Approximately 1 billion tons of phosphogypsum (PG), a by-product of the fertilizer industry, are currently stacked in Florida. PG emits radon gas, which is a risk factor for lung cancer and can also increase particulate matter (PM) associated non-cancer mortality in exposed individuals. We measured concentrations of atmospheric radon and particulate matter near PG stacks and their short-term variations at different distances to estimate exposures in nearby communities. Specifically, we measured atmospheric levels of radon, and mass concentrations of PM₁, PM_2.5, and PM₁₀, and number concentrations of PM_0.3, PM_0.5, PM_1, PM_2.5, PM₅, and PM₁₀ near three large PG stacks in Florida. Atmospheric radon was collected at distances of 2.5, 5.0, and 7.5 miles downwind from three large PG stacks using charcoal-based kits and measured by liquid scintillation counting. A professional radon monitor was used to take 24-h-average radon reading at 5.0 miles from each stack for comparison purposes. The median (IQR) radon levels were 0.325 (0.150, 0.675), 0.150 (0.150, 0.650), and 0.500 (0.150, 0.700) pCi/L at 2.5, 5, and 7.5 miles, respectively. The median (IQR) PM_2.5 levels were 5 (4, 6), 5 (3, 7), and 5 (2, 9) µg/m³ at 2.5, 5, and 7.5 miles, respectively. Non-parametric Kruskal-Wallis test could not detect any association between radon or PM levels and distances (2.5–7 miles) from PG stacks. With scintillation counting, median radon levels detected were above the US Environmental Protection Agency (EPA) recommended standard in some of the sites; however, much higher levels were detected through the more advanced digital monitor. PM_2.5 levels were below the US-EPA 24-h average national ambient air quality standard in the study area. We conclude that ambient radon levels near PG stacks could exceed US EPA recommended outdoor standards and do not vary within a short distance from the sources, implying similar exposures in nearby communities.

目前，在佛罗里达州堆积了约10亿吨磷石膏（PG），这是化肥行业的副产品。PG释放出gas气，这是肺癌的危险因素，并且还可能增加暴露个体中与微粒物质（PM）相关的非癌症死亡率。我们测量了PG烟囱附近的大气ra和颗粒物的浓度及其在不同距离的短期变化，以估计附近社区的暴露程度。具体来说，我们测量了大气中的levels水平，PM ₁，PM _2.5和PM _10的质量浓度以及PM _0.3，PM _0.5，PM _1， PM _2.5，PM _5的数量浓度，以及位于佛罗里达的三个大型PG烟囱附近的_10号纸机。使用基于木炭的试剂盒从三个大型PG烟囱沿下风向2.5、5.0和7.5英里处收集了大气ra，并通过液体闪烁计数进行了测量。为了进行比较，使用了专业的ra监测仪，以距每个烟囱5.0英里的距离获取24小时平均ra读数。在2.5、5和7.5英里处，中位数（IQR）C水平分别为0.325（0.150，0.675），0.150（0.150，0.650）和0.500（0.150，0.700）pCi / L。PM _2.5的中位数（IQR）为5（4、6），5（3、7）和5（2、9）µg / m ³分别位于2.5英里，5英里和7.5英里处。非参数Kruskal-Wallis检验无法检测到ra或PM水平与距PG烟囱的距离（2.5-7英里）之间的任何关联。通过闪烁计数，在某些站点中检测到的median中位数水平高于美国环境保护署（EPA）推荐的标准；但是，通过更高级的数字监视器可以检测到更高的级别。研究区域的PM _2.5含量低于美国-EPA 24小时平均国家环境空气质量标准。我们得出的结论是，PG烟囱附近的环境ra水平可能会超过美国EPA建议的室外标准，并且在与排放源的短距离内不会发生变化，这意味着附近社区的暴露程度相似。