Jack Caravanos

Approaches to systematic assessment of environmental exposures posed at hazardous waste sites in the developing world: the Toxic Sites Identification Program.

In the developing world, environmental chemical exposures due to hazardous waste sites are poorly documented. We describe the approach taken by the Blacksmith Institutes Toxic Sites Identification Program in documenting environmental chemical exposures due to hazardous waste sites globally, identifying sites of concern and quantifying pathways, populations, and severity of exposure. A network of local environmental investigators was identified and trained to conduct hazardous waste site investigations and assessments. To date, 2,095 contaminated sites have been identified within 47 countries having an estimated population at risk of 71,500,000. Trained researchers and investigators have visited 1,400 of those sites. Heavy metals are the leading primary exposures, with water supply and ambient air being the primary routes of exposure. Even though chemical production has occurred largely in the developed world to date, many hazardous waste sites in the developing world pose significant hazards to the health of large portions of the population. Further research is needed to quantify potential health and economic consequences and identify cost-effective approaches to remediation.

Burden of Disease from Toxic Waste Sites in India, Indonesia, and the Philippines in 2010

Background: Prior calculations of the burden of disease from toxic exposures have not included estimates of the burden from toxic waste sites due to the absence of exposure data. Objective: We developed a disability-adjusted life year (DALY)-based estimate of the disease burden attributable to toxic waste sites. We focused on three low- and middle-income countries (LMICs): India, Indonesia, and the Philippines. Methods: Sites were identified through the Blacksmith Institute’s Toxic Sites Identification Program, a global effort to identify waste sites in LMICs. At least one of eight toxic chemicals was sampled in environmental media at each site, and the population at risk estimated. By combining estimates of disease incidence from these exposures with population data, we calculated the DALYs attributable to exposures at each site. Results: We estimated that in 2010, 8,629,750 persons were at risk of exposure to industrial pollutants at 373 toxic waste sites in the three countries, and that these exposures resulted in 828,722 DALYs, with a range of 814,934–1,557,121 DALYs, depending on the weighting factor used. This disease burden is comparable to estimated burdens for outdoor air pollution (1,448,612 DALYs) and malaria (725,000 DALYs) in these countries. Lead and hexavalent chromium collectively accounted for 99.2% of the total DALYs for the chemicals evaluated. Conclusions: Toxic waste sites are responsible for a significant burden of disease in LMICs. Although some factors, such as unidentified and unscreened sites, may cause our estimate to be an underestimate of the actual burden of disease, other factors, such as extrapolation of environmental sampling to the entire exposed population, may result in an overestimate of the burden of disease attributable to these sites. Toxic waste sites are a major, and heretofore underrecognized, global health problem.

Blood Lead Levels in Mexico and Pediatric Burden of Disease Implications

BACKGROUND Although there has been success in reducing lead exposure with the phase-out of leaded gasoline, exposure to lead in Mexico continues to threaten the health of millions, much of which is from lead-based glazes used in pottery that leaches into food. OBJECTIVES An extensive historical review and analysis of available data on blood lead levels in Mexican populations was conducted. We used a calculated geometric mean to evaluate the effect of lead on the pediatric burden of disease. METHODS An extensive bibliographic search identified 83 published articles from 1978 to 2010 with blood lead level (BLL) data in Mexican populations representing 150 data points from more than 50,000 study participants. Values from these publications were categorized into various groupings. We then calculated the incidence of disease and disability-adjusted life-years resulting from these BLLs using the World Health Organizations burden of disease spreadsheets for mild mental retardation. RESULTS Reviewing all relevant studies, the geometric means of Mexican BLLs in urban and rural areas were found to be 8.85 and 22.24 ug/dL, respectively. Since the phase-out of leaded gasoline, the mean in urban areas was found to be 5.36 ug/dL and the average in rural areas is expected to be much higher. The U.S. Centers for Disease Control and Preventions (CDC) upper limit of blood lead in children under the age of 6 years is 5 ug/dL and the current U.S. average is 1.2 ug/dL. Our results indicate that more than 15% of the population will experience a decrement of more than 5 IQ points from lead exposure. The analysis also leads us to believe that lead is responsible for 820,000 disability-adjusted life-years for lead-induced mild mental retardation for children aged 0 to 4 years. CONCLUSION Lead continues to threaten the health of millions and remains a significant cause of disability in Mexico. Additional interventions in reducing or managing lead-based ceramic glazes are necessary to protect the public health.

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 Institutes 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.

The burden of disease from pediatric lead exposure at hazardous waste sites in 7 Asian countries

Identification and systematic assessment of hazardous wastes sites in low and middle-income countries has lagged. Hazardous waste problems are especially severe in lower income Asian countries where environmental regulations are non-existent, nonspecific or poorly enforced. In these countries extensive unregulated industrial development has created waste sites in densely populated urban areas. These sites appear to pose significant risks to public health, and especially to the health of children. To assess potential health risks from chemical contamination at hazardous waste sites in Asia, we assessed 679 sites. A total of 169 sites in 7 countries were classified as contaminated by lead. Eighty-two of these sites contained lead at levels high enough to produce elevated blood lead levels in surrounding populations. To estimate the burden of pediatric lead poisoning associated with exposure to lead in soil and water at these 82 lead-contaminated sites, we used standard toxicokinetic models that relate levels of lead in soil and water to blood lead levels in children. We calculated blood lead levels, and we quantified losses of intelligence (reductions in IQ scores) that were attributable to lead exposure at these sites. We found that 189,725 children in the 7 countries are at risk of diminished intelligence as a consequence of exposure to elevated levels of lead in water and soil at hazardous waste sites. Depending on choice of model, these decrements ranged from 4.94 to 14.96 IQ points. Given the restricted scope of this survey and the conservative estimation procedures employed, this number is almost certainly an underestimate of the full burden of disease. Exposure to toxic chemicals from hazardous waste sites is an important and heretofore insufficiently examined contributor to the Global Burden of Disease.

