| Abstract: | Concentrations of airborne radon ranging from 0.05 to 135 pCi/L were found in houses in Maine. Tracketch cups were placed in five positions for 100 houses to determine integrated average radon concentrations over the period October 1980–May 1981. To investigate the association between elevated radon concentrations in well water and the indoor airborne radon concentrations, the radon in the water supplies of these houses was measured by liquid scintillation. Monitors of airborne radon, recording in intervals of 10 min for periods of 5–7 days, were used for dynamic studies in 18 houses, determining the component of airborne radon associated with major water uses, such as showers, laundry, and dishwashing, which liberate radon in bursts. House residents kept logs noting the time of major water uses. For some of the houses, ventilation rates ranging from 0.3 to 2 air changes per hour were determined by analysis of the dynamic data. The component of airborne radon associated with water sources was found to vary inversely with ventilation rate and directly with waterborne radon concentration, with 0.8 ± 0.2 pCi Rn/L air per nCi Rn/L water at a ventilation rate of 1.0 air change per hour. The data are pertinent to a study which has revealed significant correlations between county averages, from the National Cancer Institute, or age-adjusted cancer mortality rates in Maine and average values of radon concentrations in water for the counties. |
