Contrast enhancement agents and radiopharmaceuticals
A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha in Clark’s Procedures in Diagnostic Imaging: A System-Based Approach, 2020
An aerosol is a suspension of minute solid or liquid particles in a gas. In RNI, aerosols are principally used in lung ventilation studies, where they are most commonly produced by a jet nebuliser. The droplets produced are deposited on the lining of the airways during inhalation by the patient. The major factor influencing the site and extent of deposition is the droplet size; the optimum diameter of droplets is in the region of 0.5 mm. Larger droplets may be deposited in the upper respiratory tract, whereas smaller droplets may be exhaled. Other properties affecting deposition include the electrical charge on the particles, their ability to absorb moisture, the nature of the patient’s respiration and the state of the respiratory tract. Figure 2.22a demonstrates an aerosol-acquired image.
Dictionary
Mario P. Iturralde in Dictionary and Handbook of Nuclear Medicine and Clinical Imaging, 1990
A system of liquid or solid particles colloidally dispersed in a gas is called an aerosol. A system of solid substance or water-insoluble liquid colloidally dispersed in liquid water is called a hydrosol. There is no sharp line of demarcation between true solutions and colloidal systems, on the one hand, or between mere suspensions and colloidal systems on the other. When the particles of the dispersed phase are smaller than about 1 nm in diameter, the system begins to assume the properties of a true solution; when the particles dispersed are much greater than 1 μm, separation of the dispersed phase from the dispersing medium becomes so rapid that the system is best regarded as a suspension. Colloids such 99mTc-tin colloid are phagocyted by the reticuloendothelial system when given intravenously, allowing liver, spleen, and bone marrow imaging.
Hazards from Legionella *
Jamie Bartram, Rachel Baum, Peter A. Coclanis, David M. Gute, David Kay, Stéphanie McFadyen, Katherine Pond, William Robertson, Michael J. Rouse in Routledge Handbook of Water and Health, 2015
Epidemiological data suggest that Legionnaires’ disease from these types of systems is usually associated with direct exposure to the source. Spa pools and ‘hot tubs’ are common causes of disease from this category of systems. A range of different Legionella strains and species may cause infection (Fields et al., 2002). Clearly the contamination comes from the potable supply, but then enters a nutrient rich circulating environment with optimal growth temperatures. The aeration and circulation of heated water is conducive to the development of biofilms, growth of Legionella and protozoa and production of aerosol. In contrast to cooling towers, aerosol does not travel far from these devices. However, there is unavoidable direct exposure to aerosol of all individuals using or in close proximity to the spa pool. There exists the possibility of ingestion and aspiration as a source of infection from these devices (den Boer et al., 2002; WHO, 2007).
Nose-only inhalations of high-dose alumina nanoparticles/hydrogen chloride gas mixtures induce strong pulmonary pro-inflammatory response: a pilot study
Published in Inhalation Toxicology, 2021
Alexandra Bourgois, Dominique Saurat, Suzanne De Araujo, Alexandre Boyard, Nathalie Guitard, Sylvie Renault, Francisca Fargeau, Christine Frederic, Emmanuel Peyret, Emmanuel Flahaut, Aurélie Servonnet, Anne-Laure Favier, Ghislaine Lacroix, Sabine François, Samir Dekali
Combustion reactions from different sources can produce high volumes of complex aerosols containing various components as gases and particles in the environment (Sgro et al. 2012; Chivas-Joly et al. 2016). Solid composite propellants use in aerospace and defense fields lead to emission of complex combustion aerosols containing notably alumina (Al2O3) particles and hydrogen chloride gas (HClg) (Pellett et al. 1983; Meda et al. 2005). Indeed, high concentrations of Al2O3 particles and HClg were measured close to these propulsion systems under normal use conditions (classified data). Thermochemical simulations based on highly aluminized solid composite propellant (68% ammonium perchlorate and 20% aluminum) also confirm production of high quantities of Al2O3 particles and HClg during the combustion process (data not shown). Moreover, these pollutants can also be emitted, respectively, by industrial activities such as aluminum manufacturing (Pichard et al. 2005) and wastes incineration (Wang et al. 1999) increasing the risk of exposure to the workers.
Estimates of carbon nanotube deposition in the lung: improving quality and robustness
Published in Inhalation Toxicology, 2020
Matthew D. Wright, Alison J. Buckley, Rachel Smith
For inhalation studies bulk samples of carbon nanotubes can be aerosolized using a number of devices, including acoustic generators (McKinney et al. 2009), vortex shakers (Ku et al. 2013), dust mills, feeders or brush generators (Ma-Hock et al. 2009; Kasai et al. 2014), ultrasonic generators (Kim et al. 2017) and nebulizers or atomizers (Chortarea et al. 2015; Kadoya et al. 2016). The aerosol particles produced can be grouped into the same broad shape categories as indicated above but the nature of the aerosolization process, including the apparatus but also the environmental conditions e.g. humidity, may significantly affect the properties of the resulting aerosol (Ku et al. 2013; Ku and Kulkarni 2015; Pauluhn and Rosenbruch 2015; Ku and Birch 2019). The characteristics of the aerosol used for inhalation studies may therefore differ significantly from that which would be encountered in a workplace using the same material. This is an important factor to consider in the risk management process. In general, predicting the characteristics of airborne CNT particles from information on their bulk material properties (Jackson et al. 2015; Poulsen et al. 2017) is not straightforward (see Supplementary Information for further discussion).
Monitoring of polycyclic aromatic hydrocarbons (PAHs) in smoke of charcoal grilled meat-restaurants in Amman, Jordan
Published in Toxin Reviews, 2022
Sharif H. Arar, Sarya G. Ikbarieh, Mohammed H. Kailani, Mahmoud A. Alawi
Air pollution is one of the most common and important issues in the last decades which is associated with environmental and human health issues as a result of the release of harmful substances into the air. It emerged and grew in the industrial and developing countries due to the industrial activities for many reasons such as economic growth, urbanization, consumption of energy, transportation, and the fast population growth (Chen and Kan 2008). Air pollution affects the ecosystem and is released from hundreds of different sources classified as human (anthropogenic) and natural sources (Ghorani et al.2016). There are many sources of human activities that lead to air pollution. The most important ones are electric power plants, factories, and vehicle emissions (Aschner and Costa 2015). Combustion of carbon as coal, fuel oil, wood, and natural gas, agricultural emissions, residential heating and cooking re-emission from terrestrial and aquatic surfaces, wars, nuclear tests, and from using chemicals are also other human-made sources (Morand and Maesano 2004, Hewitt and Jackson 2007). On the other hand, natural sources such as forests fires, volcanic activities, dust storms that can be a source of pollutants by emitting the aerosol into the atmosphere are causing air pollution (Vallero 2007).
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