Aluminum Retention Research Articles

Effect of Lactate on the Absorption and Retention of Aluminum in the Remnant Kidney Rat Model

In previous investigations we found the gastrointestinal absorption of aluminum (Al) to be enhanced in uremic rats and this phenomenon could not be attributed to either calcitriol deficiency or secondary hyperparathyroidism. The purpose of this study was to examine whether carboxyl ligands such as lactate could affect the absorption of A1 in our model and, if so, whether this would impose additional alterations on the A1 absorption in uremia. Uremic rats and controls were studied with single oral loads of either A1 chloride or A1 lactate and, subsequently, urinary A1 excretion was measured for 5 days. Compared with Al chloride, administration of A1 lactate resulted in significantly higher urinary excretion rates of A1 in uremic rats (55.5 +/- 22.7 vs. 27.4 +/- 7.0 micrograms; 2.06 +/- 0.84 vs. 1.01 +/- 0.26 mumol) and in controls (23.6 +/- 8.5 vs. 11.9 +/- 4.3 micrograms; 0.87 +/- 0.31 vs. 0.44 +/- 0.16 mumol). However, with either A1 load the recovery of A1 from urine was substantially higher in uremic animals. In contrast, only in controls was there a more pronounced rise in serum A1 concentrations following ingestion of A1 lactate, whereas in uremic rats this increase had a similar magnitude following A1 chloride and A1 lactate, suggesting a larger apparent volume of distribution of the latter. Adjustment of the pH of the A1 lactate-containing solution to 7.0 or oral administration of sodium lactate together with A1 chloride yielded essentially similar results. These observations indicate that the enhanced intestinal absorption of A1 in uremia is further augmented by lactate regardless of the mixture of hydroxolactato complexes employed.(ABSTRACT TRUNCATED AT 250 WORDS)

Aluminum accumulation during treatment with aluminum hydroxide and dialysis in children and young adults with chronic renal disease

Abstract Background. The control of hyperphosphatemia is a major clinical problem in patients with chronic renal failure receiving regular dialysis treatment. Despite continuing concern about aluminum toxicity, aluminum-containing antacids are still used in many of these patients as phosphate-binding agents. Although maximal acceptable doses of aluminum hydroxide have been recommended, the safety and efficacy of these guidelines have not been evaluated. Methods. Seventeen children and young adults (mean [±SD] age, 14.1 ±3.7 years) undergoing regular peritoneal dialysis were randomly assigned to treatment with either aluminum hydroxide (n = 7; maximal dose, 30 mg per kilogram of body weight per day) or calcium carbonate (n = 10; dose range, 2.5 to 12 g per day, according to serum phosphorus levels). Aluminum retention was assessed by serial measurements of plasma aluminum, deferoxamine-infusion tests, and measurements of bone aluminum content during a mean (±SD) follow-up of 13±2 months. The evolution of b...

Elevated Serum Aluminum Levels in Severely Burned Patients Who are Receiving Large Quantities of Albumin

Aluminum contaminates various fluids that are used in intravenous therapy, and it is associated with bone disease and encephalopathy. Albumin is highly contaminated with aluminum, which is eliminated primarily by renal excretion. Patients with burns receive large quantities of albumin and have impaired renal function, which puts them at hypothetical risk for aluminum loading. To assess the risk of aluminum loading we analyzed sera from 12 patients with burns for aluminum concentrations. Serum aluminum concentration was elevated in 8 of the 12 patients, and levels were at or near toxicity in 3 of the 8. Serum aluminum and serum creatinine levels directly correlated, r = 0.71 and p less than 0.005. No relation was found between serum aluminum and amount of albumin received. However, patients with the highest serum aluminum levels were the most severely burned and none survived. Thus patients with burns who are receiving albumin are at risk for aluminum loading. Impaired renal function contributes to aluminum retention.

