1950年至2016年美国西北太平洋煤炭相关污染物的大气沉降

与煤有关的元素是有毒的和持久性的污染物，自从工业革命以来，主要是由点源排放在全球传播。华盛顿州生态部从华盛顿州东北部的深湖采集了一个沉积柱，以评估美国太平洋西北部最近的大气沉积变化。沉积柱被分为深度层段和210Pb测年。对每个截面的样品进行消化并使用ICP-MS进行金属和类金属的分析。数据显示最近砷、钡、硒和汞的浓度的增加。与1993年美国地质调查局怀俄明州弗雷蒙特冰川上部的冰芯数据、亚洲煤炭消耗数据和天气模式进行比较，表明向深湖沉积物输入的污染物是亚太地区燃煤活动的结果。最显著的是，自进行冰芯分析的1993年以来，深湖的汞沉积量从1996年的20 ppb增加到2014年的9470 ppb（增加了400倍）。

Atmospheric Deposition of Coal-Related Pollutants in the Pacific Northwest of the United States from 1950 to 2016

Coal related elements are toxic and persistent pollutants that has spread globally, mainly from point-source emissions, since the industrial revolution. A sediment core was collected from Deep Lake in north eastern Washington State by the Washington State Department of Ecology in order to assess recent changes in atmospheric deposition in the U.S. Pacific northwest. The core was divided into depth intervals and 210Pb-dated. A sample from each cross-section was digested and analyzed for toxic metals and metalloids using ICP-MS. Data show recent increases in the concentrations of arsenic, barium, selenium, and mercury. Comparison with a 1993 USGS ice core data from the Upper Fremont Glacier in Wyoming, Asian coal consumption data, and weather patterns suggests that pollutant inputs to Deep Lake sediments are the result of coal-burning activities in the Asia-Pacific region. Most notably mercury deposition in Deep Lake has increased from ~20 ppb in year 1996 to 9470 ppb in year 2014 (a ~400-fold increase), and since 1993 when the ice core was analyzed.