²¹⁰Po implanted in glass surfaces by long term exposure to indoor radon

Authors

Daniel J. Steck, College of Saint Benedict/Saint John's UniversityFollow
M. C. R. AlavanjaFollow
R. W. Field
M. A. Parkhurst
D. J. Bates
J. A. Mahaffey

Document Type

Article

Publication Date

8-2002

Disciplines

Health and Medical Physics | Physics

Abstract

Recent epidemiologic investigations of the relationship between residential radon gas exposure and lung cancer relied on contemporary radon gas measurements to estimate past radon gas exposures. Significant uncertainties in these exposure estimates can arise from year-to-year variation of indoor radon concentrations and subject mobility. Surface implanted ²¹⁰Po has shown potential for improving retrospective radon gas exposure estimates. However, in previous studies, the ability of implanted ²¹⁰Po activity to reconstruct cumulative radon gas exposure was not tested because glass was not available from homes with known radon-gas concentration histories. In this study, we tested the validity of the retrospective radon gas reconstruction using implanted ²¹⁰Po surface activity by measuring glass surfaces from homes whose annual-average radon gas concentrations had been measured almost every year during two decades. Regression analysis showed a higher correlation between measured surface activity and cumulative radon gas exposure in these homes (R²>0.8) than was observed in homes where only contemporary radon gas measurements were available. The regression slope (0.57 ky m^-1) was consistent with our earlier retrospective results. Surface activity measurements were as reliable for retrospective radon gas exposure reconstruction as yearlong gas measurements. Both methods produced estimates that were within 25% of the long-term average radon gas concentrations in a home. Surface measurements can be used for home screening tests because they can provide rapid, reliable estimates of past radon gas concentrations. Implanted ²¹⁰Po measurements are also useful in retrospective epidemiologic studies that include participants who may have been exposed to highly variable radon concentrations in previously occupied or structurally modified homes.

Recommended Citation

Steck DJ, Alavanja MCR, Field RW, Parkhurst MA, Bates DJ, Mahaffey JA. 2002. ²¹⁰Po implanted in glass surfaces by long term exposure to indoor radon. Health Physics 83(2): 261-271.