Aluminium exposure

Aluminium is an environmentally abundant element and has no known biological function in living cells. On the other hand, A1 exhibits biological toxicity as demonstrated in experimental models." " Intake and output of aluminium for the healthy population from various sources, biological monitoring of occupational aluminium exposure in serum and speciation analysis of the amount and composition of A1 species with high and low molecular masses, have been reviewed by several groups. Besides the use of mass spectrometric and non-mass spectrometric techniques (e.g., ETAAS after separation of human serum proteins ) ESI-MS-MS analysis has also been performed to identify the A1 species. 

An identical condition can occur in aluminium plant workers and miners, and can be reproduced in animal experiments. However, some clinically similar encephalopathies do occur spontaneously (or possibly as a result of uremia) in children where no link with aluminium exposure can be found. 

Muller M, Anke M, Illing-Gunther H (1997) Oral aluminium exposure of adults in Germany -A long-term survey. In Fischer PWF et al. eds. Trace Flements in Man and Animals - 9, pp. 177-178. NRG Research Press, Ottawa, Canada. 

RSD of 40-60% at 1 /poor performance. Methodology of itself does not seem to be a key factor, since most laboratories have been using similar methodology based on graphite furnace atomic absorption spectrometry. The most important factor appears to be the experience of the laboratory carrying out the analysis. For some schemes, there has been a dramatic rise in the number of participants, mostly of laboratories with very little previous experience of trace element analysis (Taylor, 1990). With the exception of a number of experienced laboratories, the performance of a large number of laboratories is insufficient to allow a proper assessment of aluminium exposure (Taylor, 1990). The performance of laboratories has also been impeded by the lack of suitable reference materials, particularly in the case of water and dialysis fluid. 

The actual aluminium contents in 40 neonatal parenteral nutrition solutions and 16 component products used in parenteral nutrition formulations have been determined and compared with the calculated amounts from manufacturers product labels, and ascertain whether the actual aluminium exposure exceeds the FDA recommended maximum [14 ]. The measured and calculated aluminium concentrations exceeded the FDA recommended safe... 

Drug formulations Aluminium can contaminate solutions used in parenteral nutrition. The FDA has mandated product labelling of the components of parenteral nutrition and has recommended a maximum aluminium exposure of 5 micrograms/kg/day. 

A worm called C. elegans that is grown in high levels of +3 aluminum. .. K. E. Page et al. Aluminium exposure disrupts elemental homeostasis in Caenorhabditis elegansP 2012. Metallomics 4, p. 512. DOl 10.1039/c2mt00146b. 

Aluminium toxicity has been studied retrospectively in 36 hospitalized adults who had a serum creatinine concentration at least 1.5 times greater than on the first day of parenteral nutrition 12 were undergoing hemodialysis [8 ]. Mean aluminium exposure was 3.8 pg/kg/day in the 36 patients, of whom 29 had safe calculated exposures (5 pg/kg/day) and also significantly higher serum creatinine concentrations than those with high aluminium exposure. The authors suggested that most patients with acute kidney disease who require parenteral nutrition do not receive excessive exposure to aluminium. 

Cardiovascular Chronic aluminium exposure associated with cardiotoxic manifestations is rather rarely reported. A recent case study reported Mobitz type I second-degree atrioventricular block and nonsustained ventricular tachycardia (VT) following chronic occupational aluminium exposure [4 ]. 

Aluminium is the most widely used element in our daily lives. Some of the sources of aluminium include drinking water, food additives and cooking utensils made of aluminium. High amoxmts of aluminium have been reported to be mixed with mashed tomatoes and yogurt during processing from normal and noncoated aluminium pans as a result of acidity. Aluminium is not essential for life processes, but increased amounts have been linked to various disorders such as microcytic anaemia, bone disturbances, neurodegenerative disorders such as Alzheimer s disease (AD) and Parkinson s disease, amyotrophic lateral sclerosis and encephalopathy. Smaller studies have demonstrated that aluminium exposure is associated with the impairment of mitochondrial function in vitro. 

