Using willingness to pay to evaluate the implementation of Canada's residential radon exposure guideline.

BACKGROUND The objective of this investigation was to determine the effectiveness of Canada's residential radon exposure guideline in influencing individuals' health protection decisions. METHOD Homeowners with known exposure levels in a high residential radon area (Winnipeg, Manitoba) were surveyed to document what they had done and spent to reduce their exposure to radon. The 507 respondents were then re-surveyed to elucidate their response to hypothetical scenarios. Logistic regression was used to model risk reduction decisions as a function of exposure and other explanatory variables. RESULTS Homeowners were only likely to have taken action to reduce exposure at levels exceeding 1,100 Bq/m3, well above Canada's guideline of 800 Bq/m3. However, when informed of the guideline, respondents indicated they would act at exposures of 702 Bq/m3. INTERPRETATION The Canadian residential radon exposure guideline, as it has been implemented, has not effectively prompted homeowner actions to reduce exposures to radon.