Mercury poisoning manifested as acrodynia, reported in a four year old boy in Michigan ten day after the inside of his home was painted with 64 liters of interior latex paint containing phenylmercuric acetate, prompted an investigation by the Division of Environmental Hazards and Health Effects, Centers for Disease Control, Atlanta, GA. Nineteen families were recruited from a list of more than 100 persons who called the Michigan Department of Public Health after a press release announced that some interior latex paint contained more than the recommended limit of mercury of 1.5 mmol per liter. The median mercury content of the paint in 29 cans sampled from the exposed households was 3.8 mmol per liter. The concentrations of mercury in the air samples obtained from homes of exposed families were significantly higher than in the unexposed households. Urinary mercury concentrations were significantly higher among the exposed persons than among unexposed persons (4.7 mmol of mercury per millimole of creatinine compared to 1.1 mmol per millimole). These mercury concentrations in exposed persons have been associated with symptomatic mercury poisoning. [1]

COMMENT. Exposed children had the highest urinary mercury concentrations and young children may be at increased risk since vapors containing mercury are heavier than indoor air and tend to settle toward the floor. Individual exposure to mercury varies with the time spent in painted rooms, the depth and frequency of inhalation, the degree of ventilation in the room, and the likely decrease in mercury vapors over time. Opening all windows and doors decreased the concentration of mercury but it returned to the unventilated value within three hours of closing doors and windows. Mercury is released from surfaces coated with a paint containing mercury after the paint has dried. In the body phenylmercuric acetate is broken down to form inorganic mercury which accumulates in the kidney, the brain, and the fetus, and is excreted in the urine. A urinary mercury concentration of less than 100 nmol per liter is considered acceptable for adults but a background urinary mercury concentration for children has not been established. In the four year old boy who developed acrodynia, a 24 hour urine sample contained 324 nmol of mercury per liter. The clinical manifestations of acrodynia in this child included leg cramps, a generalized rash, pruritus, sweating, tachycardiac, an intermittent low-grade fever, marked personality change, erythema and desquamation of the hands, feet, and nose, weakness of the pelvic and pectoral girdles, and lower extremity nerve dysfunction developing sequentially. On June 29, 1990 the Environmental Protection Agency announced that compounds containing mercury could no longer be lawfully added to interior latex paint after August 20, 1990. If paint containing mercury is employed then proper ventilation must be insured. The history of mercury poisoning and its manifestation as acrodynia in children is reviewed in an editorial [2]. Dimercaptosuccinic acid given orally is the most promising therapy.