Among children with asthma, exposure to ETS is related to increased child behavior problems among boys..

February 21, 2009 - Emerging evidence suggests that exposure to environmental tobacco smoke (ETS, passive smoking, second hand smoke, involuntary smoking) may be linked with behavior problems in childhood, but previous research has relied primarily on parent report of exposure, and results are inconclusive. Boys with asthma who are exposed to environmental tobacco smoke have higher degrees of hyperactivity, aggression, depression, and other behavioral problems - behavioral problems increased with exposure levels

PAPER: Yolton, Kimberly PhD; Khoury, Jane PhD; Hornung, Richard DrPH; Dietrich, Kim PhD; Succop, Paul PhD; Lanphear, Bruce MD, MPH Environmental Tobacco Smoke Exposure and Child Behaviors [Original Article]Journal of Developmental & Behavioral Pediatrics:Volume 29(6)December 2008pp 450-457 ABSTRACT..

Among 220 children in the study, 61% were boys, 56% were black, and 77% had moderate to severe asthma, with the rest having mild asthma. Children included in the study had to have a diagnosis of asthma with no other health problems and be exposed to at least five cigarettes a day. According to estimates provided by parents, children were exposed to an average of 13 cigarettes a day. Because parental estimates can be inaccurate, says Yolton, investigators also measured the cotinine levels in the children's blood. (Cotinine is a byproduct, or metabolite, of nicotine and is often used as a biomarker to more accurately measure tobacco smoke exposure.) Behavioral patterns were reported by parents using the Behavioral Assessment System for Children.

Stronger efforts are needed to prevent childhood exposure to tobacco smoke..

Reference: Research Links Behavior Issues in Asthmatic Boys to Tobacco, 2/21/2009.