Exposure to Heavy Metals in Children Working at a Waste Disposal Site, and in Reference Children from Managua, Nicaragua

Abstract

ISEE-0906 Objective: The study aimed at assessing the exposure to heavy metals of children working at a waste disposal site in Nicaragua, and of referent children. Method: Concentrations of lead, mercury, cadmium and selenium were determined in blood samples obtained from 103 children aged 6–15 working at the Managua waste disposal site, 102 referent children from a nearby neighborhood (Acahualinca), and 34 children from a remote city area, being the socioeconomic conditions similar in all three cases. Exploratory soil sampling was also performed to investigate diffuse and point sources of lead contamination at the waste disposal area and in the neighborhood nearby. Results: The children working at the waste disposal site showed higher blood levels of lead, mercury and cadmium than the other children, 28% having lead levels higher than 100 μg/l, the level the Center for Disease Control (CDC) considers as action level; 36% of the referent having levels above 50 μg/l, a level suggested to induce subtle developmental and cognitive effects. In all the groups, the levels of mercury and cadmium observed were generally lower than those for which adverse health effects have been reported. The selenium status appeared adequate. The lead content in soil around homes located at the waste disposal site was higher than for homes in Acahualinca. Conclusions: Occupational and environmental exposure to heavy metals at the waste disposal site was observed. Lead is of major concern, both for the children themselves and the next generation. Many of the examined girls can be expected to soon be mothers since 21% of adolescent females in Managua have children or are pregnant. Urgent action is needed in order to reduce the impact on children's health of the condition noted.