[Exposure to tobacco and cotinine levels in children].

Objective: To evaluate the exposure of children and their parents to cigarette smoke by measuring cotinine levels in saliva.

Patients: A total of 151 children (84 males and 67 females) aged 15 days to 17 years from hospital and extrahospital practices.

Method: Questionnaire on exposure to cigarette smoke from their parents, saliva cotinine levels by radioimmunoassay.

Results: Cotinine levels were higher in the passive smoker child than in the non-exposed child (p = 0.0001). A significant correlation was found between cotinine in the child and: a) total number of cigarettes smoked daily by both parents (p = 0.01); b) number of cigarettes smoked daily at home (p = 0.002), and c) number of cigarettes smoked at home in the 24 hours prior to sample obtention (p = 0.002). Higher levels of cotinine in the smoker parents than in the non-smoker parents were found (0.0001).

Conclusions: The passive smoker child has high cotinine levels in saliva which are directly related to the exposure degree.