The pediatric burden of disease from lead exposure at toxic waste sites in low and middle income countries

Background: The impact of lead from toxic waste sites on children in low and middle income countries has not been calculated due to a lack of exposure data. We sought to calculate this impact in Disability Adjusted Life Years (DALYs).

Materials and methods: Using an Integrated Exposure Uptake Biokinetic (IEUBK) model, we converted soil and drinking water lead levels from sites in the Blacksmith Institute[U+05F3]s Toxic Sites Identification Program (TSIP) into mean blood lead levels (BLLs). We then calculated the incidence of mild mental retardation (MMR) and DALYs resulting from these BLLs.

Results: The TSIP included 200 sites in 31 countries with soil (n=132) or drinking water (n=68) lead levels, representing 779,989 children younger than 4 years of age potentially exposed to lead. Environmental lead levels produced a range of BLLs from 1.56 to 104.71. μg/dL. These BLLs equated to an estimated loss of 5.41-8.23 IQ points, resulting in an incidence of MMR of 6.03 per 1000 population and 76.1 DALYs per 1000 population.

Discussion: Soil and water lead levels at toxic waste sites predict BLLs that lower the intelligence quotient (IQ), with the resulting MMR potentially limiting individual- and country-level development. The preventable burden of disease produced by these sites highlights the need for toxic waste sites to be systematically identified, evaluated, and remediated.