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Macrocyclic Receptors for Environmentally Sensitive Metal Ions
Published in Satish Kumar, Priya Ranjan Sahoo, Violet Rajeshwari Macwan, Jaspreet Kaur, Mukesh, Rachana Sahney, Macrocyclic Receptors for Environmental and Biosensing Applications, 2022
Satish Kumar, Priya Ranjan Sahoo, Violet Rajeshwari Macwan, Jaspreet Kaur, Mukesh, Rachana Sahney
The most notorious and prevalent toxic metal in the environment is mercury, present in elemental, inorganic and organic forms. It is a neurotoxin that can cause serious damage to the central nervous system, impairment of pulmonary and kidney function, heart diseases and brain dysfunction. Cadmium is used in pigments, fertilizers, Ni-Cd batteries and electroplating industries. Accumulation of cadmium in the kidney, lungs, and liver can lead to chronic effects on human health such as kidney dysfunction, reduced lung capacity, weak brittle bones and calcium metabolism disorders (Berhanu et al. 2019). Exposure to lead can cause damage to the central nervous system, kidney, liver, reproductive system and brain functions. It can lead to memory loss, dullness, irritability, insomnia, headaches, dizziness and mental retardation in children. Likewise, thallium is widely used in technological and industrial applications. It is extremely toxic because it acts like alkali metal ions in biological systems (Roper et al. 2008). Thallium can also be easily absorbed by the skin. It can cause adverse effects on the lungs, liver, heart, kidney and nervous system.
Soldering, brazing, and welding
Published in Andrew Livesey, Motorcycle Engineering, 2021
Silver solders are more malleable and ductile than brazing rods, and hence joints made with silver solder have a greater resistance to bending stresses, shocks, and vibration than those made with ordinary brazing alloys. As you can see this is very appropriate for bicycle frames. Silver solders are made in strip, wire (rod), or granular form and in a number of different grades of fusibility. The melting points vary between 630° and 800 °C according to the percentages of silver, copper, zinc, and cadmium they contain.
Status of Cadmium, Lead, and Selenium in the Soils of Selected African Countries and Perspectives of their Effects on Human and Environmental Health
Published in P.M. Huang, I.K. Iskandar, M. Chino, T.B. Goh, P.H. Hsu, D.W. Oscarson, L.M. Shuman, Soils and Groundwater Pollution and Remediation, 2020
Together with Zn and Hg, Cd, a metallic element, belongs to group IIb in the periodic table. Lead, Cu and to a greater extent Zn ores are the main sources of Cd. The ratio of cadmium to zinc is usually between 1:100 and 1:1000, depending on the source (Furkerson and Goetter, 1973). Cadmium is present in natural resources such as soils, water, and rocks as well as in petroleum and coal products. It is rarely found in a pure state. In the earth’s crust, Cd is distributed at an average concentration of 0.1 mg/kg.
Clarke concentrations of heavy metals in surface waters of the transboundary river Yertis (Kazakhstan)
Published in Water Science, 2023
Aizhan Ryskeldieva, Diana Burlibaeva, Almat Yerdesbay, Gulsara Kamelkhan, Nurbanu Sarova
More significant cadmium concentrations can be found in the time section (2010–2014) at the points (Ust-Kamenogorsk city and Predgornoe village). Figures 7–8 show the change of cadmium concentration over time. A gradual increase of cadmium concentration is observed (from Cc = 0.7 up to Cc = 3.8) between 2010 and 2013 at the Ust-Kamenogorsk point. The maximum value of the clarke concentration (Cc = 3.8) occurred in 2013. The cadmium content is not significant in 2014–2015. Consequently, after 2013, the site (Ust-Kamenogorsk city) shows a decline in cadmium concentration in the surface waters of the Yertis river (Cc = 0.005). At the observation point (Predgornoe village), no downward or upward trend is observed (Figure 8). The clarke concentration is distributed chaotically. High concentrations of clarkes were recorded in 2010 (Cc = 3.75) and 2013 (Cc = 4.415). Further, in 2014–2015 cadmium content was minimal (within Cc = 0.01–0.005) as at the point (Ust-Kamenogorsk city). A decline was observed. According to data from the National report (2019) of the Ministry of Ecology, Geology, and Natural Resources of the Republic of Kazakhstan, cadmium was not found in the surface waters of the Yertis river in 2019. Cadmium belongs to rare, dispersed elements: it is contained as an isomorphic mixture in many minerals and always in zinc minerals. Its main applications are in the manufacture of nickel-cadmium batteries, where cadmium salts are used. Cadmium is a by-product of zinc and is released into surface waters by this metal.
A facile-treated sago bark (Metroxylon sagu) as a biosorbent for Cd(II) ions removal in aqueous solution by using the batch method
Published in International Journal of Phytoremediation, 2023
Syiffa Fauzia, Hermansyah Aziz, Dahyunir Dahlan, Deliana Dahnum, Rahmiana Zein
Human activities discharge dangerous waste into the environment including heavy metals. Cadmium is a toxic metal released by industries such as electroplating, battery, plastic, paint, transportation, photography, alloys, electrical, rubber, oil-refining and so forth (Huang and Lin 2015; Sanusi et al.2015; García et al.2016). Heavy metal toxicity becomes a significant issue in heavy metals’ solubility and, reactivity, and neurological effect heavy metals. They can also accumulate in the body. The US Environmental Protection Agency (USEPA) has stated that the allowed amount of cadmium in drinking water is 0.003 mg/L. These heavy metals are responsible for diseases such as diarrhea, muscular cramps, nausea, and others (Chen et al.2015; Kumar et al.2016; Park et al.2017). Techniques such as ion exchange, phytoextraction, precipitation, reverse osmosis, and membrane separation have been utilized for heavy metals removal. However, these methods discharge the side product and the cost of operation is relatively high (Ahmad et al.2012; Lasheen et al.2012; Srinivas and Murthy 2016).
Restricted substances for textiles
Published in Textile Progress, 2022
Arun Kumar Patra, Siva Rama Kumar Pariti
Cadmium is a non-essential element to human biology but it is a highly-toxic element that emerges as a by-product of zinc production and is usually found as a contaminant in phosphate fertilizers. It is frequently used in numerous industrial processes. Cadmium is widely used in production of alloys, paints and pigments, electric cables, plastics and Ni-Cd batteries. Although its application in batteries has been considerable, its commercial use has declined in developed countries owing to environmental concerns. Cadmium is a transition element and together with mercury and lead, these are considered to be the ‘big three’ heavy metal poisons. For people occupationally exposed to cadmium, the entry of the toxic element is primarily through the respiratory system and secondarily by the gastrointestinal system and the skin. Non-occupational exposure also causes a variety of pathological changes in various organs and tissues. Cadmium has a broad carcinogenic activity affecting several organs like the pancreas, kidney, lungs, urinary tract, bladder and prostate. The EPA has therefore restricted the presence of cadmium to 5 parts per billion (ppb) in drinking water, the same as the limit set by the FDA (Food and Drug Administration) in the USA (Martin & Griswold, 2009).