Elevated levels of radiocarbon in methane dissolved in seawater reveal likely local contamination from nuclear powered vessels
Elevated levels of radiocarbon in methane dissolved in seawater reveal likely local contamination from nuclear powered vessels
复制标题
溶解在海水中的甲烷中放射性碳含量升高表明核动力船舶可能造成局部污染
DOI：
10.1016/j.scitotenv.2021.150456
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发表时间：
2022
影响因子：
9.8
通讯作者：
Kessler, John D.
中科院分区：
文献类型：
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作者：
Joung, DongJoo;Ruppel, Carolyn;Southon, John;Kessler, John D.
通过对溶解在海水和淡水中的甲烷（14C-CH4）的天然放射性碳含量的测量，研究了甲烷的来源和动力学。然而，在沿着美国大西洋、太平洋和北冰洋边缘以及北美五大湖的调查中，一些样本显示14 C-CH 4值高度升高，比当代大气14 C-CH 4水平高出4 - 5倍。14CH4同位素的自然产生量太低，不足以引起这些观测结果，也不能解释位置和深度的变化。大量的实验室和现场验证测试和空白，以及显示这些升高值的相对少量的样本，都表明这些信号不是来自未知的程序问题。在这里，我们认为，核能发电的副产品包括本地排放的14CH4同位素到海洋和水生环境中，严重改变了测量的14C-CH4同位素信号。由于我们的几个采样点远离陆地核电站，我们进行了进一步的计算，得出的结论是，最高的异常in14 C-CH4可能源于排放的核动力船舶。
Measurements of the natural radiocarbon content of methane (14C-CH4) dissolved in seawater and freshwater have been used to investigate sources and dynamics of methane. However, during investigations along the Atlantic, Pacific, and Arctic Ocean Margins of the United States, as well as in the North American Great Lakes, some samples revealed highly elevated14C-CH4values, as much as 4–5 times above contemporary atmospheric14C-CH4levels. Natural production of the14CH4isotopologue is too low to cause these observations nor can it explain the variations in location and depth. Numerous lab and field validation tests and blanks, as well as the relatively small number of samples that display these elevated values, all suggest that these signals are not derived from an unknown procedural issue. Here we suggest that the byproducts of nuclear power generation include localized discharges of the14CH4isotopologue into marine and aquatic environments, severely altering the measured14C-CH4isotopic signals. Since several of our sample sites are distant from on-land nuclear powerplants, we conduct further calculations concluding that the most elevated anomalies in14C-CH4likely originate with discharge from nuclear-powered vessels.