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.     

Attributable risk analysis reveals potential healthcare savings from increased consumption of dairy products

With rising burdens of obesity and chronic disease, the role of diet as a modifiable risk factor is of increasing public health interest. There is a growing body of evidence that low consumption of dairy products is associated with elevated risk of chronic metabolic and cardiovascular disorders. Surveys also suggest that dairy product consumption falls well below recommended targets for much of the population in many countries, including the USA, UK, and Australia. We reviewed the scientific literature on the health effects of dairy product consumption (both positive and negative) and used the best available evidence to estimate the direct healthcare expenditure and burden of disease [disability-adjusted life years (DALY)] attributable to low consumption of dairy products in Australia. We implemented a novel technique for estimating population attributable risk developed for application in nutrition and other areas in which exposure to risk is a continuous variable. We found that in the 2010-2011 financial year, AUD$2.0 billion (USD$2.1 billion, €1.6 billion, or ～1.7% of direct healthcare expenditure) and the loss of 75,012 DALY were attributable to low dairy product consumption. In sensitivity analyses, varying core assumptions yielded corresponding estimates of AUD$1.1-3.8 billion (0.9-3.3%) and 38,299-151,061 DALY lost. The estimated healthcare cost attributable to low dairy product consumption is comparable with total spending on public health in Australia (AUD$2.0 billion in 2009-2010). These findings justify the development and evaluation of cost-effective interventions that use dairy products as a vector for reducing the costs of diet-related disease.     

Potential cost-effectiveness of vaccination for rotavirus gastroenteritis in eight Latin American and Caribbean countries.

OBJECTIVES: To estimate the costs, benefits and cost-effectiveness of vaccination for rotavirus gastroenteritis in eight Latin American and Caribbean countries: Argentina, Brazil, Chile, the Dominican Republic, Honduras, Mexico, Panama, and Venezuela. METHODS: An economic model was constructed to estimate the cost-effectiveness of vaccination from the health care system perspective, using national administrative and published epidemiological evidence, country-specific cost estimates, and vaccine efficacy data. The model was applied to the first five years of life for the 2003 birth cohort in each country. The main health outcome was the disability-adjusted life year (DALY), and the main summary measure was the incremental cost per DALY averted. A 3% discount rate was used for all predicted costs and benefits. Sensitivity analyses evaluated the impact of uncertainty regarding key variables on cost-effectiveness estimates. RESULTS: According to the estimates obtained with the economic model, vaccination would prevent more than 65% of the medical visits, deaths, and treatment costs associated with rotavirus gastroenteritis in the eight countries analyzed here. At a cost of US$ 24 per course (for a two-dose vaccine), the incremental cost-effectiveness ratio ranged from 269 US dollars/DALY in Honduras to 10,656 US dollars/DALY in Chile. Cost-effectiveness ratios were sensitive to assumptions about vaccine price, mortality, and vaccine efficacy. CONCLUSIONS: Vaccination would effectively reduce the disease burden and health care costs of rotavirus gastroenteritis in the Latin American and Caribbean countries analyzed here. From the health care system perspective, universal vaccination of infants is predicted to be cost-effective, based on current standards.     

How developing nations can protect children from hazardous chemical exposures while sustaining economic growth

Increasing worldwide use of chemicals, including heavy metals used in industry and pesticides used in agriculture, may produce increases in chronic diseases in children unless steps are taken to manage the production, use, trade, and disposal of chemicals. In 2020 the developing world will account for 33 percent of global chemical demand and 31 percent of production, compared with 23 percent and 21 percent, respectively, in 1995. We describe present and potential costs of environmental exposures and discuss policy options to protect future generations of children in a sustainable development context. Specifically, we describe the principles of sound chemicals management, as follows: precaution, or the use of cost-effective measures to prevent potentially hazardous exposures before scientific understanding is complete; the right to know, or informing the public--especially vulnerable groups--in a timely fashion about the safe use of chemicals and any releases of chemicals into the environment; pollution prevention, or preventing the use of hazardous chemicals and the production of pollutants, rather than focusing on managing wastes; internalization of environmental and health costs, or ensuring that the consequences of exposures are reflected in the price of chemicals through such approaches as "polluter pays"; and use of best available scientific information in making decisions such as what chemicals to allow into the market. We recommend that industrializing nations in particular employ these principles to prevent disease among their populations while at the same time minimizing the risk to their own economic development.     

National exposure measurements for decisions to protect public health from environmental exposures

Protecting public health from environmental exposures requires four steps: detection of exposures known or expected to cause disease, assessment of health risk from exposure, implementation of an exposure intervention, and assurance that the exposure intervention is effective. To prioritize efforts in these four areas one must consider the size of the population affected, the seriousness of health effects, and the availability of cost-effective exposure interventions. Population exposure data is critical to each of these steps for protecting health. Biomonitoring data for the US population is now available to assist public health scientists and physicians in preventing disease from environmental exposures, and it complements that available for levels of chemicals in environmental media. The Second National Report on Human Exposure to Environmental Chemicals provides for the US population serum, blood and urine levels for 116 environmental chemicals over the years 1999 and 2000, with separate analyses by age, sex, and race/ethnicity. This national exposure information identifies which chemicals get into Americans in measurable quantities; determines whether exposure levels are higher among population subgroups; determines how many Americans have levels of chemicals above recognized health threshold levels (for chemicals with such threshold levels); establishes reference ranges that define general population exposure so unusual exposures can be recognized; assesses the effectiveness of public health efforts to reduce population exposure to selected chemicals; and tracks over time trends in US population exposure. Blood lead measurements in the population were important in identifying lead in gasoline as a significant source of human lead exposure and documenting the reduction in blood lead levels in the population as a result of removing lead from gasoline and other products in the United States. Serum cotinine levels in the early 1990s found more widespread exposure to environmental tobacco smoke (ETS) in the United States than previously thought and additional measurements in 1999 and 2000 documented major declines in exposure to ETS as a result of public health actions in the 1990s. A new biomonitoring assessment of the exposure of the US population will be released every 2 years as the "National Report on Human Exposure to Environmental Chemicals." These reports will include the current 116 chemicals and new chemicals added to monitor priority exposures of the population.     

