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Contribution of Bioavailable Silicon in Human Health
Published in Debasis Bagchi, Manashi Bagchi, Metal Toxicology Handbook, 2020
Numerous studies have reported the effects of environmental exposure to silicon and its many chemical forms and the resultant detrimental effects on humans. Primarily inhaled crystalline silica and silica-derived asbestos are well-recognized carcinogens.11 In fact, silicon has long been recognized as a pulmonary carcinogen with resultant silicosis or asbestosis developing upon prolonged and/or heavy exposure to airborne material.12 As a disease of the lungs, silicosis is caused by chronic inhalation of mineral dust and is characterized by progressive fibrosis (excessive fibrous connective tissue) and chronic shortness of breath.13 Asbestosis is similar in etiology and pathology but distinct as an exposure. There are clearly inherent dangers associated with inhalation of crystalline silica; however, there are multiple forms of silica in nature that are considered safe, absorbable, and potentially beneficial to human health.14 Regarding non-toxic forms, questions remain as to the relative water solubility of different compounds, overall amounts of each ingested, efficiency of absorption and overall bioavailability (delivery to target tissues). Low-molecular-weight silica can dissolve in water as silicic acid rendering it bioavailable and potentially beneficial in humans. Collectively, the lack of understanding of the relative dependence of physicochemical structure of silica and silicates on water solubility for absorption and safety has limited research progress regarding silicic acid. Thus, a better understanding of the chemistry of silica, specifically of aqueous OSA, is critical to initiating, executing, and corroborating research on potential health benefits.
Measurement of number and mass size distributions of light-absorbing iron oxide aerosols in liquid water with a modified single-particle soot photometer
Published in Aerosol Science and Technology, 2022
Tatsuhiro Mori, Yutaka Kondo, Kumiko Goto-Azuma, Nobuhiro Moteki, Atsushi Yoshida, Kaori Fukuda, Yoshimi Ogawa-Tsukagawa, Sho Ohata, Makoto Koike
FeOx particles are emitted both from anthropogenic and natural sources. Anthropogenic sources are mainly blast furnaces of iron manufacturing facilities, coal and heavy oil combustion, and the brakes of motor vehicles (Fu et al. 2012; Machemer 2004; Sanderson et al. 2016). Natural sources include emissions of mineral dust particles from desert soils (Nowak et al. 2018). Emitted FeOx particles would become hydrophilic while aging during transport; therefore, it is likely that FeOx-containing particles with diameters of less than a few micrometers are removed from the atmosphere mainly by precipitation. To improve our understanding of the wet deposition of FeOx, accurate measurements of the number and mass size distributions of FeOx in hydrometeor samples are needed.
Evaluation of atmospheric dust deposition rates and their mineral characterization in copper and iron mining areas, Singhbhum, India
Published in Journal of the Air & Waste Management Association, 2020
Mukesh Kumar Mahato, Abhay Kumar Singh
Atmospheric air is necessary for humans and other living beings to exist. Major sources of air pollution can be broadly categorized into both anthropogenic and natural emissions. Natural emissions are not yet under human control, however technologies are available for mitigating air pollution through human emissions. Industries (e.g., thermal power plants, refineries, steel plants, open cast mines, bricks kiln) and vehicle and household emissions are the largest anthropogenic sources of air pollution. Mining is a significant source of emissions from dust among the numerous sources of air pollution (Ghose and Majee 2000). Factors such as vegetation cover, precipitation, wind strength, and soil moisture regulate the amount of dust in the air (Ta et al. 2004). Dust consists primarily of loose particles, which are caused by soil erosion, road transport, manufacturing, volcanic eruptions, and so on. Atmospheric mineral dust plays a key role in controlling various atmospheric processes such as cloud dynamics, precipitation, and atmospheric chemistry (Andreae and Crutzen 1997; Kulshrestha et al. 2009). Mineral dust has a major effect on biodiversity and climate and biogeochemical cycles by depositing minerals and organic materials into the terrestrial ecosystem (Jickells, An, and Andersen 2005; Lawrence and Neff 2009).
Gamma ray characterization of the albedo of atmospheric dust from Southeast Anatolia, Turkey
Published in Instrumentation Science & Technology, 2021
Tuba Rastgeldi Dogan, Demet Yilmaz, Serife Yalcin
Mineral dust contributes to the aerosol load in the atmosphere which has significant effects on air quality, climate, atmospheric chemistry, and the biosphere. The soil is primarily mobilized by wind in arid areas and may be transported over long distances in substantial quantities.[1] Airborne fine dust (<2.5 μm diameter) poses risks for the respiratory system and adversely impacts visibility. Scattering and absorption by dust impact the Earth's radiation distribution, the troposphere’s thermal formation, and actinic fluxes, leading to changes in dynamical and photochemical systems. Microphysical properties may be altered by the coating of dust under polluted conditions.[2]