Neurobehavioral Effects of Manganese Toxicity

Summary of Significant Neurological Disorders in Various Grades of 

Mild (manganese Asthenia anorexia insomnia muscular 

Moderate Speech disorders clumsiness of movements abnormal gait altered balance exaggerated refiexes in low er limbS expressionless facieS adiodokinesis and fine tremors 

Severe TremorS cock w alk rigidity in both the extremities spasmodic laughter 

Manganese encephalopathy could be produced in various species of animals by the administration of inorganic forms of the metal and after exposure to an organic compound, methyl-cylopentadienyl tricarbonyl manganese (MMT). The threshold of neuromuscular excitability was lowered in animals exposed to this compound, indicating increased sensitivity. Inhalation of manganese tricarbonyl compounds produced an increase in the threshold of neuromuscular excitability 7 months after the exposure of rats. A series of studies of repeated inhalation exposures 

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