Association between parental smoking and child exposure to environmental tobacco smoke in Israel

Background Environmental tobacco smoke (ETS) exposure in children can cause delayed lung development and lifelong cardiovascular damage. The aim of this study was to measure ETS exposure in children in Israel in 2020–2021 using urinary cotinine (UC) measurements and to assess correlates of ETS exposure, including parental smoking. Methods In the framework of the National Human Biomonitoring Program, spot urine samples and questionnaire data were collected from 166 children aged 4–12 years, during the years 2020–2021. We collected urine samples in 233 adults, 69 of whom were parents of children included in the study. Parents of participating children were asked about parental smoking, child’s exposure to ETS and smoking policy at home. Cotinine and creatinine were measured in urine. Creatinine-adjusted and unadjusted urine cotinine (UC) geometric means were calculated. Associations between potential correlates and UC concentrations were analyzed in univariate and multivariate analyses. For 69 child-parent pairs, correlation between child and parental UC was analyzed. Results Based on urinary cotinine measurement, 65.2% of children of smokers are exposed to ETS, compared to 20.7% of children in non-smoking families. Greater numbers of smokers living in the home (beta = 1.27, p < 0.01), and low maternal education (beta = − 2.32, p < 0.01) were associated with higher levels of UC in a multivariate analysis. Spearman correlations showed a positive moderate correlation between UC in 69 child–parent pairs (r = 0.52, p < 0.01). Conclusions In order to reduce child exposure to ETS, smoking parents should be urgently targeted for smoking cessation and smoke-free home interventions. Further interventions are needed to protect all children from ETS.