Lead poisoning of children in Africa, IV: Exposure to dust lead in primary schools in south-central Durban, South Africa.

Twenty primary schools in three areas (Merebank, Austerville and Bluff) of south-central Durban, South Africa were studied to determine if dust lead loading (microgram/m2) is high enough to constitute a risk to children. Atmospheric lead fallout rates in the schools varied from 9 to 264 micrograms/m2 per day and were higher than the values now being reported in the developed countries. Mean outside dust lead loadings were 425 micrograms/m2 in Merebank, 771 micrograms/m2 in Austerville and 1174 micrograms/m2 in Bluff areas, and 25% of the primary schools were found to have mean outside dust lead loading above 1000 micrograms/m2. Mean dust lead loadings inside classrooms were 2-4 times lower than the outside rates, and showed no significant difference among schools in the three areas. Dust lead loadings were correlated with lead concentrations in dust but not with distance from the highway or with atmospheric lead deposition rates. Exposure to dust lead in classrooms and in the school yard is considered to be an important contributor to blood lead levels in, and hence a potential health hazard to, children in many urban areas of the city.