Estimating the burden of lung cancer and the efficiency of home radon mitigation systems in some Canadian provinces ☆ Mo'tassem Al-arydah Department of General Education, Khalifa University of Science and Technology, Masdar Institute, Masdar City, P.O. Box 54224, Abu Dhabi, United Arab Emirates HIGHLIGHTS • Ontario and Quebec have the highest LC-burden and the highest LC caused by radon exposure. • Many cases of lung cancer in Canada and its provinces are associated with residential radon. • The BEIR VI assumption for US popula- tion, which states that 95% of lung cancer deaths in men and 90% of lung cancer deaths in women who are ever smokers, is applied to the Canadian population. • Population attributable risk is very sen- sitive to even small changes to radon mitigation systems in homes, which will affect many lives. The smaller the action level, the more sensitive the pop- ulation attributable risk to any small radon reduction. • The population attributable risk is linear in target radon values. GRAPHICAL ABSTRACT abstract article info Article history: Received 27 October 2017 Received in revised form 28 December 2017 Accepted 4 January 2018 Available online 19 February 2018 Editor: P. Kassomenos Lung cancer (LC) is the leading cause of death of cancer in Canada in both men and women, and indoor radon is the second leading cause of LC after tobacco smoking. The Population Attributable Risk (PAR) is used to assess radon exposure risk. In this work we estimate the burden of LC in some Canadian provinces. We use the PAR to identify the radon levels responsible for most LC cases. Finally, we use the PAR function of the two variables, radon action and target levels, to search for a possible optimal mitigation program. Methods: The LC burden for Ontario, Alberta, Manitoba, Quebec and British Columbia was estimated using provin- cial radon and mortality data. Then the PAR and LC cases for these provinces were estimated over the period 2006–2009 at different given indoor radon exposure levels. Finally, the PAR function when radon action levels and radon target levels are variables was analyzed. Results: The highest burden of LC in 2006–2009 was in Ontario and Quebec. During the period 2006–2009, 6% of houses in Ontario, 9% of houses in Alberta, 19% of houses in Manitoba, 7% of houses in Quebec, and 5% of houses in British Columbia had radon levels higher than 200 Bq/m 3 and were responsible about 913, 211, 260, 972, and 258 lives, respectively. Radon mitigation programs could have prevented these LC cases. The BEIR VI assumption for the United States (US) population, 95% of LC deaths in men and 90%of LC deaths in women are Ever-Smokers (ES), can be applied to the Canadian population. The PAR is a linear function in the target radon value with an Keywords: Lung cancer Radon gas Residential radon Attributable risk Sensitivity analysis Mitigation program efficiency Burden of disease Science of the Total Environment 626 (2018) 287–306 ☆ In memory of Professor Jan Zielinski E-mail address: malarydah@masdar.ac.ae. https://doi.org/10.1016/j.scitotenv.2018.01.028 0048-9697/© 2018 Elsevier B.V. All rights reserved. Contents lists available at ScienceDirect Science of the Total Environment journal homepage: www.elsevier.com/locate/scitotenv