O impacto dos aditivos do tabaco na toxicidade da fumaça do cigarro: uma avaliação crítica dos estudos patrocinados pela indústria do fumo / El impacto de los aditivos del tabaco en la toxicidad del humo del cigarrillo: una evaluación crítica de los estudios de la industria del tabaco / The impact of tobacco additives on cigarette smoke toxicity: a critical appraisal of tobacco industry studies

Resumo: A produção de cigarros envolve uma série de substâncias e materiais além do próprio tabaco, do papel e do filtro. Os aditivos do tabaco incluem conservantes, flavorizantes, intensificadores, umectantes, açúcares e compostos de amônio. Embora as empresas produtoras de tabaco aleguem que os aditivos não aumentam a toxicidade da fumaça e não tornam os cigarros mais atraentes ou viciantes, tais alegações são contestadas por pesquisadores independentes. Os autores realizaram uma revisão dos estudos sobre os efeitos dos aditivos sobre a composição química e toxicidade da fumaça. Os aditivos elevam os níveis de formaldeído e causam pequenas alterações nos níveis de outros analitos medidos na fumaça. Estudos toxicológicos (testes de mutagenicidade e de citotoxicidade em células de mamíferos, estudos da exposição por 90 dias por via inalatória em ratos e ensaios do micronúcleo em células da medula óssea) indicaram que os aditivos do tabaco não aumentam a toxicidade da fumaça. Entretanto, é conhecido que os estudos em roedores falham em predizer o potencial carcinogênico da fumaça do cigarro, e os testes realizados tiveram poder estatístico insuficiente para detectar diferenças pequenas, porém relevantes do ponto de vista toxicológico, entre cigarros experimentais (com aditivos) e controles (sem aditivos). Em conclusão, esta revisão da literatura mostrou que o impacto dos aditivos na toxicidade da fumaça do tabaco ainda permanece por ser esclarecido.

Resumen: La producción de cigarrillos involucra un número de sustancias y materiales diferentes al tabaco en sí, papel y filtro. Los aditivos del tabaco incluyen aromas artificiales, potenciadores del sabor, humectantes, azúcares, y compuestos de amonio. A pesar de que las compañías sostienen que los aditivos del tabaco no aumentan la toxicidad del humo y no hacen los cigarrillos más atractivos y adictivos, estas afirmaciones son cuestionadas por investigadores independientes. Este trabajo ha revisado los estudios sobre los efectos de los aditivos del tabaco en la química del humo y su toxicidad. Los aditivos del tabaco conllevan niveles más altos de formaldehído y otros cambios menores en los análisis realizados del humo. Estudios toxicológicos (tests de mutagenicidad en bacterias y citotoxicidad en mamíferos, ensayos de inhalación en ratas 90 días y células del micronúcleo de la médula ósea) mostraron que los aditivos del tabaco no aumentaron la toxicidad del humo. Los ensayos de roedores, sin embargo, no predijeron adecuadamente la carcinogenicidad del humo del tabaco, y no eran claramente suficientes para dar a conocer, sin embargo, las pequeñas, pero toxicológicamente relevantes, diferencias entre el test (con/aditivos del tabaco) y control (sin/aditivos del tabaco) en cigarrillos. Esta revisión de la literatura nos lleva a la conclusión de que el impacto dañino de los aditivos del tabaco en el humo continúa estando poco claro.

Abstract: Cigarette production involves a number of substances and materials other than just tobacco, paper and a filter. Tobacco additives include flavorings, enhancers, humectants, sugars, and ammonium compounds. Although companies maintain that tobacco additives do not enhance smoke toxicity and do not make cigarettes more attractive or addictive, these claims are questioned by independent researchers. This study reviewed the studies on the effects of tobacco additives on smoke chemistry and toxicity. Tobacco additives lead to higher levels of formaldehyde and minor changes in other smoke analytes. Toxicological studies (bacterial mutagenicity and mammalian cytoxicity tests, rat 90 days inhalation studies and bone-marrow cell micronucleus assays) found that tobacco additives did not enhance smoke toxicity. Rodent assays, however, poorly predicted carcinogenicity of tobacco smoke, and were clearly underpowered to disclose small albeit toxicologically relevant differences between test (with tobacco additives) and control (without tobacco additives) cigarettes. This literature review led to the conclusion that the impact of tobacco additives on tobacco smoke harmfulness remains unclear.

