Seasonality of 214Bi activity in the human body and of 222Rn concentration in home ambient air

We studied the seasonal variation of the environmental radon progeny (214)Bi activity in the whole bodies (WB) of women and men participating in community-based studies at the Grand Forks Human Nutrition Research Center (GFHNRC), the (214)Bi background activity of the GFHNRC whole body counter (WBC) steel room, and ambient air (222)Rn concentration in the homes of Grand Forks residents, over the 1988-2004 time period. In this cross-sectional epidemiological study, (214)Bi activity in women and men, in the WBC steel room, and (222)Rn concentration in resident homes fluctuated such that the highest values were observed in winter and the lowest in summer, respectively. (214)Bi activity in the WB of human subjects was higher in women who have more (214)Bi activity per unit mass than men. Apart from their common seasonal pattern, human WB (214)Bi activity (lnBq) was comparatively higher than that for the ambient air (222)Rn activity in a human-equivalent volume of 72 L.