[3145.5] The Pediatric Burden of Disease from Lead Exposure at Toxic Waste Sites in Low and Middle Income Countries
Kevin Chatham-Stephens, Jack Caravanos, Bret Ericson, Philip J. Landrigan, Richard Fuller. Preventive Medicine, Mount Sinai School of Medicine, New York, NY; School of Public Health at Hunter College, City University of New York, New York, NY; Blacksmith Institute, New York, NY.
BACKGROUND: Lead is a developmental neurotoxicant. Exposure in early life reduces IQ, disrupts behavior, and can cause mental retardation. Mental retardation and IQ loss caused by lead can, if widespread, limit country and regional development Due to lack of exposure data, the societal impact of lead from toxic waste sites in low and middle income countries (LMICs) has not previously been calculated.
OBJECTIVE: To calculate the burden of disease in Disability Adjusted Life Years (DALYs) in children from lead exposure at toxic waste sites in 35 LMICs.
DESIGN/METHODS: Sites were identified through Blacksmith Institute's Toxic Sites Identification Program, a global effort to identify waste sites in LMICs. Soil and drinking water lead levels were determined through environmental sampling. Utilizing the US EPA's Integrated Exposure Uptake Biokinetic (IEUBK) Model for Lead in Children, we estimated blood lead levels (BLLs) from the environmental data. Combining data on population size with projected BLLs, we estimated the incidence of mild mental retardation from lead exposure and calculated the resulting DALYs.
RESULTS: As of August 2012, the Blacksmith database contained 200 sites in 35 countries with soil (n = 132) or drinking water (n = 68) lead levels. 779,989 children under the age of 4 years are at risk of lead exposure, with a mean population per site of 3,900 children. Soil lead levels ranged from 55 to 30,000 mg/kg, while drinking water lead levels ranged from 5 to 6,000 μg/L. These environmental lead levels produced an estimated range of BLLs from 1.56 to 104.71 µg/dL. Eighty six percent of children had BLLs greater than 5 µg/dL, and at 75 sites 100% of BLLs were predicted to be greater than 5 µg/dL. These BLLs produced an average IQ loss of 8.19 points. This reduction in IQ results in an incidence of mild mental retardation of 5.29 per 1,000 person years, equaling 67.1 DALYs per 1,000 person years.
CONCLUSIONS: This analysis documents that almost 800,000 children under the age of four years are potentially exposed to lead from 200 toxic waste sites in 35 countries. These findings almost certainly underestimate the full magnitude of the disease burden, because many sites in LMICs have not yet been identified or characterized. The burden of disease produced by toxic waste sites in LMICs is substantial, highlighting the need for these sites to be identified, evaluated and remediated.
First Author is a Fellow in Training
Session: Platform Session: Epidemiology: Hot Topics in Epidemiology (8:00 AM - 10:00 AM)
Date/Time: Monday, May 6, 2013 - 9:00 AM
Room: 152A - Walter E. Washington Convention Center
Course Code: 3145