Manganese Poisoning in Moroccan Miners

While there is very little in the literature about criminal or accidental manganese poisoning, man ganese ores and their industrial applications give rise to a number of cases of occupational poisoning. The historical background of the condition has already been reviewed in a previous paper (Rodier and Rodier, 1949) but it should be noted that this occupational disease has been recognized since 1837 when Couper of Glasgow observed the first cases among five manganese ore crushers. He described a series of nervous phenomena : muscular weakness, paraplegia, tremor of the extremities, a tendency to lean forward while walking, whispering speech, and salivation. Since then a number of writers have made further observations and recognized manganese as a poison affecting the central nervous system. It is less well known than other metallic poisons. It continues to be rare since only a limited number of workers come in contact with manganese in a dangerous form. The symptoms, which progress as a rule to total disablement, render it one of the most serious occupational hazards. It poses important social problems, as much concerning the rehabilitation of partially incapacitated labourers, as the care of the sick man and his family by the community.