Department of Geological Sciences, University of Texas at El Paso, El Paso, Texas 79968, USA.
Environ Sci Technol. 2010 Mar 1;44(5):1544-50. doi: 10.1021/es902933y.
In this work, we use stable Zn and Cu isotopes to identify the sources and timing of the deposition of these metals in a sediment core from Lake Ballinger near Seattle, Washington, USA. The base of the Lake Ballinger core predates settlement in the region, while the upper sections record the effects of atmospheric emissions from a nearby smelter and rapid urbanization of the watershed. delta(66)Zn and delta(65)Cu varied by 0.50 per thousand and 0.29 per thousand, respectively, over the 500 year core record. Isotopic changes were correlated with the presmelter period ( approximately 1450 to 1900 with delta(66)Zn = +0.39 per thousand +/- 0.09 per thousand and delta(65)Cu = +0.77 per thousand +/- 0.06 per thousand), period of smelter operation (1900 to 1985 with delta(66)Zn = +0.14 +/- 0.06 per thousand and delta(65)Cu = +0.94 +/- 0.10 per thousand), and postsmelting/stable urban land use period (post 1985 with delta(66)Zn = 0.00 +/- 0.10 per thousand and delta(65)Cu = +0.82 per thousand +/- 0.12 per thousand). Rapid early urbanization during the post World War II era increased metal loading to the lake but did not significantly alter the delta(66)Zn and delta(65)Cu, suggesting that increased metal loads during this time were derived mainly from mobilization of historically contaminated soils. Urban sources of Cu and Zn were dominant since the smelter closed in the 1980s, and the delta(66)Zn measured in tire samples suggests tire wear is a likely source of Zn.
在这项工作中，我们使用稳定的锌和铜同位素来识别这些金属在来自美国华盛顿州西雅图附近的巴林格湖的沉积岩芯中的来源和沉积时间。巴林格湖岩芯的底部早于该地区的定居点，而上部则记录了附近冶炼厂的大气排放和流域快速城市化的影响。在 500 年的岩芯记录中，δ66Zn 和 δ65Cu 分别变化了 0.50‰和 0.29‰。同位素变化与前冶炼期（约 1450 年至 1900 年，δ66Zn=+0.39‰±0.09‰和 δ65Cu=+0.77‰±0.06‰）、冶炼厂运行期（1900 年至 1985 年，δ66Zn=+0.14‰±0.06‰和 δ65Cu=+0.94‰±0.10‰）和后冶炼/稳定城市土地利用期（1985 年后，δ66Zn=0.00‰±0.10‰和 δ65Cu=+0.82‰±0.12‰）相关。第二次世界大战后快速的早期城市化增加了金属负荷到湖中，但并没有显著改变 δ66Zn 和 δ65Cu，这表明这一时期增加的金属负荷主要来自历史上受污染土壤的活化。自 20 世纪 80 年代冶炼厂关闭以来，Cu 和 Zn 的城市来源一直占主导地位，而从轮胎样本中测量的 δ66Zn 表明轮胎磨损可能是 Zn 的一个来源。
