Estimating population lung cancer risk from radon using a resource efficient stratified population weighted sample survey protocol - Lessons and results from Ireland.

A 2018 estimate indicates that there were 226,057 radon-attributable lung cancer deaths in 66 countries that had representative radon surveys. This is a shocking figure, and as it comes from only 66 countries it underestimates the worldwide death toll. Any research that enables countries to conduct representative radon surveys and to understand better the risk to citizens from radon is surely welcome. We hope this paper provides a useful methodology for estimating population risk. The estimation of population weighted average indoor radon levels requires statistically valid sampling methodologies that use a representative sample of occupied homes throughout the country. A literature review indicates that in many population weighted surveys, the sampling methodology may not have been designed to do this. This paper describes a simple, resource efficient methodology which produces statistically valid and reliable estimates based on a small scale sample that is representative of the population distribution. The resource efficient design of this study enables it to be repeated at frequent intervals providing for a longitudinal analysis of the population risk from indoor radon. This survey was conducted in Ireland using 653 measurements and a representative sampling strategy to provide a baseline population weighted radon exposure for future comparisons. This study estimates the average population weighted indoor radon concentration in Ireland to be 97.83 Bq m-3 (95% Confidence Interval 90.69 Bq m-3 to 105.53 Bq m-3), and that there are an estimated 350 lung cancer cases and 255 deaths per year due to radon exposure. The mortality rate of 5.3 per 100,000 due to indoor radon, demonstrates that radon remains one of the highest preventable causes of death in Ireland.