To investigate the effects of environmental tobacco smoke exposure (second hand smoking) by healthy children by questionnaire method and the measurement of urine cotinine levels

Aim and Hypothesis: According to the recent Report by World Health Organization (WHO) on Tobacco, 700 million children exposure to tobacco smoke by 1.2 billion adult smokers in the world. Cigarette use rates in low- and middle-income nations are increasing. Tobacco use is linked to other high-risk behaviors. In Turkey, studies show that 53-85% children exposure to passive smoking. Cotinine is the most important and most reliable biological marker in smokers, nonsmokers and passive smokers. The aim of this study was to investigate passive smoking in healthy children younger than five years old, and to determine the adverse effects of second- hand smoking on child health. Methods: Children under five years old regularly monitored at the Child Health Surveillance Outpatient Clinic of Department of Pediatrics, Faculty of Medicine, Dokuz Eylul University, were included following informed consent by their parents and the questionnaire method was applied. Demographic variables related to family and children, respiratory tract infections, recurrent infections were asked in the questionnaire. The levels of cotinine and creatinine were measured and the cotinine / creatinine ratios were calculated in urine specimens taken from children participating in the study. Measurements of cotinine levels in urine specimens were performed by the Chemiluminescence Immunoassay Method in the Central Laboratory of the Faculty of Medicine Hospital. Using demographic data, cotinine / creatinine ratios in urine, the effects of secondhand tobacco smoke on children, growth status and infection frequency were determined. A licensed SPSS 22.0 package program was used for the statistical analysis of the data obtained in our study. Chi square Test and Mann- Whitney U Test were used to compare the proportional values of categorical variables. A p value of p <0.05 was considered statistically significant. Results: The ratio of household smokers was 47.8% and the number of non-smokers was 52.2%. Twenty seven per cent of the mothers were smokers. Urinary cotinine levels were found to be significantly higher in children of smokers compared with children of non-smokers (p = 0.01). One third (35.9%) of the children was evaluated as passive smokers. Although, cotinine/ creatinine ratios were higher in children of smokers, the difference was not significant. On the other hand, head circumference of children of smokers were found significantly small compared to children of non-smokers(p = 0.004),specially in children of mothers smoke during pregnancy. Conclusion: In this regularly monitored preschool children, we found frequent exposure to cigarette smoke. The presence of exposure can be deduced from urinary cotinine / creatinine ratios in addition to information from the parents. This study contributes to national data on the subject and will aid in increasing the awareness in families to the deleterious effects of secondhand smoking on child health. Identification of harmful consequences associated with second-hand smoking in children that we know to be common in Turkey, gives a more reliable data on this issue and will help to raise awareness in the community. All women should be specifically counseled to abstain from the use of tobacco as well as the use of alcohol and illicit drugs during pregnancy. Keywords: Environmental tobacco smoke, secondhand smoking, child, cigarette, urine cotinine