A study to be published in the Journal of Developmental and Behavioral Pediatrics examined the possible impact of exposure to secondhand smoke on children’s behaviour. Although most studies of this kind rely on parents’ reports of smoke exposure, researchers in this case measured it using tests that detect cotinine, a byproduct of nicotine, in the bloodstream. Children were recruited from an asthma intervention trial.
Although girls were exposed to more smoke than boys were, only boys showed a significant increase in behaviour problems. These difficulties included externalizing behaviours (e.g., hyperactivity, aggression) and internalizing problems (e.g., depression). Behaviours were more severe with increasing smoke exposure.
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