Toxicity magnesium

MAGNESiUM SALiCYLATE A sodium free salicylate derivative that may have a low incidence of Gl upset. The product labeling and dosage are expressed as magnesium salicylate anhydrous. The possibility of magnesium toxicity exists in people with renal insufficiency. 

After the initial IV dose, some clinicians administer 1 to 2 g/hr by constant IV infusion. Subsequent IM doses of 4 to 5 g magnesium sulfate may be injected into alternate buttocks every 4 hours, depending on the presence of the patellar reflex, adequate respiratory function, and absence of signs of magnesium toxicity. Continue therapy until paroxysms cease. 

Children When administered by continuous IV infusion (especially for more than 24 hours preceding delivery) to control convulsions in toxemic mothers, the newborn may show signs of magnesium toxicity, including neuromuscular or respiratory depression. 

Magnesium deficiency, usually the result of decreased absorption or excessive excretion, results in neuromuscular weakness and ultimately convulsions. Dietary deficiency in catde is known as the grass staggers. Magnesium toxicity from impaired excretion or excessive consumption of antacids results in vomiting, hypertension, and central nervous systems effects. Inhalation of magnesium oxide from welding can cause metal fume fever similar to that from zinc. 

What signs and symptoms should be monitored if a woman is prescribed magnesium sulphate and what is prescribed if signs of magnesium toxicity are observed ... 

Magnesium toxicity can be assessed clinically as it causes loss of deep tendon reflexes and respiratory depression. 

Calcium gluconate 1 g (10 mL) is given by slow intravenous injection (over 10 min) for magnesium toxicity. 

Saline laxatives (magnesium citrate, magnesium sulfate, sodium sulfate, and disodium phosphate) or saccharide laxatives (sorbitol, mannitol, lactulose) are also used in poisoned patients. Common adverse effects are abdominal cramps, excessive diarrhea, and abdominal distension. Dehydration and electroljde imbalance in children, and hjrpermagnesemia and magnesium toxicity (with magnesium-based cathartics) have also been reported. 

Acute toxicity can arise from overdosage or intestinal or renal disease. The main symptoms of magnesium toxicity are neuromuscular (paralysis) and cardiac (electrocardiographic changes, hypotension, bradycardia, heart block). In more severe cases there will be nervous system or respiratory depression, hypomotility of the bowel, muscle paralysis, and hyporeflexia. 

Fassler CA, Rodriguez RM, Badesch DB, Stone WJ, Marini JJ. Magnesium toxicity as a cause of hypotension and hypoventilation. Occurrence in patients with normal renal function. Arch Intern Med 1985 145(9) 1604-6. 

Magnesium salicylate has a low incidence of Gl side effects. Both sodium salicylate and magnesium salicylate should be used cautiously in individuals in whom excessive amounts of these electrolytes might be detrimental. The possibility of magnesium toxicity in individuals with renal insufficiency exists. It is available as tablets, but its safety in children under 12 years of age has not been fully determined. 

Monitoring signs of magnesium toxicity such as hot flushed skin, anxiety, lethargy, hypotension and laryngeal stridor. 

Although the vital signs are within normal range, the respiratory rate and pulse are both on the lower end of normal and easily could be depressed if magnesium toxicity occurs. 

TOXICITY. Magnesium toxicity may occur when the kidneys are unable to get rid of a large overload characterized by slowed breathing, coma, and sometimes death. It is noteworthy that magnesium salts taken by pregnant mothers may affect their newborn babies. 

Triaryl phosphates are produced by reaction of phosphoms oxychloride with phenoHc compounds at 100—200°C with magnesium or aluminum chloride catalyst. Past use of cresols and xylenols from coal tar or petroleum is replaced for lower toxicity and cost by synthetic phenoHcs, primarily isopropyl phenol, /-butyl phenol, and phenol itself A range of viscosities is achieved by selection and proportioning of the phenols and their isomers used for the starting material. 

Magnesium is essential to most plant and animal life (see Mineral NUTRIENTS). Dietary deficiency, rather than toxicity, is the more significant problem. 

Safety. Magnesium oxide (fume) has a permissible exposure limit (PEL) (134) (8 hours, TWA), of 10 mg/m total dust and 5 mg/m respirable fraction. Tumorigenic data (intravenous in hamsters) show a TD q of 480 mg/kg after 30 weeks of intermittent dosing (135), and toxicity effects data show a TC q of 400 mg/m for inhalation in humans (136). Magnesium oxide is compatible with most chemicals exceptions are strong acids, bromine pentafluoride, chlorine trifluoride, interhalogens, strong oxidizers, and phosphorous pentachloride. 

Some metals used as metallic coatings are considered nontoxic, such as aluminum, magnesium, iron, tin, indium, molybdenum, tungsten, titanium, tantalum, niobium, bismuth, and the precious metals such as gold, platinum, rhodium, and palladium. However, some of the most important poUutants are metallic contaminants of these metals. Metals that can be bioconcentrated to harmful levels, especially in predators at the top of the food chain, such as mercury, cadmium, and lead are especially problematic. Other metals such as silver, copper, nickel, zinc, and chromium in the hexavalent oxidation state are highly toxic to aquatic Hfe (37,57—60). 

Strontium Chromate. Strontium chromate [7789-06-2] SrCrO, is made by precipitation of a water-soluble chromate solution using a strontium salt or of chromic acid using a strontium hydroxide solution. It has a specific gravity of 3.84 and is used as alow toxicity, yellow pigment and as an anticorrosive primer for zinc, magnesium, alurninum, and alloys used in aircraft manufacture (8) (see Corrosion and corrosion control). 

Because of its extreme insolubiUty, barium sulfate is not toxic the usual antidote for poisonous barium compounds is to convert them to barium sulfate by administering sodium or magnesium sulfate. In medicine, barium sulfate is widely used as an x-ray contrast medium (see Imaging TECHNOLOGY X-RAY technology). It is also used in photographic papers, filler for plastics, and in concrete as a radiation shield. Commercially, barium sulfate is sold both as natural barite ore and as a precipitated product. Blanc fixe is also used in making white sidewall mbber tires or in other mbber appHcations. 

No fewer than 14 pure metals have densities se4.5 Mg (see Table 10.1). Of these, titanium, aluminium and magnesium are in common use as structural materials. Beryllium is difficult to work and is toxic, but it is used in moderate quantities for heat shields and structural members in rockets. Lithium is used as an alloying element in aluminium to lower its density and save weight on airframes. Yttrium has an excellent set of properties and, although scarce, may eventually find applications in the nuclear-powered aircraft project. But the majority are unsuitable for structural use because they are chemically reactive or have low melting points." ... 

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