Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6329323 | Science of The Total Environment | 2014 | 10 Pages |
Abstract
The solubility of soil-associated potentially toxic elements (PTEs) in surrogate biological fluids provides valuable information about their potential health hazard. This work addresses the concentrations and bioaccessibility of nine PTEs (As, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn) in thirty eight agricultural land and playground soils collected from a semi-arid urban area of Baghdad-Iraq. Two surrogate biological fluids (SBFs), macrophage vacuole (MS) and gastric (GS) solutions, were used to extract the metals to simulate the biological availability of the PTEs via inhalation and ingestion exposure routes. ICP/AES was used to quantify PTEs in both strong acid digests (for total concentration), and in the SBF extracts. Soil contamination factors showed that some sites exhibited elevated levels of As (36 ± 10 mg/kg), however, these levels of As are not likely to have significant human health impacts whether the particulate arsenic is ingested or/and inhaled. Soil-geochemical variables (including: pH, EC, CO3=, soil organic carbon (SOC)) and major elements (e.g. Al, Ca, and Fe) were used to interpret the lability of PTEs in the soils. Hazardous index (HI) based non-cancer risk of inhalation and ingestion of PTEs was estimated to be 2-fold higher for that based on total element concentrations compared with that for bioavailable fractions for both children and adults. A similar conclusion was reached for the estimated cancer risk (which was lower than the threshold level of concern for children and adults). A sensitivity analysis showed that there is a 97% chance for children and 90% for adults to have hazardous indices of the total PTEs > 1 (the acceptable value); the corresponding metrics for the bioavailable fraction of the elements were 39% for children, and 3% for adults; these results were sensitive to the concentrations of “airborne” soil particles.
Keywords
SBFICP/AESPTESMRLMDLMCsHEPASRMEPAADIPCAThermal analysisIAEAEnvironmental Protection AgencyPrincipal component analysisMinimal risk levelCancer riskhigh efficiency particulate airMonte Carlo SimulationGISGPSGeographic information systemSOCContamination factorPotentially toxic elementsenrichment factorBioavailabilityCorrelation matrixMethod Detection Limitstandard reference materialAverage daily intakeelectric conductivitySoil organic carbon
Related Topics
Life Sciences
Environmental Science
Environmental Chemistry
Authors
Samera H. Hamad, James J. Schauer, Martin M. Shafer, Esam Abd Al-Rheem, Pamela S. Skaar, Jongbae Heo, Isabel Tejedor-Tejedor,