Environmental tobacco smoke exposure and brain development: the case of attention deficit/hyperactivity disorder.

Environmental tobacco smoke, inhaled by active firsthand smokers and their entourage, is associated with morbidity and mortality. Many children are passively exposed to secondhand smoke worldwide. Infants and young children account for the largest global disease burden associated with prenatal and postnatal secondhand smoke, probably due to underdeveloped neurological, immune, and respiro-circulatory systems. There is an increasingly robust association between tobacco smoke exposure, before and after birth, and executive function problems in children, adding to current and future disease burden estimates in public health. This review summarizes research advancements which address the link between environmental tobacco smoke and the development of attention deficits and hyperactive behavior, both as symptoms and as part of a mental health disorder in childhood. The multiple effects of tobacco smoke inhalation are best understood in terms of disruptions in normative processes involving cellular communication, structural development, and epigenetic influences which have the potential to become intergenerational. It is concluded that public health efforts be directed toward increasing parental awareness and compliance with existing guidelines that recommend no safe level of exposure.