Health evaluation of gold miners living in a mercury-contaminated village in Serra Pelada, Pará, Brazil.

Serra Pelada is a village in the Amazon region of Brazil where most of the inhabitants are former gold miners. Of 235 individuals evaluated, 219 were males (93.19%), 16 were females (6.80%), and the mean age was 52.07 years (standard deviation = 11.57). Most were heavy drinkers (62.44%) and smokers (70.30%), and 85.53% had previously suffered from malaria. Reported symptoms included fatigue (30.60%), irritability (35.62%), excitability (14.16%), insomnia (34.48%), memory loss (61.80%), visual field constriction (4.18%), paresthesia (64.93%), partial hearing loss (16.35%), and gingivitis (18.01%). After an examination of the residents, the authors observed several neurological symptoms: tremors (22.80%), involuntary ocular movement (2.20%), visual field constriction (4.18%), Romberg syndrome (2.33%), involuntary tongue movement (2.19%), dysdiadochokinesia (0.43%), failure of a finger-nose test (10.96%), failure of a knee-heel test (4.84%), inability to complete a tandem march (6.25%), muscular weakness (2.27%), and damage to sensory organs (24.66%). The authors concluded that these neurological changes possibly resulted from mercury toxicity; however, they could not determine a significant correlation with the mercury levels detected in participants' urine.