Non-smokers are exposed to second hand smoke (SHS) at home, at work, and in the community. Although they are not smoking themselves, this still creates significant health risks for them. The smoke lingers in the air for several hours and contains numerous toxic chemicals including benzene, carbon monoxide, chromium, cyanide, formaldehyde, lead, and nickel. A recent study has found that SHS raises the risk of neurodevelopmental disorders like attention deficits and learning disabilities.

Children exposed to secondhand smoke at home had a striking 50% increased risk of having one or more neurobehavioral disorders compared with children who were not exposed to SHS.

It is estimated that roughly 5.5 million (7.6%) US children live in households in which someone smokes. Secondhand smoke's (SHS) affects children more severely than adults. It has been linked to a multitude of health problems such as sudden infant death syndrome, acute respiratory infections, ear problems, asthma, heart disease, and cancers. Now neurodevelopmental problems have been added to the mix.

The study examined the impact of childhood secondhand smoke exposure on the occurrence of neurodevelopmental problems in young children. Researchers assessed 55,358 children up to age 11 by phone interview with their parents. (The cut- off age of 12 was established to eliminate children who were themselves smokers.) They obtained histories of ADHD, learning disabilities, conduct /behavioral disorders, and the need for therapy or psychological treatment.

Neurodevelopmental disorders place a huge burden on the individual, our educational and health care systems, and society as a whole. Children with ADHD have developmentally inappropriate levels of inattention and hyperactivity. Learning disabilities (LD) are found in people who have average intelligence but abnormal abilities to receive, process, store and respond to information. For example, they might have difficulties with reading, memorizing, and explaining information. Behavior and conduct disorders are persistent negative patterns of behavior that carry an increased risk for drug and alcohol abuse, antisocial personality disorder and anxiety related disorders.

There are many known and suspected causes for the neurodevelopmental disorders of childhood including socioeconomic factors, prenatal health, birth and early childhood health issues and exposures, and genetic vulnerabilities. Researchers compared the occurrence of neurodevelopmental disorders to the children’s secondhand smoke exposure, controlling for other high demographic risk factors such as family economics and education.

They found that children exposed to SHS at home had a striking 50% increased risk of having one or more neurobehavioral disorders compared with children who were not exposed to SHS. Boys exposed to smoke had a significantly higher risk and older children, especially those aged 9-11 years and those living in households with the highest poverty levels were at greatest risk of being negatively impacted by SHS. Their results suggested that second hand smoke had accounted for 274,000 cases of ADHD, learning disabilities, and behavioral or conduct disorders in the period from 2007-2008.

The message is clear. Along with causing numerous acute and chronic physical ailments from ear infections to cancers, second hand smoke is strongly associated with ADHD, learning disabilities, conduct and behavior disorders and the need for counseling in children. Parents are advised to monitor and avoid their children’s secondhand smoke exposures both in and away from the home as there has been no safe level established for exposure.

The study was published in the July 11 issue of Pediatrics.