Absorption and retention of aluminum from drinking water: 1. Effect of citric and ascorbic acids on aluminum tissue levels in rabbits

Adult, male New Zealand rabbits (three per group) were administered drinking water containing aluminum chloride (0, 100, or 500 mg Al/liter) together with citrate (0.11 m), ascorbate (0.11 m), or no added ligand ad libitum for 12 weeks. They were fed ad libitum regular rabbit chow analyzed to contain 297 mg Al/kg. Treatment had no effect upon food and water intake or weight gain during the experimental period. No effect of aluminum was observed on tissue levels of the essential metals zinc, copper, and iron, or on hemoglobin and hematocrit values. Aluminum levels were found to increase in a dose-dependent manner in stomach and intestinal mucosa, kidney, bone, urine, and feces. There was only a slight accumulation in liver, and no accumulation in brain (cerebral cortex or hippocampus). Although plasma aluminum was directly related to aluminum intake, whole blood aluminum bore no relation to aluminum dose. Citrate had no effect on aluminum accumulation in the stomach or intestine, but significantly enhanced plasma and bone aluminum levesl. Ascorbate did not enhance aluminum accumulation in any tissue studied and even prevented accumulation in bone. Both citrate and ascorbate enhanced excretion of aluminum. Ascorbate therapy may be of potential clinical use to enhance aluminum excretion.

Soil phosphorus fractions, aluminum, and water retention as affected by microbial activity in an Ultisol

Soil phosphorus fractions, aluminum, and water retention as affected by microbial activity in an Ultisol

Absorption and Retention of Aluminum from Drinking Water: 1. Effect of Citric and Ascorbic Acids on Aluminum Tissue Levels in Rabbits

Absorption and Retention of Aluminum from Drinking Water: 1. Effect of Citric and Ascorbic Acids on Aluminum Tissue Levels in Rabbits

A Study of the Reduction of Brine Permeability in Berea Sandstone With the Aluminum Citrate Process

Summary A systematic study of permeability modification of Berea sandstone by the injection of alternate slugs of polymer and aluminum citrate is described. The research included brine permeabilities from 10 to 300 md. Results of treatments with Pusher 700™ showed that permeability reduction was limited to the front end of the core (0 to 4 in. [0 to 10 cm]). The effective mobility of the treated region was so low that in-depth treatment of the remainder of the core was prevented. The amount and distribution of permeability reduction is related to both polymer and aluminum retention. The retention of aluminum was found to be a nonequilibrium process, varying with flow rate and thus residence time in the core. Aluminum was retained in large quantities in Berea core in the absence of polymer. Changing the treatment sequence to aluminum citrate/brine/polymer/brine yielded in-depth treatment of cores 12 to 48 in. [30 to 121 cm] in length. Both magnitude and persistence of permeability reduction were comparable to or better than those obtained with the combination process. Permeability increased with distance from the core inlet in most runs. This is believed to be caused by nonuniform distribution of retained aluminum.

Aluminum retention in a man-made Sphagnum wetland

Runoff from a highway interchange in western Maryland had Al concentrations averaging about 50 mg L−1, with a maximum of 206 mg L−1. As an alternative to expensive chemical treatment of this Al-rich water, in August 1984, the drainage was diverted through a 500 m2 man-made wetland, constructed from organic peat. For a 10 week period, Al concentrations in water leaving the wetland averaged 1.5 mg L−1. as compared to Al concentrations at the two major inflows to the wetland of 35.3 and 6.6 mg L−1. However, effective treatment of the drainage by the wetland was not observed over the entire 27 mo sampling period. Peat chemical analysis indicated that over the 27 mo, total Al concentration in the peat increased from 2375 μg g−1 to 13 634 μg g−1. Of this increase 5.5 % was contributed by exchangeable Al, 4.3% by adsorbed Al, 39.8% by organically bound Al, 33.1% by oxide bound Al, and 17.2% by precipitated and residual Al. Changes in Fe, Mn, Ca, Mg, K, and Na chemistry in the peat associated with Al retention are discussed.

Aluminium bone disease in patients receiving plasma exchange with contaminated albumin.

Aluminium balance studies were carried out on eight patients with various immunological disorders who were receiving plasma exchange with albumin solutions known to be contaminated with aluminium. Four patients with impaired renal function (creatinine clearance less than 50 ml/min) retained between 60% and 74% of the aluminium infused during a single plasma exchange. Transiliac bone biopsy specimens from three patients in this group had a high content of aluminium and showed histological evidence of current or previous bone disease related to aluminium. Two of these patients suffered intermittent bone pain. The main route of excretion of injected aluminium was in urine, only a small proportion of the total input being removed in the "plasma bag" during plasma exchange. The extent of aluminium retention and bone deposition was not reflected by the plasma aluminium concentration before or after plasma exchange. Treatment of five patients with intravenous desferrioxamine increased the plasma aluminium concentration and urinary output of aluminium in those with evidence of aluminium retention. These studies show that patients with poor renal function receiving treatment with albumin contaminated with aluminium retain the metal and deposit it in bone, where it may eventually cause aluminium bone disease. Plasma exchange should be used with caution in patients with renal impairment.

