University of Washington Tacoma, Environmental Science and Studies, Interdisciplinary Arts and Sciences Program, 1900 Commerce St., Box 358436, Tacoma, WA 98402, USA.
Bellarmine Preparatory School, 2300S Washington St., Tacoma, WA 98405-1399, USA.
Sci Total Environ. 2014 Feb 15;472:530-7. doi: 10.1016/j.scitotenv.2013.11.004. Epub 2013 Dec 6.
The American Smelting and Refining Company (ASARCO) smelter in Ruston, Washington, contaminated the south-central Puget Sound region with heavy metals, including arsenic and lead. Arsenic and lead distribution in surface sediments of 26 lakes is significantly correlated with atmospheric model predictions of contaminant deposition spatially, with concentrations reaching 208 mg/kg As and 1,375 mg/kg Pb. The temporal distribution of these metals in sediment cores is consistent with the years of operation of the ASARCO smelter. In several lakes arsenic and lead levels are highest at the surface, suggesting ongoing inputs or redistribution of contaminants. Moreover, this study finds that arsenic is highly mobile in these urban lakes, with maximum dissolved arsenic concentrations proportional to surface sediment levels and reaching almost 90 μg/L As. With 83% of the lakes in the deposition zone having surface sediments exceeding published "probable effects concentrations" for arsenic and lead, this study provides evidence for possible ongoing environmental health concerns.
美国冶炼和精炼公司（ASARCO）在华盛顿州拉斯特的冶炼厂造成了包括砷和铅在内的重金属污染南中普吉特海湾地区。26 个湖泊的表层沉积物中砷和铅的分布与大气污染物沉降模型的空间预测显著相关，浓度分别达到 208 毫克/千克砷和 1375 毫克/千克铅。这些金属在沉积物核心中的时间分布与 ASARCO 冶炼厂的运营年限一致。在几个湖泊中，砷和铅的含量在表层最高，表明仍在持续输入或重新分布污染物。此外，本研究发现，砷在这些城市湖泊中具有很强的迁移性，最大溶解砷浓度与表层沉积物水平成正比，达到近 90μg/L 砷。由于沉积区 83%的湖泊表层沉积物超过了砷和铅的“可能影响浓度”，本研究为可能持续存在的环境健康问题提供了证据。
