How home-smoking habits affect children: A cross-sectional study using urinary cotinine measurement in Italy

To assess the impact of different home-smoking rules and smoking habits of cohabitant on environmental tobacco smoke (ETS) exposure of children. Information about 396 Italian children (5-11 years old) and cohabitants' smoking habits was collected by a questionnaire. Exposure assessment was performed by determination of urinary cotinine (u-cotinine). Median u-cotinine concentrations in children significantly increased in a similar fashion as theoretical ETS exposure increase: cohabitants do not smoke (1.79 mu g/g creatinine), cohabitant(s) smoker(s) never smoke at home (2.84), smoke at home only when children are out (3.90), and smoke at home even if children are in (6.02). Median u-cotinine levels of exposed children were associated to the strength of cohabitant's smoking behaviours when smoker(s) consume daily a high number of cigarettes (a parts per thousand yen 20) respect to light consumption (1-9) (4.52 and 3.24 mu g/g creatinine). The magnitude of ETS exposure in children is correlated with smoking habits and home-smoking precautions adopted by their cohabitants. Educational interventions on parents are essential to increase their awareness about ETS exposure and to teach correct behaviours to protect health of kids, especially in household environment.