Chronic Mercury Poisoning—Clinical Aspects

Chronic mercury poisoning, common in the past, still occurs today and the diagnosis even in those exposed in industry can be missed. Three cases of poisoning from a group of five workers exposed to mercury working in a firm making electrical apparatus showed between them the classical features of the disease. All had high values for urinary excretion of mercury and one worker had transient proteinuria which cleared as mercury excretion fell. Investigation showed the proteinuria to resemble that found in glomerular lesions of the kidney but no other functional abnormality was detected. All workers exposed to mercury should be kept under medical surveillance and regular examination of the urine should be performed. Those who develop proteinuria, as well as those with mercurialism, should be removed from further exposure until full recovery occurs.