{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,16]],"date-time":"2026-10-16T04:13:48Z","timestamp":1792124028385,"version":"4.4.0"},"reference-count":73,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2019,5,21]],"date-time":"2019-05-21T00:00:00Z","timestamp":1558396800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Southern Florida is underlain by rocks and sediments that naturally contain radioactive isotopes. The primary origin of the radioactive isotopes is Miocene-aged phosphate deposits that can be enriched in uranium-238 and its daughter isotopes. Nodular phosphate containing radionuclides from the Miocene has been reworked into younger formations and is ubiquitous in southern Florida. When the nodular phosphate is exposed to groundwater with geochemical conditions favorable for its dissolution, uranium, radium, and radon may be released into the groundwater system. Uranium concentrations have been measured above the 30 \u00b5g\/L drinking water standard at only one location in Lee County. Radium226\/228 exceedances of the drinking water standard have been documented in numerous wells in Sarasota County. Indoor radon activities have exceeded the 4 piC\/L guideline in five southern Florida counties. The exceedance of radioactivity standards in drinking water does not occur in municipal drinking water supplies, but rather only in some domestic self-supply wells. Health risks for exposure to radiation from domestic self-supply wells could be mitigated by testing of well water and, if necessary, switching to the use of a different aquifer or treatment process. While the risk of exposure to radon in indoor air in southern Florida is generally low, some areas are enriched in soil radon that migrates into structures, which could be addressed by improved ventilation.<\/jats:p>","DOI":"10.3390\/ijerph16101793","type":"journal-article","created":{"date-parts":[[2019,5,21]],"date-time":"2019-05-21T10:52:51Z","timestamp":1558435971000},"page":"1793","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":84,"title":["Natural Radiation in the Rocks, Soils, and Groundwater of Southern Florida with a Discussion on Potential Health Impacts"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5435-8233","authenticated-orcid":false,"given":"Thomas M.","family":"Missimer","sequence":"first","affiliation":[{"name":"Emergent Technologies Institute, U. A. Whitaker College of Engineering, Florida Gulf Coast University, 16301 Innovation Lane, Fort Myers, FL 33901, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christopher","family":"Teaf","sequence":"additional","affiliation":[{"name":"Center for Biomedical and Toxicological Research, Florida State University, Tallahassee, FL 32310, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert G.","family":"Maliva","sequence":"additional","affiliation":[{"name":"Emergent Technologies Institute, U. A. Whitaker College of Engineering, Florida Gulf Coast University, 16301 Innovation Lane, Fort Myers, FL 33901, USA"},{"name":"WSP USA Inc., 1567 Hayley Lane, Suite 202, Fort Myers, FL 33907, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ashley","family":"Danley-Thomson","sequence":"additional","affiliation":[{"name":"U. A. Whitaker College of Engineering, Department of Environmental and Civil Engineering, 10501 FGCU Boulevard South, Fort Myers, FL 33965-6565, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Douglas","family":"Covert","sequence":"additional","affiliation":[{"name":"Hazardous Substance and Waste Management Research, 2976 Wellington Circle West, Tallahassee, FL 32309, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Hegy","sequence":"additional","affiliation":[{"name":"Emergent Technologies Institute, U. A. Whitaker College of Engineering, Florida Gulf Coast University, 16301 Innovation Lane, Fort Myers, FL 33901, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,5,21]]},"reference":[{"key":"ref_1","unstructured":"U.S. National Academy of Sciences, National Research Council, and Committee to Assess Health Risks from Exposure to Low Levels of Ionizing Radiation (2006). Heath Risks to Exposure to Low Levels of Ionizing Radiation, BEIR VII Phase 2, National Academies Press."},{"key":"ref_2","unstructured":"U.S. Environmental Protection Agency (2012). Radiation: Facts, Risks, and Realities."},{"key":"ref_3","unstructured":"National Council on Radiation and Measurements (2006). Ionizing Radiation Exposure of the Population of the United States."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Sutcliffe, H., and Miller, R. (1981). 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