The yield of iso-propylbenzene is influenced considerably by the quality of the anhydrous aluminium chloride employed. It Is recommended that a good grade of technical material be purchase in small bottles containing not more than 100 g. each undue exposure to the atmosphere, which results in some hydrolysis, is thus avoided. Sealed bottles containing the reagent sometimes have a high internal pressure they should be wrapped in a dry cloth and opened with care. 

Aluminium is an extremely light, white metal and whilst hard is malleable and duetile. On exposure to air the metal forms a proteetive oxide film whieh reduees its reaetivity. Its eompounds tend to be eovalent in nature die sulphate is hydrolysed in solution and die triehloride is volatile. 

The only reports of directed synthesis of coordination complexes in ionic liquids are from oxo-exchange chemistry. Exposure of chloroaluminate ionic liquids to water results in the formation of a variety of aluminium oxo- and hydroxo-contain-ing species [4]. Dissolution of metals more oxophilic than aluminium will generate metal oxohalide species. FFussey et al. have used phosgene (COCI2) to deoxochlori-nate [NbOa5] - (Scheme 6.1-1) [5]. 

Filiform corrosion is characterised by the formation of a network of threadlike filaments of corrosion products on the surface of a metal coated with a transparent lacquer or a paint him, as a result of exposure to a humid atmosphere. This phenomenon first attracted attention because of its formation on lacquered steel, and for this reason it is sometimes referred to as underfilm corrosion, but although it is most readily observed under a transparent lacquer it can also occur under an opaque paint film or on a bare metal surface. Filiform corrosion has been observed on steel, zinc, magnesium and aluminium coated with lacquers and paints, and with aluminium foil coated with paper. Surface treatment of the metal by phosphating or chromating lessens the tendency for filiform corrosion to occur, but it is not completely... 

The effect of exposure time on the corrosion of copper and aluminium is illustrated in Table 2.17. The results quoted by Southwell, Hummer and... 

The embrittlement caused to aluminium alloys by pre-exposure to moist atmospheres or stress-corrosion environments is thought to be due to hydrogen in the atomic form. Intergranular bubbles of hydrogen, formed in association with certain precipitates, have been observed by HV and... 

In addition to examining pre-exposure effects, the slow strain-rate testing technique has been used increasingly to examine and compare the stress-corrosion susceptibility of aluminium alloys of various compositions, heat treatments and forms. A recent extensive review draws attention to differences in response to the various groups of commonly employed alloys which are summarised in Fig. 8.57. The most effective test environment was found to be 3 Vo NaCl -F 0.3 Vo HjOj. The most useful strain rate depends upon the alloy classification. 

Aluminium-sprayed coatings on steel have been exposed for over 20 years in very severe atmospheric conditions (such as those at Congella near Durban) and have given perfect protection the only result of long exposure has been the appearance of a few small nodules of aluminium oxide which appear to have little or no significance as sites of future corrosion. 

In atmospheric exposure to industrial environments its corrosion rate is only about one-third that of zinc and the corrosion reaction is stifled by the tenacious oxide which is produced nevertheless it can frequently function as an anodic coating both for steel and for the less corrosion-resistant aluminium alloys. 

Tests by Clark for the Corrosion Sub-committee of the American Welding Society were carried out at severe marine and industrial sites. After four years, the greatest protection to steel was given by sprayed aluminium coatings combined with aluminium vinyl paint in the following environments id) sea air, ib) sea-water immersion, (c) alternate sea-water immersion and exposure to air (tidal conditions) and id) industrial atmospheres contaminated with sulphur compounds. 

Exposure tests of 5-years duration in the atmosphere and during immersion in fresh water or sea-water by Welding Institute and by Stanners and Watkins have indicated the best paint systems for aluminium-coated steel. For immersed conditions two systems giving good performance are ... 

Pigments for finishes are selected on the basis of their colour, but special attention must be paid to inertness in the chosen binder and stability and light fastness under the conditions of application and exposure. Flake pigments such as aluminium and micaceous iron oxide give finishes of lower moisture-vapour permeability than conventional pigments, and consequently contribute to better protection. 

A number of cold-rolled alloys based on aluminium, copper and zinc are susceptible in varying degrees to recrystallisation on exposure to heat. This can have a detrimental effect on the adhesion of paint films. While there may, at first, be no sign of trouble, the defect will become obvious by brittleness of the film after some storage time has elapsed. 

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