BACKGROUND: On October 9, 2015, a 3-year-old boy (case one) presented to an emergency department with three weeks of anorexia, 2.7 Kg weight loss, decreased activity, and abdominal and leg pain. After excluding an initial diagnosis of rabies, heavy metal toxicity was suspected four weeks later. On November 11, laboratory testing identified high urine mercury level (29.5 µg/L). On November 12, the Florida Department of Health (DOH) in Hillsborough County was notified of the case by the Florida Poison Information Center Network.
METHODS: On November 13, 2015, the Florida Department of Environmental Protection tested the home and day care of case one in Hillsborough County. To identify additional cases, DOH-Hillsborough initiated an investigation including review of medical records; assessment of the day care by collaborating with other agencies; and phone interviews with the day care workers, visitors, and the parents of children attending the day care.
RESULTS: The investigation determined that in early July 2015 the day care owner had purchased an antique sphygmomanometer for the children to use as a play item. During play, the children pulled the device apart and it was removed from the play area approximately three weeks after it was introduced. Environmental assessment of the day care identified high mercury vapor levels ranging from 50 to 87 µg/m3. On November 20, remediation was completed and the day care was opened after mercury levels dropped to recommended levels for residential cleanup. Including case one, 23 individuals were tested for mercury. Sixteen individuals (10 children, 3 visitors, and 3 workers) had elevated blood or urine mercury levels (≥10 µg/L); 13 met the DOH surveillance case definition (12 confirmed and 1 probable) based on elevated mercury levels and illness consistent with mercury poisoning. Ages of cases ranged from <1 to 71 years (mean = 14.4 years). The majority were male (n=7, 53.8%), non-Hispanic white (n=13, 100%), and residents of Hillsborough County (n=11, 84.6%). Two cases (15.4%) were residents of Pasco County. Nine individuals (69.2%) received chelation therapy with only one dose of oral succimer to increase removal of mercury from the body.
CONCLUSIONS: This investigation highlights the importance of interagency coordination while responding to mercury spills and providing education to day care centers, children, child care providers, and parents about dangers of mercury and handling spills. DOH developed a fact sheet to provide this education and distributed it to the Department of Children and Families for use in day care centers.