School of the Environment, University of Toronto, Toronto, Canada.
Institute of Atmospheric and Environmental Sciences, Department of Environmental Analytical Chemistry, J.W. Goethe-University, Frankfurt am Main, Germany.
Sci Total Environ. 2015 Dec 15;538:564-72. doi: 10.1016/j.scitotenv.2015.08.085. Epub 2015 Aug 28.
This study aims to examine the elemental enrichment patterns in low to medium traffic areas over a three year period in Toronto, Canada. Soils were sampled at three locations with different volumes of traffic between 2010 and 2013. A range of elements, including V, Cr, Mn, Cu, Cd, As, Sb and Pb, were measured in acid digested samples using ICP-MS. While the concentrations of Cd, Sb and Pb were found to be relatively low, a significant, albeit small increase in their levels over time was determined for all sites. For the low traffic areas, median Cd, Sb and Pb concentrations increased from 0.18mg Cd/kg, 0.14mg Sb/kg and 12mg Pb/kg in 2010 to 0.38mg Cd/kg, 0.21mg Sb/kg and 15mg Pb/kg in 2012, respectively. For the medium traffic site, the respective levels of Cd and Sb rose from 0.19mg Cd/kg and 0.14mg Sb/kg in 2010 to 0.49mg Cd/kg and 0.28mg Sb/kg in 2012. Median Pb concentrations at the medium traffic site were comparable to those at the low traffic sites (13mg/kg in 2010 and 15mg/kg in 2012). Principal Component Analysis (PCA) revealed the existence of two components (rotated), which explained 77% of the variance for all sites: 1. PC1 with large loadings of V, Cr, Co and Cu that likely originate from the commercial soil originally used for monitoring purposes, and 2. PC2 with high correlations between Cd, Sb and Pb, attributed to traffic sources of emissions. The resuspension and transport of more mobile fractions of contaminated dust and soil particles is hypothesized to be contributing to an elemental enrichment of soils located in low traffic areas.
本研究旨在考察加拿大多伦多低至中等交通量地区三年内的元素富集模式。2010 年至 2013 年，在三个交通量不同的地点采集土壤样本。使用 ICP-MS 对酸消解后的样品进行了一系列元素（包括 V、Cr、Mn、Cu、Cd、As、Sb 和 Pb）的测量。尽管 Cd、Sb 和 Pb 的浓度相对较低，但所有地点的水平均随着时间的推移呈显著（尽管较小）上升趋势。对于低交通区，Cd、Sb 和 Pb 的中位数浓度从 2010 年的 0.18mg Cd/kg、0.14mg Sb/kg 和 12mg Pb/kg 分别增加到 2012 年的 0.38mg Cd/kg、0.21mg Sb/kg 和 15mg Pb/kg。对于中等交通量地点，Cd 和 Sb 的相应水平从 2010 年的 0.19mg Cd/kg 和 0.14mg Sb/kg 上升到 2012 年的 0.49mg Cd/kg 和 0.28mg Sb/kg。中等交通量地点的 Pb 中位数浓度与低交通量地点相当（2010 年为 13mg/kg，2012 年为 15mg/kg）。主成分分析（PCA）揭示了两个成分（旋转）的存在，它们解释了所有地点 77%的方差：1. PC1，具有大量 V、Cr、Co 和 Cu 的负荷，可能来自最初用于监测目的的商业土壤；2. PC2，Cd、Sb 和 Pb 之间具有高度相关性，归因于交通排放源。推测受污染灰尘和土壤颗粒更易移动的部分的再悬浮和传输导致低交通量地区土壤的元素富集。
