Minerals and trace metals

Alexander FW, Clayton BE, Delves HT. 1974. Mineral and trace-metal balances in children receiving normal and synthetic diets. QJ Med 43 89-111. 

Intravenous requirements for energy, protein, amino acids, vitamins, minerals, and trace metals have not been definitely established for the newborn infant, although significant advances have been made in the past 5 years. Current estimates of intravenous requirements continue to be based on recommended oral intakes and a few nutrient balance studies. In this chapter, it is not possible to provide a detailed review on the termination of intravenous requirements for all the essential nutrients which are recommended for inclusion in TPN regimens. This topic has been the subject of several recent reviews (Jeejeebhoy, 1983 Heim et al, 1981 Zlotkin and Anderson, 1985 Winters et al, 1983). This section will deal with some of the newer issues associated with parenteral nutrition. 

As shown in Figure 14.4, each clay mineral exhibits a large range in the type and degree of isomorphic substitution. The central silicon atom in the tetrahedral layers can be replaced by aluminum, alkali, alkaline earth, and trace metal atoms. In the octahedral layers, the central Al and Mg atoms can be similarly replaced. The large range in composition within each mineral type reflects variability in the environmental conditions under which crystallization and chemical weathering occur. Thus, the... 

Water accounts for over half the body mass (55%) of the average human. Of the remaining 45%, 19% is protein, 19% is lipid, less than 1% is carbohydrate, and 7% is inorganic material. Nutrients must contain the raw materials that go into the construction of the components of the human body. In addition, nutrients must supply the necessary chemical energy and enzyme cofactors (vitamins and trace metal elements) that are required for the maintenance and growth of the human body. The human body requires nutrients such as water, amino acids, fats, carbohydrates, and major minerals in large amounts. Vitamins and trace metal elements are required in smaller amounts. 

Koelmans, A A., Gillissen, F. and Lijklema, L. (1996) Influence of salinity and mineralization on trace metal sorption to cyanobacteria in natural waters. Water Res., 30, 853-864. 

The pH was maintained at 5.0 by the addition of 2 M NaOH (Micro DCU-300 B. Braun Biotech). The fermentation temperature was 30°C and the stirrer speed was 500 rpm (MCU-200 B. Braun Biotech). Cell mass was produced in an initial batch phase using a glucose concentration of 64 g/L. The concentrations of mineral salts, trace metals, vitamins, and Ergosterol/ Tween-80 were the same as in the fed-batch experiments. When the glucose in the batch medium was completely consumed, 1.9 L of dilute-acid hydrolysate was pumped into the reactor at maximum pump speed, by using a peristaltic pump (Ul-M Alitea AB). The ratio between batch volume and the final volume (i.e., after all the hydrolysate had been added) was similar to the ratio in the PDU fed-batch experiments, approx 1 4. The reactor medium was sparged with nitrogen (600 mL/min). The C02 content in the exhaust gas was measured with a gas analyzer (TanDem Adaptive Biosystems, Luton, UK). 

Aqueous chemical speciation calculations (Alpers and Nordstrom, 1999 Bethke, 1996) have been used for some time to help understand the speciation of and trace metal chelation in diverse human body fluids such as plasma, wound fluids, saliva, sweat, fat emulsions, and gastrointestinal fluids (Taylor and Williams, 1995, 1998 Williams, 2000). In contrast, chemical speciation calculations have only been used infrequently in studies evaluating interactions between the human body and earth materials such as asbestos (Hume and Rimstidt, 1992 Gunter and Wood, 2000 Taunton et al., 2002 Davis et al., 1992, 1996). There are many potential uses of chemical speciation calculations in the interpretation of interactions between human body fluids and earth materials. For example, the interpretation of in vitro mineral solubility tests could be greatly improved by chemical speciation calculations on... 

The reaction by-products of sulfide oxidation are distinct thus, evidence of sulfide oxidation can be found in the chemical signatures of ground water. In aquifers where sulfide oxidation occurs, ground water chemistry should show a positive correlation of arsenic with sulfate, iron, and trace metals contained in the sulfide minerals. Increases in total dissolved solids and specific conductance also result from sulfide oxidation, due to an increase of dissolved ions in the impacted waters. Ground water impacted by sulfide oxidation may reveal a negative correlation of arsenic with pH, provided that there is minimal buffering capacity provided by the host rocks. 

Chloride minerals are rarely found in coal in the form of solid species because of high solubility of sodium, calcium and trace metal chlorides in coal strata waters. The "inherent" water content of coal is related to its porosity and thus the moisture content of lignite deposits can exceed 40 per cent decreasing to below 5 per cent in fully bituminous coals (11). Chlorides, chiefly associated with sodium and calcium constitute the bulk of water-soluble matter in British bituminous coals (12). Skipsey (13) has found that the distribution of chlorine coals was closely related to the salinity of mine waters. Hypersaline brines with concentrations of dissolved solids up to 200 kg m occur in several of the British Coalfields. 

