Background:Smoking remains a major public health problem in Türkiye. Among individuals aged 15 years and older, the average daily cigarette consumption is 17.1 cigarettes, indicating a high level of tobacco use. Smoking represents a substantial burden in terms of disability-adjusted life years (DALYs) and is a major risk factor for lung cancer and more than 50 other cancers. Evaluating smoking behaviors among young populations is therefore critical for cancer prevention. In addition, awareness of third-hand smoke (THS) a form of tobacco exposure that remains poorly recognized even among health professionals has not been sufficiently studied. Medical students, as future doctors who will inform society about health risks, must have a comprehensive understanding of the harms of smoking from a public health perspective.
Objectives:This study aimed to investigate smoking behaviors and evaluate the level of awareness regarding third-hand smoke (THS) among medical students. By identifying sociodemographic and behavioral factors associated with nicotine dependence and THS awareness, the study seeks to contribute to preventive strategies and educational interventions in public health and medical education.
Methods:This descriptive and cross-sectional study was conducted among students of Bezmialem Vak?f University Faculty of Medicine in Istanbul. Data were collected using a 31-item questionnaire assessing sociodemographic characteristics, smoking behavior, and awareness of third-hand smoke. Nicotine dependence was measured using the Fagerström Test for Nicotine Dependence, while THS awareness was assessed using a 9-item scale with two subdimensions: health effects and environmental persistence. A total of 112 students voluntarily participated in the study. 
Results:Among the participants, 58.9% were female and 41.1% were male. The prevalence of current smoking was 30.4%, while 42.9% reported never having smoked. According to the Kolmogorov–Smirnov test, nicotine dependence and THS awareness scores were not normally distributed (p<0.05); therefore, non-parametric tests were applied. Nicotine dependence levels differed significantly by economic status (p=0.001) and alcohol consumption (p=0.000). Students whose income equaled their expenses had higher dependence scores (mean=4.89), and non-alcohol users had higher scores (mean=5.27). No significant differences were observed by gender, academic year, chronic illness, medication use, parental smoking status, or in-home smoking exposure (p>0.05). THS awareness levels differed significantly only according to whether participants considered prior indoor smoking when purchasing homes or vehicles (p=0.000), with higher awareness scores among those who did (mean=39.39) compared with those who did not (mean=33.00). No significant differences in THS awareness were observed across other variables (p>0.05).
Conclusions: Economic perception and alcohol consumption were significant factors associated with nicotine dependence, while sensitivity to environmental tobacco exposure was associated with higher third-hand smoke awareness. These findings highlight the need to strengthen tobacco-related education and third-hand smoke awareness among future doctors. Targeted educational and preventive interventions during medical training may play a key role in reducing tobacco-related harm and supporting cancer prevention efforts in the wider population.