Plasma Aluminum Levels in Pediatric Dialysis Patients: Comparison of Hemodialysis and Continuous Ambulatory Peritoneal Dialysis

Accumulation of aluminum occurs in children with renal failure and can cause anemia, disabling osteodystrophy, and encephalopathy. Effects on bone mineralization are of particular concern in pediatric patients with growth potential. We measured plasma aluminum levels in 36 patients on continuous ambulatory peritoneal dialysis (CAPD) and 22 on hemodialysis under surveillance at a single pediatric center. The levels were above normal in 35 and 21 patients, respectively, and the values correlated with the oral dose of aluminum-containing phosphate-binding medications (r = 0.57; P less than 0.001). Younger and smaller children had higher plasma aluminum levels and also received larger doses of oral aluminum-containing compounds. Mean plasma aluminum levels (57.2 +/- 52.8 and 48.7 +/- 32.1 micrograms/liter, respectively) and the daily oral doses of elemental aluminum (47.3 +/- 37.6 and 39.2 +/- 26.7 mg/kg, respectively) were not statistically different in patients on CAPD and those on hemodialysis. Plasma aluminum levels did not correlate with estimated cumulative oral intake of aluminum, total duration of dialysis, serum calcium and phosphorus concentrations, N-terminal parathyroid hormone levels, or transfusion requirements. Retention of aluminum is common in children undergoing dialysis, correlates with the amount of aluminum administered orally, and results in similar elevations of plasma aluminum with CAPD and hemodialysis. Younger and smaller children are at increased risk for accumulation of aluminum. Alternative methods for control of serum phosphorus are needed in children with end-stage renal disease.

Effect of aluminum on porphyrin metabolism in hemodialyzed patients.

In patients with renal failure and on chronic hemodialysis, serum aluminum, serum delta-aminolevulinic acid, serum porphobilinogen and erythrocyte zinc protoporphyrin (ZPP) are significantly elevated, whereas erythrocyte delta-aminolevulinic acid dehydratase activity (ALAD, values in percent) is significantly reduced. The last two parameters (ZPP and ALAD) are statistically related to serum aluminum concentration (Al-S), but only the correlation between Al-S and ALAD remains statistically significant after standardization for the degree of renal insufficiency (expressed in terms of urea level). This study does not support the hypothesis that the retention of aluminum is responsible for the increase of ZPP in uremic patients on dialysis. The disturbances of porphyrin metabolism found in patients with renal failure and on chronic dialysis are not similar to those observed in porphyria cutanea tarda.

Uptake and retention of aluminum by dental enamel.

The uptake, depth of penetration, and retention of aluminum (Al) in sound and acid-etched dental enamel were determined following in vitro applications of solutions containing 0.005 M or 0.037 M Al. Compared with controls, significant amounts of Al uptake (approximately 2000 to 6000 ppm) were detected in both sound and etched enamel, with significantly more Al deposited in the latter. Analysis of successive layers of treated enamel demonstrated that Al was located predominantly within the first 20 microns of surface enamel. Only slight reductions in Al retention occurred following one week of water-soaking or one minute of brushing with water or dentifrice, indicating that Al was firmly bound by enamel.

Calcium balance in uremia: longitudinal study of long-term survivors.

Twelve male patients surviving uremia of 9-15 years duration were studied sequentially over a mean period of 9.2 years. Radiographs, bone biopsies, bone mineral mass (BMM) measured by photon absorptiometry, and total body calcium (TBC) determined by in vivo neutron activation analysis (NAA) were used. Pathologic fractures correlated with TBC corrected for height: 4 of 5 patients without fractures had TBC above 80% predicted, whereas 5 of 7 patients with fractures fell below this value. Unlike previous studies, negative calcium balance was seen in 3 patients with prolonged hyperparathyroidism. Though soft tissue calcification occurred in 6 patients, only 1 with massive shoulder calcification had an increase in TBC; this drawback of NAA has been previously overemphasized. Moreover, radial BMM also increased in 2 patients due to soft tissue calcification. When viewed at a single point in time, nearly all patients fell within the wide normal limits of BMM vs TBC. However, 6 patients with variable bone histology studied sequentially over a mean of 8.5 years showed significant preferential loss of radial bone mass compared to TBC. Aluminium retention did not influence calcium balance in these subjects.

