol generation for heat tobacco product designs.

During the last 35 years technologies and hardware for the separation of enantiomers have advanced tremendously. Today, complete resolution of the enantiomers of nicotine and related compounds can effectively be attained within a few seconds and most often less than 10 minutes. In some unique cases, enantiomeric separation for nicotine-related compounds having a wide variety of functional groups has been demonstrated. Particularly, the successful wedding of short HPLC and SFC columns containing very small particle size materials bonded to chiral stationary phase materials coupled with information-rich detectors like electrospray ionization mass spectrometry/mass spectrometry has facilitated this remarkable transition. Taken collectively the HPLC and SFC technologies will allow for very rapid (seconds), reliable, and reproducible (% RSD routinely < 5%) for nicotine and related alkaloid enantiomers.