Intoxication by manganese
Manganese is a very toxic metal. Acute poisonings with pure manganese do not occur. Under production conditions, chronic intoxications with manganese are of practical importance. Manganese enters the body through the respiratory tract, less often - through the gastrointestinal tract and skin. In case of chronic poisoning, manganese has general toxic effect on the body, with a primary lesion of the central nervous system (subcortical structures). Pathological studies showed plethora of organs, diffuse degenerative-dystrophic changes, mainly in the central nervous system. The disease develops 2-5 years after the start of work in conditions of increased concentrations of manganese in the air of the working area. Its earlier and later development is possible, even after the termination of contact. Symptoms of chronic intoxication caused by manganese develop gradually. There are three stages in the clinical picture of manganese intoxication: stage I is characterized by functional changes in the central nervous system in the form of an asthenovegetative syndrome; stage II - by toxic encephalopathy; stage III is a specific lesion of the striopallidal system - manganese-induced parkinsonism. The treatment is symptomatic, carried out in accordance with the stage of chronic manganese intoxication. There are no specific antidotes. Chronic manganese intoxication tends to progress even when contact is discontinued. Patients need rational employment outside contact with manganese and other toxic substances. The labour prognosis is generally favourable. If the qualification of the patients is reduced, they are referred for medical assessment to determine the degree of disability or disability group. The early diagnosis of chronic intoxication caused by manganese, the mechanization and sealing of the technological process, the reduction of dust formation and safety precautions when working with manganese are of particular importance. Pre-employment and periodic medical examinations of employees are mandatory.