Factors modifying exposure to environmental tobacco smoke in children (Athens, Greece).

The aim of the study was to investigate individual, family, and environmental factors which may modify exposure of children to environmental tobacco smoke (ETS). A total of 2,108 children of both genders, aged up to 14 years old, were enrolled in the study. Parents of the children provided information concerning several factors that may affect exposure to ETS. Cotinine-to-creatinine ratios in spot urine samples were measured for each child. These values were logtransformed and regressed on a series of exposure variables. Among children, 73 percent were exposed to ETS generated by at least one smoker in the household. Exposure to ETS was affected by the following factors: cigarettes smoked by parents while the child was at home (increase by 37 percent per 10 cigarettes daily, 95 percent confidence interval [CI] = 32-43 percent); precautions taken by parents (no cf yes, increase by 38 percent, CI = 24-54 percent); child's age (decrease by nine percent per year, CI = -11-8 percent); gender (male lower than female by 13 percent, CI = -21-3 percent); day of the week (Monday cf Tuesday-through-Sunday, increase by 28 percent, CI = 14-44 percent); floor surface area (decrease by nine percent per 20 m2, CI = -14-5 percent); heating (central cf non-central decrease by 14 percent, CI = -25-2 percent); maternal education (decrease by nine percent per five years, CI = -18-0 percent); paternal education (decrease by seven percent per five years, CI = -15-2 percent). It is concluded that several household-related factors affect exposure to ETS and that this exposure can be reduced by about one-third by simple precautions taken by smoking parents.

Objective passive-smoking indicators and respiratory morbidity in young children.

Exposure to environmental tobacco smoke is associated with increased respiratory morbidity in young children, but few studies have assessed such exposure objectively by urinary cotinine measurements. 501 children aged 1-5 years, a random 5% sample of children attending an outpatient clinic, were classified as exposed or non-exposed to environmental tobacco smoke with a cut-off of 10 ng cotinine per mg creatinine in urine. Exposed children were 3.5 times (95% CI 1.56-7.90, p < 0.0024) more likely to have increased respiratory morbidity (three or more episodes during the previous 12 months) than non-exposed children after adjustment for potential confounding factors.