Passive cigarette smoke exposure in primary school children in Liverpool.

OBJECTIVE

To assess environmental tobacco smoke (ETS) exposure amongst primary school children.

METHODS

A descriptive, community-based, cross-sectional study of self-reported parental smoking patterns and children's salivary cotinine concentrations in 245 children aged 5-11 years attending 10 primary schools in Liverpool.

RESULTS

The mean age was 7.4 years. The percentage of children living in smoking households was higher than the average reported for England (61.4% vs 53.0%). The average daily number of cigarettes smoked was similar for fathers (15.8) and mothers (16.4). The mean salivary cotinine concentration (+/-SD) was 1.6+/-0.4 ng/ml, and was higher in boys than girls (1.9+/-0.4 vs 1.2+/-0.2 ng/ml, P=0.006). The mean cotinine concentration was higher amongst children less than 7 years of age compared with older children (1.9+/-0.9 vs 1.4+/-0.6 ng/ml, P=0.01). Children from disadvantaged socio-economic households (Townsend score > + 6) had a mean cotinine level of 1.9+/-0.4 ng/ml, and a higher risk of a positive cotinine-validated level (>or=1 ng/ml) [crude odds ratio (OR) 3.5, 95% confidence interval (CI) 1.6-5.2). Maternal, but not paternal, cigarette smoke exposure was significantly associated with the salivary cotinine-validated level in children (adjusted OR 2.5, 95%CI 1.8-3.4).

CONCLUSIONS

Maternal smoking, age less than 7 years, child's gender (male) and low socio-economic status were significant risk factors associated with ETS exposure in young school children in Liverpool. The level of childhood ETS exposure in this area demonstrates a major public health concern that creates a challenge for innovative interactive strategies.