Low toxicity of magnesium and magnesium compounds gives them high possibilities. No reports of serious poisoning in industry have appeared in literature. No unusual health hazard has been found associated with the handling, mechanical finishing, or pickling of magnesium alloys, including those containing thorium or beryllium. No evidence is available that inhalation of magnesium dust can cause lung damage. However, fine magnesium dust is generated in the printing trade, and complaints have been made about discolored sputum. The acute oral toxicity of magnesium compounds in animals is low, too. In spite of that oral intake can reduce kidney function. You can find any problem by toxic symptoms like blood pressure and respiratory paralysis, disturbs the cofactor for enzymes, problems with central nervous system and others.
Toxic response includes general anesthesia and narcosis. Intravenous administration of calcium neutralizes the reaction. In the cardiovascular system, some of the effects of excess magnesium are similar to those of potassium. Magnesium has a direct depressant effect on skeletal muscle.
Normal adult dietary intake is 300-400 mg/day. Drastic reduction of dietary intake of magnesium is needed to induce a negative balance because of extremely effective renal retention and increasing intestinal absorption. The effect of magnesium (as well as of zinc) supplementation and depletion on carcinogenesis has been reviewed comprehensively. Magnesium supplementation tends to inhibit carcinogenesis, and magnesium deficiency increases the incidence of neoplasia in humans and animals. Fatal intoxication of magnesium sulfate and magnesium hydroxide (milk of magnesia) can occur with very high dietary levels (15,000-25,000 p pm) or under circumstances that increase magnesium absorption.
Particles of metallic magnesium that perforate the skin or gain entry through cuts and scratches may produce a severe local lesion characterized by evolution of gas and an acute inflammatory reaction, frequently with necrosis (chemical gas gangrene). Today the most serious hazard presented by magnesium is the danger of burns from molten metal.
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