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Abstract The distribution of legacy heavy metals in industrial city soils is not well documented. Therefore, fundamental details such as the ‘background’ (i.e., non-road/non-dripline) concentration of trace metals in urban soils are uncertain. While there has been a strong focus on mapping lead contamination near roads and residences, these studies are generally not placed in the context of the urban background. In this study, ‘background’ distributions of urban relevant trace metals: arsenic, cadmium, copper, lead, and zinc were mapped based on soil samples collected throughout Pittsburgh. Distinct spatial patterns were revealed: contamination is elevated in the eastern portion of the study area, driven by dominant wind patterns and historical coking activities in low-lying areas (paleochannels), areas subject to atmospheric temperature inversions that focus air contamination. The mixing analysis revealed spatial structures in contributions of industrial activities to metal soil contamination. In particular, regions enriched in cadmium relative to zinc (i.e., Zn:Cd<317) were located near historical coking operations, and areas enriched in lead relative to zinc (Pb:Zn>1) were located in areas with historical secondary lead smelters. These results suggest a comprehensive accounting of the trace metals concentrations in background soils has important implications for the assessment of exposure risk in populations residing in historically industrial areas. Relatively sparse sampling of background conditions in urban systems can indicate patterns of legacy contamination and attribute this contamination to historical sources.
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This content will become publicly available on December 12, 2025
Distribution of Metals and Surface Sediment Texture in Long Island Sound
The Long Island Sound (LIS), located between Connecticut and Long Island, New York, is a crucial estuarine ecosystem that is affected by human activities in the surrounding areas. This study uses sediment grab samples from central Long Island Sound that have been collected as part of a larger habitat mapping effort in collaboration with several research groups including the Lamont-Doherty Earth Observatory of Columbia University. We determine element, and especially metal content of the sediment grab samples using x-ray fluorescence (XRF), and map their distribution in the study area, which is essential for characterizing the LIS sediment environment. By comparing the current metal contamination data with historical records, and grain size information we seek to uncover environmental changes over time. The analysis reveals an increase in metal concentrations from east to west, particularly in finegrained sediments. Historical industrial activities significantly contribute to elevated metal levels, with higher concentrations of copper and zinc observed due to restricted water circulation and industrial runoff. Other factors such as weather, human activity and ocean currents probably also influenced the detailed metal distribution.
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- Award ID(s):
- 2349621
- PAR ID:
- 10572308
- Publisher / Repository:
- American Geophysical Union
- Date Published:
- Format(s):
- Medium: X
- Location:
- Washington, D.C.
- Sponsoring Org:
- National Science Foundation
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