Infant exposure to environmental tobacco smoke: a prevalence study in Australia.

OBJECTIVE: To determine: the prevalence of exposure to environmental tobacco smoke among infants aged 0-12 months in two child health care settings; the accuracy of parent report indicators of exposure; and the factors associated with exposure to environmental tobacco smoke.
METHOD: Samples of consecutive parents of infants 12 months of age or younger who attended Hunter Region public child health and immunisation clinics were approached to complete a questionnaire and to allow a urine sample to be obtained from their infant during December and January 1998/99. Infant urine samples were analysed for cotinine and information obtained regarding the smoking status of household members, infant exposure to environmental tobacco smoke during the previous three days, and parent and infant characteristics and demographics.
RESULTS: 85 (47%) [95% CI 40-54] infants in the combined sample had detectable levels of cotinine. Sensitivity of reported infant exposure of 86% was achieved through the combined measure of parent report of exposure and smoking status of households. The odds of exposure for infants of smoking parents were 14 times that of infants of nonsmokers [CI 5.26-50.0].
CONCLUSIONS: Almost half of the infants in this study had detectable levels of cotinine in their urine. Future interventions targeting infant exposure to environmental tobacco smoke should incorporate quit smoking strategies for both parents and other household members, as well as strategies for changing the pattern of smoking behaviour around infants. IMPLICATIONS: These findings suggest that existing community education strategies and passive smoking public policies are failing to protect this vulnerable population group.