Methodological Approaches for Risk Assessment of Tobacco and Related Products

Emissions from conventional and electronic waterpipes relative to cigarettes and a heated tobacco product

Harms associated with the use of smoked tobacco products, including waterpipes, are due to inhalational exposure to toxicants either present in tobacco or formed during the process of combustion. We assessed levels of 37 toxicants in aerosol emissions from conventional waterpipe heated with different charcoals and also with a heat management device (HMD), from the IQOS heated tobacco product (HTP), and the 'OOKA' electronic waterpipe. We also utilised literature data on toxicant yields in 3R4F reference cigarette smoke. When taking use patterns into account, toxicant yields were substantially lower in conventional waterpipe aerosol compared with cigarette smoke. Toxicant yields in electronic waterpipe aerosol were substantially lower than those in conventional waterpipe aerosol, both on a per session basis and when taking typical use patterns into account. Numerous toxicants in conventional waterpipe aerosol were absent in electronic waterpipe aerosol. In summary, during typical use conventional waterpipe emits fewer, and lower levels of, a number of toxicants relative to combustible cigarette smoke. In addition, electronically heating shisha further reduces toxicant levels, and many toxicants are absent in OOKA electronic waterpipe aerosol. These findings have important implications concerning toxicant exposure among waterpipe users, and for understanding how to potentially reduce health risks associated with waterpipe use.

Novel DNA methylation changes in mouse lungs associated with chronic smoking

Smoking is a potent cause of asthma exacerbations, chronic obstructive pulmonary disease (COPD) and many other health defects, and changes in DNA methylation (DNAm) have been identified as a potential link between smoking and these health outcomes. However, most studies of smoking and DNAm have been done using blood and other easily accessible tissues in humans, while evidence from more directly affected tissues such as the lungs is lacking. Here, we identified DNAm patterns in the lungs that are altered by smoking. We used an established mouse model to measure the effects of chronic smoke exposure first on lung phenotype immediately after smoking and then after a period of smoking cessation. Next, we determined whether our mouse model recapitulates previous DNAm patterns observed in smoking humans, specifically measuring DNAm at a candidate gene responsive to cigarette smoke, Cyp1a1. Finally, we carried out epigenome-wide DNAm analyses using the newly released Illumina mouse methylation microarrays. Our results recapitulate some of the phenotypes and DNAm patterns observed in human studies but reveal 32 differentially methylated genes specific to the lungs which have not been previously associated with smoking. The affected genes are associated with nicotine dependency, tumorigenesis and metastasis, immune cell dysfunction, lung function decline, and COPD. This research emphasizes the need to study CS-mediated DNAm signatures in directly affected tissues like the lungs, to fully understand mechanisms underlying CS-mediated health outcomes.

Rauchen – Wissenswertes über Tabak und alternative Produkte

Tabakrauchen ist weltweit die häufigste vermeidbare Ursache für Krankheit und vorzeitigen Tod. Rauchen ist keine Life-Style-Entscheidung oder nur eine (schlechte) Angewohnheit. Es ist eine chronische Krankheit, die viele Erkrankungen mitverursacht und aggraviert. Durch das psychoaktive Nikotin ist Rauchen zusätzlich eine Suchterkrankung. Bei der Strategie zur Harm Reduction sollen Raucher die Tabakzigarette durch alternative nikotinhaltige Produkte („Alternative Nicotine Delivery Products“), wie die E-Zigarette oder Tabakerhitzer (Heat-not-burn-Produkte), ersetzen. Tabakkonzerne bewerben im Rahmen ihrer Marketingstrategie diese Produkte mit einer Schadstoffreduktion um 95%. Jedoch stehen unabhängige Forschungen und Langzeitergebnisse diesbezüglich aus. Raucher, die zu derartigen Produkten wechseln, sind durch die fortbestehende Nikotinabhängigkeit weiterhin langfristig den Belastungen durch (kardio)toxische und karzinogene Substanzen ausgesetzt. Die gesundheitlichen Auswirkungen dieser inhalativen Noxen werden dargestellt, wobei die Heat-not-burn-Produkte eine Mittelstellung zwischen der schädlichsten Tabakzigarette und den (möglicherweise) weniger gesundheitsschädlichen E-Zigaretten einnehmen. Das Fortbestehen einer (wenn auch reduzierten) kontinuierlichen Exposition in Verbindung mit einer Nikotinabhängigkeit ist keine Alternative zu einer professionellen evidenzbasierten multimodalen Tabakentwöhnung, die endlich flächendeckend (auch in Deutschland) angeboten werden muss. Ziel sollte der komplette Verzicht auf inhalative Noxen sein, ohne jegliche Toleranz für die Marketingstrategien der Tabakkonzerne.

Advantages and Disadvantages of Electronic Cigarettes

Despite nearly nine thousand publications on e-cigarettes (EC) in the PubMed database, there is still no consensus in the scientific community and among decision makers regarding the risks and benefits of using these products [...].