Table 1.

Studies on residential radon exposure and skin cancer risk.

Country	Author	Study Design	Mean Follow-Up	Sample Size	Exposure	Radon Exposure Measurements	Risk Estimate (95% CI)
Switzerland	Vienneau (2017)23	Cohort	7.8 years	5.2 million subjects; 1,900 MM cases	Per 100 Bq/m3	Address-level exposure estimated by national exposure prediction model	HR:1.16 (1.04, 1.29)
Denmark	Bräuner (2015)22	Cohort	13.6 years	51,445 subjects; 3,889 cases (3,243 BCC, 317 SCC, 329 MM)	Per 100 Bq/m3	Address-level exposure estimated by validated regression model	BCC IRR:1.14 (1.03, 1.27) SCC IRR:0.90 (0.70, 1.37) MM IRR:1.08 (0.77, 1.50)
Spain	Barbosa-Lorenzo (2016)20	Cohort	30.2 years	1933 subjects; 25 skin, except melanoma, cancer cases	≥50 Bq/m3	Bedroom-level exposure from Galicia Radon Map*	HR:1.5 (0.6, 3.8)
United States	Turner (2012)19	Cohort	20.4 years	811,961 subjects; 2,098 cases (1,247 MM, 538 connective tissue malignant neoplasm, 313 other skin malignant neoplasm) (all mortality)	Per 100 Bq/m3 radon	County-level exposure estimated by empirical study model	MM HR:1.08 (0.88, 1.33) Connective Tissue Malignant Neoplasm Mortality HR:1.10 (0.80, 1.51) Other Skin Malignant Neoplasm Mortality HR:0.70 (0.42, 1.19)
United Kingdom	Wheeler (2012)21	Ecological Surveillance	Period: 2000-2004 (cancer incidence); 1980-2000 (radon)	18,306 cases	≥230 Bq/m3 radon vs 0-39 Bq/m3	Postcode sector-level exposure obtained from National Radiologic Protection Board**	BCC RR:0.81 (0.66, 1.00) SCC RR:1.76 (1.46, 2.11) MM RR: 0.85 (0.65, 1.11)

CI, confidence interval; MM, malignant melanoma; HZ, hazard ratio; BCC, basal cell carcinoma; SCC, squamous cell carcinoma; IRR, incidence rate ratio; RR, relative risk, *Galician Radon Map measurements obtained from radon detectors placed in study participants’ bedrooms for a minimum of three months, **National Radiologic Protection Board radon atlas measurements were obtained through radon detectors placed in surveyed households