Prevalence and predictors of residential health hazards: a pilot study.

Abstract This article reports the results of a pilot study designed to ascertain the prevalence of lead-based paint (LBP), vermin, mold, and safety conditions and hazards and to validate observations and self-reports against environmental sampling data. Data are based on a convenience sample of 70 dwellings in a low-income, urban neighborhood in Brooklyn, New York. The vast majority of residences (96%) contained multiple conditions and/or hazards: LBP hazards (80%), vermin (79%), elevated levels of airborne mold (39%), and safety hazards (100%). Observations and occupant reports were associated with environmental sampling data. In general, the more proximate an observed condition was to an actual hazard, the more likely it was to be associated with environmental sampling results (e.g., peeling LBP was associated with windowsill dust lead levels, and cockroach sightings by tenants were associated with Blatella germanica [Bla g 1] levels). Conversely, the more distal an observed condition was to an actual hazard, the less likely it was to be associated with environmental sampling results (e.g., water damage, alone, was not statistically associated with elevated levels of dust lead, Bla g 1, or airborne mold). Based on the findings from this pilot study, there is a need for industrial hygienists and others to adopt more comprehensive and integrative approaches to residential hazard assessment and remediation. Further research—using larger, randomly drawn samples, representing a range of housing types and geographical areas—is needed to clarify the relationship between readily observable conditions, occupant reports, and environmental sampling data and to assess the cumulative impact on human health.

Childhood Blood Lead Reductions Following Removal of Leaded Ceramic Glazes in Artisanal Pottery Production: A Success Story

Background. Lead exposure within artisanal ceramics workshop communities in Mexico continues to be a major source of childhood lead poisoning. Artisanal ceramics workshops expose children through d...

Exploratory Health Assessment of Chemical Exposures at E-Waste Recycling and Scrapyard Facility in Ghana

Background. Ghana is one of several West African countries receiving high volumes of used electric and electronic equipment and waste. Within the capital city of Accra, one scrapyard has been the s...

Rapid assessment of environmental health risks posed by mining operations in low- and middle-income countries: selected case studies

Previous studies have evaluated associated health risks and human exposure pathways at mining sites. Others have provided estimates of the scale of the issue based in part on surveys. However, a global census of mining-related hazardous waste sites has been lacking. The Toxic Sites Identification Program (TSIP) implemented by Blacksmith Institute (New York, NY, USA) since 2009 is an ongoing effort to catalogue a wide range of chemically contaminated sites with a potential human health risk (Ericson et al., Environ Monit Assess doi:10.1007/s 10661-012-2665-2, 2012). The TSIP utilizes a rapid assessment instrument, the Initial Site Screening (ISS), to quickly and affordably identify key site criteria including human exposure pathways, estimated populations at risk, and sampling information. The resulting ISS allows for comparison between sites exhibiting different contaminants and pollution sources. This paper explores the results of a subset of ISSs completed at 131 artisanal and small-scale gold mining areas and 275 industrial mining and ore processing sites in 45 countries. The authors show that the ISS captures key data points, allowing for prioritization of sites for further investigation or remedial activity.

Burden of disease resulting from lead exposure at toxic waste sites in Argentina, Mexico and Uruguay

BackgroundThough lead contaminated waste sites have been widely researched in many high-income countries, their prevalence and associated health outcomes have not been well documented in low- and middle-income countries.MethodsUsing the well-established health metric disability-adjusted life year (DALY) and an exposure assessment method developed by Chatham-Stephens et al., we estimated the burden of disease resulting from exposure to lead at toxic waste sites in three Latin American countries in 2012: Argentina, Mexico and Uruguay. Toxic waste sites identified through Pure Earth’s Toxic Sites Identification Program (TSIP) were screened for lead in both biological and environmental sample media. Estimates of cardiovascular disease incidence and other outcomes resulting from exposure to lead were utilized to estimate DALYs for each population at risk.ResultsApproximately 316,703 persons in three countries were at risk of exposure to pollutants at 129 unique sites identified through the TSIP database. Exposure to lead was estimated to result in between 51,432 and 115,042 DALYs, depending on the weighting factor used. The estimated burden of disease caused by exposure to lead in this analysis is comparable to that estimated for Parkinson’s disease and bladder cancer in these countries.ConclusionsLead continues to pose a significant public health risk in Argentina, Mexico, and Uruguay. The burden of disease in these three countries is comparable with other widely recognized public health challenges. Knowledge of the relatively high number of DALYs associated with lead exposure may be used to generate support and funding for the remediation of toxic waste sites in these countries and others.