Abstract |
Throughout the history of the United States Lead (Pb) has been used in a wide range of domestic and industrial products such as gasoline, paint, smelting, glass making, and tire vulcanization. Although new inputs of Pb to soils ceased in the 1990s, legacy Pb continues to be a risk to human health, particularly children, through ingestion and/or inhalation of Pb-bearing particles. Current practices regarding the risk of exposure to soil Pb do not address and remediate high Pb exposure areas until exposure has occurred. This work aims to determine how Pb speciation and distribution relate to each other at the neighborhood-level in an urban environment. A total of 82 soil samples were collected in Akron, OH; 30 from the Summit Lake neighborhood (Fall 2018), and 52 from Akron Public School students residences (Summer 2019). Total Pb was measured by X-Ray Fluorescence (XRF) and potential bioaccessible Pb was determined using two methods: (1) a nitric acid solution and (2) a simulated gastric fluid. Extracted Pb was measured using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). Solid phase characterization will also be performed on samples to determine soil particle mineralogy and morphology through X-Ray Diffraction (XRD) and scanning electron microscopy (SEM). Total Pb values ranged from 34.6 mg/kg to 1969.6 mg/kg +/- 335.1, with an average value of 227 +/- 335.1 mg/kg. Bioaccessible Pb values for the nitric acid solution ranged from below the detectable limit (BDL) to 24.79 +/- 3.93 ppm, with an average of 2.50 +/- 3.93 ppm per sample. For Bioaccessible Pb from the simulated gastric fluid values ranged from BDL to 15.86 +/- 2.46 ppm, with an average value of 1.38 +/- 2.46 ppm. Total and Bioaccessible Pb values will be used to create, the first of its kind, neighborhood-level Pb speciation and distribution map for Akron, OH., which could aid in determining focus areas for remediation efforts.
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