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Recently it has been shown that there are two types of magnetite particles in the human brain, some, which occur naturally and are jagged in appearance, and others that arise from industrial sources, such as coal fired power plants, and are spherical. In order to confirm the latter, the magnetic component of coal ash is first purified and characterized by XRD, showing that it is magnetite with an average particle size of 211 nm. Studies confirm the coal ash magnetic behavior, and that the magnetite is not bound to the other components of coal ash but exist as an isolatable component. SEM studies confirm that in the process of burning coal at very high temperatures for industrial uses, the magnetite formed is spherically shaped, as recent studies of brain tissues of highly exposed urban residents have found. As such, the use of coal for industrial applications such as coking in the production of steel and in power plants is indicated to be a major source of the spherical magnetic combustion-associated magnetite fine particle and nanoparticle environmental pollution. The capacity of these magnetic particles to penetrate and damage the blood-brain-barrier and the early development of Alzheimer's disease hallmarks in exposed populations calls for detail analysis of magnetic fine and nanoparticle distribution across the world. Summation: Industrial coal usage produces spherical magnetic particles and nanoparticles, identical to those associated with neurological disorders., (Published by Elsevier Ltd.)

Using Artemia salina cysts (capsulated and decapsulated) and larvae (instar I, II and III) as experimental models, the potential effects of Fe 3 O 4 nanoparticles (Fe 3 O 4 -NPs) on marine ecosystems were investigated. Hatchability, mortality and a number of ethological, morphological and biochemical parameters were selected as end-points to define the toxic responses. Data showed that the hatching rates of capsulated and decapsulated cysts were significantly decreased (p < 0.01) following exposure to 600 mg/L for 24 and 36 h. The LC 50 values for instar II and III were 482 and 561 mg/L (could not be measured for instar I), and the EC 50 values for swimming inhibition of instar I, II and III were 474, 365 and 421 mg/L, respectively. Effects on hatchability, mortality and swimming were accounted for Fe 3 O 4 -NPs rather than iron ion released from the NPs. Instar II larvae showed the greatest sensitivity to Fe 3 O 4 -NPs, and followed by instar III, instar I, decapsulated cysts and capsulated cysts. Body lengths of instar I, II and III larvae were decreased in dose-dependent manners. Fe 3 O 4 -NPs attached onto the gills and body surface, resulting in irreversible damages. Reactive oxygen species, malondialdehyde content, total antioxidant capacity and antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) activities were substantially increased following exposure, indicating that toxic effects were related to oxidative stress. Mitochondrial malformation, cristae rupturing and membranous structure disruption were clearly observed after Fe 3 O 4 -NPs exposure. Fe 3 O 4 -NPs were ingested and well distributed in the gut, yolk and primary body cavity. Uptake kinetics data showed that the maximum Fe 3 O 4 -NPs content (16.4 mg/g) was reached at 30 h. The combined results so far indicate that Fe 3 O 4 -NPs have the potential to affect aquatic organisms when released into the marine ecosystems., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

A suite of rock magnetic experiments and intensive microscopic observations were carried out on Asian dust deposits in Seoul, Korea, collected on 19 and 23 March 2002, 9 April 2002 and 12 April 2003. Desert-sand and loess from the dust source regions in China were also analyzed as a comparison. Asian dust showed a higher magnetic concentration than the source region samples, indicating a significant influx of magnetic particles into Asian dust had occurred during its transportation. Electron microscopy identified carbon-bearing iron-oxides as the added material. These iron-oxides were likely to have been produced by anthropogenic pollution (fossil fuel combustion) while the wind-blown dusts passing across the industrial areas of eastern China and western Korea. Such wind-paths were confirmed by a simulation of the air-mass trajectories. The magnetic technique appears to be useful for determining the anthropogenic pollution of Asian dust.