All of the mothers and 95% of the fathers in the exposure group reported that their most heavily used tobacco product was cigarettes. During their period of heaviest use, these fathers averaged about 30 cigarettes and these mothers almost 25 cigarettes per day. Although there was a higher proportion of non-adopted relative to adopted adolescents who were exposed to parent smoking (59% vs. 48%, X2=5.81, p < .05), severity of risk indices within the exposure group were not associated with adoption status. That is, within the exposure group, non-adoptive mothers or fathers were no more likely to smoke currently than were adoptive mothers or fathers. Further, adopted and non-adopted adolescents were equally likely to have been exposed to more than one smoking parent.
