Metal bioaccessibility, particle size distribution and polydispersity of playground dust in synthetic lysosomal fluids
Autor: | A. L. Gallego-Hernández, Efrén Pérez-Segura, Mercedes Meza-Montenegro, Francisco Maldonado-Escalante, Francisco Martín Romero, Ernesto Hernández-Mendiola, Mónica Acosta-Elías, Leticia García-Rico, Martín Pedroza-Montero, Sofía Navarro-Espinoza, M. Barboza-Flores, Karla Santacruz-Gómez, Diana Meza-Figueroa, Belem González-Grijalva |
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Rok vydání: | 2020 |
Předmět: |
Environmental Engineering
010504 meteorology & atmospheric sciences Chemistry Dispersity chemistry.chemical_element Dust Zinc 010501 environmental sciences 01 natural sciences Pollution Copper Dynamic light scattering Metals Particle-size distribution Environmental Chemistry Particle Particle size Cities Particle Size Lysosomes Waste Management and Disposal Arsenic 0105 earth and related environmental sciences Nuclear chemistry |
Zdroj: | Science of The Total Environment. 713:136481 |
ISSN: | 0048-9697 |
Popis: | Inhalation of playground dust-derived fine particles in schoolyards poses a risk from exposure to metal(oids) and minerals. In this work, we obtained the total concentration and bioaccessibility of metal(oids) with Gamble Solution (GS) and Artificial Lysosomal Fluid (ALF) synthetic solutions, simulating the extracellular neutral pH environment of the lung and the intracellular conditions of the macrophage, respectively. Scanning Electron Microscope (SEM), and Dynamic Light Scattering analysis (DLS) techniques were used to characterize particles with a size smaller than 2.5 μm, which can be assimilated by macrophages in the deep part of the lung. Arsenic (As), lead (Pb), copper (Cu), manganese (Mn), zinc (Zn), and iron (Fe) showed concentrations of 39.9, 147.9, 286, 1369, 2313, 112,457 mg·kg−1, respectively. The results indicated that all studied elements were enriched when compared to (i) local geochemical background and (ii) findings reported in other cities around the world. Bioaccessibility of metal(oids) in GS was low-moderate for most studied elements. However, in ALF assays, bioaccessibility was high among the samples: for lead (Pb = 34–100%), arsenic (As = 14.7–100%), copper (Cu = 17.9–100%), and zinc (Zn = 35–52%) possibly related to hydrophobic minerals in dust. SEM and DLS image analysis showed that playground dust particles smaller than 2.5 μm are dominant, particularly particles with a size range of 500–600 nm. The polydispersity detected in these particle sizes showed that most of them might be crystalline compounds (elongated shapes) forming agglomerates instead of combustion particles (spheres). Moreover, the circularity detected varies from 0.57 to 0.79 (low roundness), which corroborates this finding. The presence of agglomerates of ultrafine/nanoparticles containing highly bioaccessible metals in playground sites may have severe implications in children's health. Therefore, further studies are required to characterize the size distribution, structure, shape and composition of such minerals which are essential factors related to the toxicology of inhaled dust particles. |
Databáze: | OpenAIRE |
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