"Among children ages 6-11 who live with smokers, one quarter to one-third of school absences are due to household smoking," lead author Douglas Levy of the Mongan Institute for Health Policy at Massachusetts General Hospital says in a statement. "On a national basis these absences result in $227 million in lost wages and time for caregivers or their employers."
One-third of U.S. children live with at least one smoker, and more than half of those ages 3-11 have detectable levels of a blood marker for tobacco exposure, Levy says.
"Secondhand smoking has been shown to increase incidence of ear infections and several respiratory conditions and school absenteeism is an accessible measure of serious illness in children," Levy says.
The research team analyzed data from the 2005 National Health Interview Study, an annual in-person survey of representative households nationwide.
Of the 3,087 children observed in the study, more than 14 percent lived in a home with at least one person who smoked in the house -- 8 percent living with one household smoker and 6 percent with two or more -- representing 2.6 million children nationwide.
The study, published in the online edition of Pediatrics, finds children living with one in-home smoker had an average of 1.06 more days absent, and those living with two or more had 1.54 more days absent, than did children living in homes where no one smoked indoors.