Women and tobacco: A total misfit or mis-unfit.

Women smokers are likely to increase as a percentage of the total. If the percentage of women who smoke in developing countries rise to the levels of men smokers, there will be more than 500 million women smokers in the next generation. Because women who smoke die from the same tobacco-caused diseases as men, such an increase will have dramatic effects on women's health and on the health and incomes of their families. In addition, women smokers are also at risk for developing cancer of the reproductive organs and osteoporosis. A gender perspective contributes to a better understanding of the epidemiological trends, social marketing strategies, economic policies, and international actions relating to women and the tobacco epidemic.

Evaluation of smoking genotoxicity in Turkish young adults.

BACKGROUND: For the past few decades, it has been widely known in developed countries that tobacco is dangerous, but it is still insufficiently realized how big these dangers really are. AIMS: To determine and evaluate micronuclei (MN) frequencies of young smokers and nonsmokers in three different tissues (peripheric blood lymphoctes, buccal mucosa, and exfoliative urothelial cells) at the same time. MATERIALS AND METHODS: MN assay was performed on buccal mucosa, urothelial cells, and peripheric blood lymphocyte samples obtained from 15 healthy male smokers (>5 pack-years) and 15 healthy male nonsmoker controls who had not been exposed to any known genotoxic agent. STATISTICAL ANALYSIS USED: The statistical differences between smoker and nonsmoker groups were calculated by using student t test. The differences between smoker-group tissues were compared by ANOVA. RESULTS: It was found that MN frequency (mean value ± standard deviation) in oral mucosa cells from smokers and controls were 1.20 ± 0.22% and 0.26 ± 0.10%; in urothelial exfoliative cells, 1.29 ± 0.28% and 0.12 ± 0.08%; in peripheric blood lymphocytes, 1.53 ± 0.23% and 0.38 ± 0.12%, respectively. The mean MN frequencies in buccal mucosa, urothelial exfoliative cells, and peripheric blood lymphocytes were significantly higher in smokers than in those of controls (P<0.05). All tissues were affected from smoking, but the most destructive effect was seen in urothelial cells of smokers (P<0.05). CONCLUSIONS: Our data showed that cigarette smoke is a DNA damage causitive agent on exfoliative buccal mucosa and urothelial cells and peripheric blood lymphocytes of young smokers, but it has most destructive effect on urothelial cells.

Effect of postnatal exposure to cigarette smoke on the tracheal epithelium of albino rat

Environmental tobacco smoke [ETS] is one of the most common indoor pollutants to which many children are exposed. The present work was carried out to investigate the his-ological changes of rat tracheal epithelium after postnatal exposure to cigarette smoke. Fifteen newborn albino rats were daily exposed to side-stream cigarette smoke [10 cigarettes a day, 6 days a week] for 12 weeks. From the trachea, paraffin sections were prepared and stained with Haematoxylin and eosin [H and E] stain and alcian blue-periodic acid-Schiff's stain [AB/PAS]. Toluidine blue stained semithin sections were also prepared and examined by light microscope. Ultrathin sections were processed for electron microscopic [EM] examination. In H and E stained sections the tracheal mucosa of the experimental animals showed erosion in the epithilium, oedema, and heavy mono-nuclear cellular infiltrate in the corium which resulted in polyp formation and decreased number of ciliated cells. Preneoplastic variants in the form of squamous metaplasia and dysplasia were also seen. AB/PAS stained sections revealed progressive increase in the number of goblet cells. Semithin sections showed increased number of globule leucocytes, basal cell hyperplasia and dysplasia. Electron microscope revealed swollen cilia, intracytoplasrmic cilia and loss of some basal bodies. Goblet cells were packed with numerous confluent mucus granules. Moreover, degenerated and apoptotic cells were also observed Therefore, it is strongly recommended to protect children from exposure to ETS and to warn parents about the hazards of continuous exposure of their children to cigarette smoke