Cadmium mobility

Salt D.S., Prince R.C., Pickering I.J., Raskin I. Mechanisms of cadmium mobility and accumulation in Indian mustard. Plant Physiol 1995 109 1427-1433. 

Shenker M., Fan T.W.M., Crowley D.E. Phytosiderophores influence on cadmium mobilization and uptake by wheat and barley plants. J Environ Qual 2001 30 2091-2098. 

There are also natural geochemical anomalies where soils are enriched by cadmium, for example, in the central parts of Sweden. Here the cultivation of crops accumulating cadmium (grains, potato, some grasses) is not recommended. In the coastal marine areas the cadmium mobility in soils is stimulated by its complexation with chlorine. 

Lamy, I., Bourgeois, S., and Bermond, A., Soil cadmium mobility as a consequence of sewage sludge disposal, J. Environ. Qual., 22, 731, 1993. 

Jones, M.M., Singh, P.K, Gale, G.R, Smith, A.B, Atkins, L.M. (1992). Cadmium mobilization in vivo by intraperitoneal or oral administration of monoalkyl esters of meso 2,3-dimer-captosuccinic acid. Pharmacol. Toxicol. 70 336-43. 

Field evidence for changing cadmium mobilities was reported by Holmes et al. 

Because of the increasing emphasis on monitoring of environmental cadmium the detemiination of extremely low concentrations of cadmium ion has been developed. Table 2 Hsts the most prevalent analytical techniques and the detection limits. In general, for soluble cadmium species, atomic absorption is the method of choice for detection of very low concentrations. Mobile prompt gamma in vivo activation analysis has been developed for the nondestmctive sampling of cadmium in biological samples (18). 

The most common toxic metals in industrial use are cadmium, chromium, lead, silver, and mercury less commonly used are arsenic, selenium (both metalloids), and barium. Cadmium, a metal commonly used in alloys and myriads of other industrial uses, is fairly mobile in the environment and is responsible for many maladies including renal failure and a degenerative bone disease called "ITA ITA" disease. Chromium, most often found in plating wastes, is also environmentally mobile and is most toxic in the Cr valence state. Lead has been historically used as a component of an antiknock compound in gasoline and, along with chromium (as lead chromate), in paint and pigments. 

M. Mench and E. Martin, Mobilization of cadmium and other metals from two soils by root exudates of Zea mays L., Nicotiana tabacum L. and Nicotiana rustica L. Plant Soil I32 %1 (1991). 

The CBD CdS was also applied in other areas of device fabrication and application. Mereu et al.32 fabricated thin-film field-effect transistors using CBD CdS on Si02/Si (n-type) substrates. Meth et al.33 fabricated thin-film transistors (TFTs) that incorporated patterned CBD cadmium sulfide as the active layer. Mobility in the =1 -cm2/Vs range with on/off ratios of =105 are needed for practical TFTs (e.g., for displays). Mobility values of 0.1 -1 cm2/Vs with on/off ratios exceeding 107 have been reported for these types of TFTs using CBD CdS. 

Ethambutol Hydrochloride (+)-2-Amino- Butan-l-ol TLC-Method Adsorbent-Silica Gel-G, Mobile Phase-Ethyl acetate Glacial acetic Acid HC1 H20(11 7 1 1) Apply 2pi of each of two solns. in MeOH, containing (1) 5% w/v of T.S. (2)0.050% w/v of (+)-2-aminobutan-l-ol. Remove TLC plates, dry in air, heat at 105°C for 5 mts, cool, spray with cadmium and Ninhydrin soln.2, heat to 90°C for 5 mts. The spot obtained with (2) is more intense than with (1). NMT 1.0... 

Mid-depth maxima are produced by mid-depth sources of metals. Some of these maxima are created by remineralization of detrital biogenic particles, such as seen in Figure 11.4f for cadmium. Others are caused by lateral transport of metals mobilized from coastal sediments as illustrated in Figure 11.17(a) for manganese. Mid-depth maxima can also result from hydrothermal emissions as shown in Figure 11.19 for Mn (aq) and He(g) at a site in the Eastern North Pacific Ocean. Hydrothermal fluids are emitted into the ocean from chimneys located atop the East Pacific Rise at water depths of about 2500 m. After entering the ocean, the Mn and He are entrained in subsurfece currents and... 

Like Zn, Cd is a Group IIB element and occurs in soils exclusively in the +2 oxidation state as the Cd + cation. Cadmium and zinc are often co-precipitated with each other in sulfide minerals in rocks (p/fCdS = 27.0). Hence Cd tends to be highly immobile under anaerobic sulfate-reducing conditions, but under acid, oxidizing conditions it is released in soluble and mobile forms. Hence soils... 

Cadmium is found naturally deep in the subsurface in zinc, lead, and copper ores, in coal, shales, and other fossil fuels it also is released during volcanic activity. These deposits can serve as sources to ground and surface waters, especially when in contact with soft, acidic waters. Chloride, nitrate, and sulfate salts of cadmium are soluble, and sorption to soils is pH-dependent (increasing with alkalinity). Cadmium found in association with carbonate minerals, precipitated as stable solid compounds, or coprecipitated with hydrous iron oxides is less likely to be mobilized by resuspension of sediments or biological activity. Cadmium absorbed to mineral surfaces (e.g., clay) or organic materials is more easily bioaccumulated or released in a dissolved state when sediments are disturbed, such as during flooding. 

Tyler LD, McBride MB. 1982. Mobility and extractability of cadmium, copper, nickel, and zinc in organic and mineral soil columns. Soil Science, 134 198-205. 

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