Thirdhand smoke exposure and its toxicological impacts: A review on target organ based studies

Third-hand smoke (THS) is a newly described environmental health hazard that might be defined as a residual cigarette smoke that occurs due to the accumulation of toxins of second-hand smoke (SHS) in the smoking environment. In addition, chemicodynamic of THS may alter due to the interaction with other gases and chemicals present in the environment. THS may cause serious health outcomes in the lungs, liver, skin, heart, and nervous system as well. Hence, it is thought to represent a major health hazard for people, particularly for children, whom exposed to THS where they interact more frequently with these surfaces exposed to THS via hand to mouth transfer. In the present study, it was aimed to summarize the proposed toxicity mechanisms based on in vitro and in vivo studies based on target organ toxicity. In this study, it is aimed to review toxicity mechanisms of THS based on in vitro and in vivo studies on target organ toxicity. Recent studies reported that THS might induce unwanted effects in the respiratory, cardiovascular, nervous, hematopoietic, and skeletal systems and skin. Literature data indicated that THS-mediated oxidative damage and increase in inflammatory response may play an important role in the pathogenesis of cardiovascular and neurobehavioral diseases, especially the target organ lung, and in the future, THS might be defined as a preventable environmental risk factor. Therefore, further studies on THS are needed to define its toxicity mechanism as well as increase the social awareness and legal regulations.