Cigarette Smoke Toxins Deposited on Surfaces: Implications for Human Health

Abstract

Cigarette smoking remains a significant health threat for smokers and nonsmokers alike. Secondhand smoke (SHS) is intrinsically more toxic than directly inhaled smoke. Recently, a new threat has been discovered – Thirdhand smoke (THS) – the accumulation of SHS on surfaces that ages with time, becoming progressively more toxic. THS is a potential health threat to children, spouses of smokers and workers in environments where smoking is or has been allowed. The goal of this study is to investigate the effects of THS on liver, lung, skin healing, and behavior, using an animal model exposed to THS under conditions that mimic exposure of humans. THS-exposed mice show alterations in multiple organ systems and excrete levels of NNAL (a tobacco-specific carcinogen biomarker) similar to those found in children exposed to SHS (and consequently to THS). In liver, THS leads to increased lipid levels and non-alcoholic fatty liver disease, a precursor to cirrhosis and cancer and a potential contributor to cardiovascular disease. In lung, THS stimulates excess collagen production and high levels of inflammatory cytokines, suggesting propensity for fibrosis with implications for inflammation-induced diseases such as chronic obstructive pulmonary disease and asthma. In wounded skin, healing in THS-exposed mice has many characteristics of the poor healing of surgical incisions observed in human smokers. Lastly, behavioral tests show that THS-exposed mice become hyperactive. The latter data, combined with emerging associated behavioral problems in children exposed to SHS/THS, suggest that, with prolonged exposure, they may be at significant risk for developing more severe neurological disorders. These results provide a basis for studies on the toxic effects of THS in humans and inform potential regulatory policies to prevent involuntary exposure to THS.

Asymmetric dimethyl-arginine metabolism in a murine model of cigarette smoke-mediated lung inflammation

“…In the longer exposure experiments, animals were presented with whole-body mainstream and sidestream cigarette smoke via inhalation from 3R4F research cigarettes (Tobacco Health Research Institute, University of Kentucky, Lexington, KY) for 2 h/day, 5 days/week, for 4 weeks (WT, n ¼ 11-12; DDAH Tg, n ¼ 7-8). Utilizing the Teague small animal cigarette smoke exposure system, it has been demonstrated that the smoke generated from two packs of cigarettes per day in rodents produces a similar level of cotinine (Gentry-Nielsen et al, 2004) and nicotine (Martins-Green et al, 2014) metabolites as measured in equivalent human smoking. This amount of cigarettes is the equivalent of smoking one to two packs of cigarettes a day.…”

Biomarkers of disease can be detected in mice as early as 4 weeks after initiation of exposure to third-hand smoke levels equivalent to those found in homes of smokers

“…We have developed a model system in which the exposure of animals to THS mimics that of human exposure [6]. We found that THS causes alterations in multiple organ systems such as liver, lung, skeletal muscle, and healing of wounds which show various biomarkers of disease [6][7][8][9].…”

“…We found that THS causes alterations in multiple organ systems such as liver, lung, skeletal muscle, and healing of wounds which show various biomarkers of disease [6][7][8][9]. In the liver, we found that THS leads to increased lipid levels, indicating non-alcoholic fatty liver disease (NAFLD).…”

Environmental Damages of Tobacco: Only Human Being Damage?

“…Bu maruziyetin sağlık üzerindeki etkileri belirsizdir. Martins-Green ve arkadaşları bu maruziyetin biyolojik etkilerini farelerde değerlendirmişlerdir ve farelerin deri iyileşmesinde, davranışlarında, akciğer ve karaciğerlerinde ciddi hasarlanma meydana geldiğini bulmuşlardır (13) . Bu çalışmada farelerin kafesleri bir makine yardımıyla oluşturulan tütün dumanına 24-26 hafta, haftada beş gün ve günde altı saat maruz bırakılmış.…”