The determination of distribution pattern of various forms of both macroelements and trace metals in soil profile is a very complicated task. We have to know the distribution of organic matter, mineral particle, and microbes, the existence of different barriers, redox conditions etc (Box 3)... 

Tailings Mineralogy. Tailings minerals consist of sand, clays, amorphous oxides, and trace metals. The sand is 97.5-99% Si02, 0.5-0.9% Al203, and 0.1-0.9% Fe (4, 27, 28). The oil sands, and hence the clay minerals found in the fine tails suspension, come from the McMurray Formation. The majority of clays in this formation are kaolinite and illite with traces of smectites, chlorite, vermiculite, and mixed-layer clays (5, 29). The upper McMurray Formation has a larger amount of smectites, whereas the lower McMurray Formation has larger amounts of vermiculite and mixed-layer clays. However, in both areas, kaolinite and illite are still the predominant clay minerals (5). 

The range of chemical analyses carried out to determine compliance with quality and specification requirements can include pH, titratable, and volatile acidity total solids, soluble solids (°Brix), water-in-soluble solids, sugars acid-insoluble ash, alkalinity of ash, mineral impurities, trace metals (tin, copper, zinc, iron, aluminum), heavy metals, e.g., lead ethanol preservatives such as sulfur dioxide, sorbic acid, benzoic acid, and benzoates. 

Reactions (1) and (4) result in strongly acidified solutions which, in addition to dissolve large amounts of Fe(II) and SO, also leach important quantities of many other major and trace metals from the mineralizations and the host rocks, including Al, Mg, and Ca (with minor Na, K, and Ba) from the accompanying aluminosilicates, carbonates, and sulfates, in addition to Cu, Zn, Mn, As, Pb, or Cd from other sulfides (sphalerite, chalcopy-rite, galena, arsenopyrite) and sulfosalts (tetrahedrite-tennantite). Iron and aluminum are usually the most abundant metal cations of those present in AMD [5, 9, 12, 22]. 

Milk is the most nutritionally complete food found in nature. All kinds of milk, human or animal, contain vitamins (principally thiamine, riboflavin, pantothenic acid, and vitamins A, B12, and D), minerals (caleimn, potassium, sodium, phosphoras, and trace metals), proteins (mostly easein), carbohydrates (principally lactose), and lipids (fats). However, the amounts of these nutrients present in different types of milk differ greatly. Cows milk and goats milk are almost identieal in every respect. Human milk contains less than half of the proteins and minerals of cows or goats milk, but almost 1.5 times as much sugar. Horses milk is quite low in proteins and fats compared with the others, whereas reindeer milk is very high in proteins, fats, and minerals, but quite low in carbohydrates. The average composition of whole cows milk is 87.1% water, 3.4% protein, 3.9% fats, 4.9% carbohydrates, and... 

Many analytical techniques have been applied to the determination of minerals and trace elements but the most successful are those based on atomic spectroscopy. The techniques included in the subsequent sections afford the sensitivity required to measure concentrations below 1 ppm in specimens of just a few pL or mg with almost total specificity and relatively few interferences. As situations of deficiency and toxicity are investigated, analytes may be present at very low or very high concentrations within the same specimen type. Therefore, techniques with differing sensitivities may be used, as appropriate, for the same application. Many biomedical investigations require the measurement of just one or two metals. Consequently, multi-element techniques are not necessarily as important as in some other application areas. Nevertheless, there are situations in which this facility does become important. 

It is clear then, that the differences in mineral accumulation exhibited by bacterial cells in the Rio Solimdes and the Rio Negro must reflect differences in the physical and chemical conditions of their riverine environments. The Rio Solimdes is a fertile river, rich in suspended sediments and dissolved inorganic solutes. As a result, the bacteria will have an abundant supply of metals in solution with which to complex and to accumulate. In contrast, the Rio Negro is an extremely infertile river characterized by low levels of major cations and trace metals. With very dilute waters, the bacteria presumably are unable to bind sufficient quantities of metals to form authigenic mineral phases, suggesting that both metal sorption and biomineralization largely reflect the availability of dissolved solutes in the water column. 

Medical Uses. Citric acid and citrate salts are used to buffer a wide range of pharmaceuticals at their optimum pH for stabiUty and effectiveness (65—74). Effervescent formulations use citric acid and bicarbonate to provide rapid dissolution of active ingredients and improve palatabiUty. Citrates are used to chelate trace metal ions, preventing degradation of ingredients. Citrates are used to prevent the coagulation of both human and animal blood in plasma and blood fractionation. Calcium and ferric ammonium citrates are used in mineral supplements. 

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