Oxygen-initiated heterogeneous catalytic condensation of olefins in the presence of hydrogen: Conversion of pentene-2

Hydrogenation of glucose in distilled water and in buffer solution has been performed with promoted Raney nickel catalysts. The catalysts have been prepared from Ni2-xMx Al3, (where M = Cr,Fe,Co,Cu,Mo and x ≤ 0.4). The promoter metal, with thf 'exception of cobalt, favours aluminum retention in the catalyst, this high residual aluminum content could be partially responsible for the increase of the nickel activity observed in the presence of a metal M. Iron which is the most efficient promoter loses totally its activity in phosphate buffer at pH 6.1. The activity of Cr or Mo promoted nickel catalyst is about twice that of the unpromoted Raney nickel; in phosphate buffer the activity of these catalysts is enhanced but remains similar to that of the Raney nickel. Cobalt and copper present in small amounts do not change the properties of the Ni-Al system.

Influence of the conditions of cooling of a nickel-alumina alloy on activity of the skeletal nickel catalyst produced

Hydrogenation of glucose in distilled water and in buffer solution has been performed with promoted Raney nickel catalysts. The catalysts have been prepared from Ni2-xMx Al3, (where M = Cr,Fe,Co,Cu,Mo and x ≤ 0.4). The promoter metal, with thf 'exception of cobalt, favours aluminum retention in the catalyst, this high residual aluminum content could be partially responsible for the increase of the nickel activity observed in the presence of a metal M. Iron which is the most efficient promoter loses totally its activity in phosphate buffer at pH 6.1. The activity of Cr or Mo promoted nickel catalyst is about twice that of the unpromoted Raney nickel; in phosphate buffer the activity of these catalysts is enhanced but remains similar to that of the Raney nickel. Cobalt and copper present in small amounts do not change the properties of the Ni-Al system.

Chronic toxicity of aluminium in rats and mice and its effects on phosphorus metabolism.

In mice the oral LD₅₀ values of aluminium chloride and aluminium sulphate were 0·77 ± 0·12 and 0·98 ± 0·09 g. Al/kg. (± S.E.) respectively. Mice and rats were fed on a normal diet containing about 170 p.p.m. of aluminium. Doubling this concentration caused a decrease in growth in the second and third generations of mice. A high intake of aluminium sulphate (2,835 p.p.m.) caused a 20-fold increase of aluminium retention in white rats. Aluminium accumulated in various tissues, especially in the skeleton, liver, and testes. A high rate of intake (2,665 p.p.m.) caused a negative phosphorus balance in the rat, with an increased output of phosphorus in the faeces. The lower absorption of phosphorus was also demonstrated with Na₂H³²PO₄. Chronic and acute poisoning by aluminium chloride caused, after intraperitoneal Na₂H³²PO₄, decreased incorporation of ³²P into the phospholipids and nucleic acids of various tissues in the rat. It also caused a fall in the adenosinetriphosphate acid-levels in plasma, and a rise in the adenosine diphosphate level. The results suggest that the toxic effects of aluminium salts result both from decreased absorption of phosphorus and from interference with phosphorylation processes in the tissues.

Pulmonary effects of inhalation of aluminum by rats and hamsters.

Abstract Rats and hamsters exposed to atmospheres of powder or fume produced from aluminum showed a greater retention of aluminum in the latter exposure. Weights of wet lung, ash and aluminum oxide content of lungs were greater in the lungs of exposed rats than controls. Some subsequent reductions indicated clearance after fresh air. Initial response was proliferation of macrophages within alveolar spaces. Lipoid pneumonia followed. After long exposure to aluminum powder, rats showed focal deposits of hyalin material in alveolar walls. Large cystic spaces developed in some with acute pneumonia. Species difference but no evidence of fibrosis was shown in response to aluminum inhalation.

THE EXTENT OF THE RETENTION OF INGESTED ALUMINUM

This paper is one of a series1on the hygienic aspects of aluminum cooking utensils. It deals with the extent to which aluminum is stored in the tissues under conditions of a varied alimentary supply of soluble aluminum salts. The study of the elimination and the retention of aluminum is of importance, first, because aluminum is almost universally present in foodstuffs; secondly, because the metal is used extensively for the manufacture of cooking utensils and food containers; and, thirdly, because the data on the distribution of aluminum after feeding aluminum salts are of value in the elucidation of the absorption, retention and elimination of other metals. In addition to its natural occurrence, aluminum may enter foodstuffs by contact with the metal or by the addition of salts of aluminum. The extent to which aluminum enters foods cooked in aluminum utensils has been shown elsewhere1gto be extremely small,