Cost-effectiveness and economic benefits of vaccines in low- and middle-income countries: A systematic review

Background

Public health interventions that prevent mortality and morbidity have greatly increased over the past decade. Immunization is one of these preventive interventions, with a potential to bring economic benefits beyond just health benefits. While vaccines are considered to be a cost-effective public health intervention, implementation has become increasingly challenging. As vaccine costs rise and competing priorities increase, economic evidence is likely to play an increasingly important role in vaccination decisions.

Methods

To assist policy decisions today and potential investments in the future, we provide a systematic review of the literature on the cost-effectiveness and economic benefits of vaccines in low- and middle-income countries from 2000 to 2010. The review identified 108 relevant articles from 51 countries spanning 23 vaccines from three major electronic databases (Pubmed, Embase and Econlit).

Results

Among the 44 articles that reported costs per disability-adjusted life year (DALY) averted, vaccines cost less than or equal to $100 per DALY averted in 23 articles (52%). Vaccines cost less than $500 per DALY averted in 34 articles (77%), and less than $1000 per DALY averted in 38 articles (86%) in one of the scenarios. 24 articles (22%) examined broad level economic benefits of vaccines such as greater future wage-earning capacity and cost savings from averting disease outbreaks. 60 articles (56%) gathered data from a primary source. There were little data on long-term and societal economic benefits such as morbidity-related productivity gains, averting catastrophic health expenditures, growth in gross domestic product (GDP), and economic implications of demographic changes resulting from vaccination.

Conclusions

This review documents the available evidence and shows that vaccination in low- and middle-income countries brings important economic benefits. The cost-effectiveness studies reviewed suggest to policy makers that vaccines are an efficient investment. This review further highlights key gaps in the available literature that would benefit from additional research, especially in the area of evaluating the broader economic benefits of vaccination in the developing world.     

Health-economic burden of obesity in Europe

Although overweight and obesity have long been recognised as major risk factors for a number of chronic diseases, lifestyle developments have led to substantial increases in bodyweight worldwide. In addition to their negative effects on health and quality of life, obesity and associated comorbidities may have a considerable impact on healthcare expenditures. The aim of this systematic review was to summarise cost estimates and compare costs attributable to obesity across different European countries. A structured search in MEDLINE, EMBASE, and all EBM Reviews was conducted to identify relevant literature. Two researchers independently assessed publications according to pre-defined inclusion criteria and with regard to study methodology. Costs attributable to obesity were extracted from the included studies and calculated relative to country-specific gross domestic income. Out of 797 publications that met our search criteria, 13 studies investigating 10 Western European countries were determined to be relevant and included in our review. Obesity-related healthcare burdens of up to 10.4 billion euros were found. Reported relative economic burdens ranged from 0.09% to 0.61% of each country's gross domestic product (GDP). Obesity appears to be responsible for a substantial economic burden in many European countries, and the costs identified in the available studies presumably reflect conservative estimates. There remains a great need for prospective and standardised studies to provide more accurate estimates of costs for all European countries.     

Mesothelioma in vehicle mechanics: is the risk different for Australians?

BACKGROUND: The question of whether vehicle mechanics have an increased risk of mesothelioma has important public health implications. Calculations of relative risk using case reports from the Australian Mesothelioma Registry (AMR) indicate increased risks; however, this contrasts with the results of 19 epidemiologic studies that have found no association. AIM: To evaluate potential explanations for the discrepancy of findings from epidemiologic studies and AMR reports. METHODS: We evaluated three hypotheses as possible explanations for the inconsistency between the AMR-based calculations and the findings from published epidemiologic studies: (i) differences in exposure characteristics of Australian vehicle mechanics versus vehicle mechanics in North America and Europe, (ii) limitations of the AMR data and (iii) errors in the risk calculations based on AMR data. We reviewed available exposure information specific to Australian vehicle mechanics and AMR data, obtained from the Australian National Occupational Health and Safety Commission, for this evaluation. RESULTS: We did not identify differences in workplace exposures, processes or fibre type among Australian vehicle mechanics compared to vehicle mechanics in other countries. Our analysis of primary AMR data identified several errors in exposure classification and in the assumptions used to calculate relative risk. CONCLUSIONS: Discrepancies between epidemiologic studies and AMR-based calculations cannot be explained by differences in exposure. These discrepancies are most likely attributable to inadequate occupational information and classification in the AMR from 1986 forward and to erroneous assumptions used to derive relative risk estimates for mesothelioma among Australian vehicle mechanics.     

Children's exposure assessment: a review of factors influencing Children's exposure, and the data available to characterize and assess that exposure

We review the factors influencing children's exposure to environmental contaminants and the data available to characterize and assess that exposure. Children's activity pattern data requirements are demonstrated in the context of the algorithms used to estimate exposure by inhalation, dermal contact, and ingestion. Currently, data on children's exposures and activities are insufficient to adequately assess multimedia exposures to environmental contaminants. As a result, regulators use a series of default assumptions and exposure factors when conducting exposure assessments. Data to reduce uncertainty in the assumptions and exposure estimates are needed to ensure chemicals are regulated appropriately to protect children's health. To improve the database, advancement in the following general areas of research is required: identification of appropriate age/developmental benchmarks for categorizing children in exposure assessment; development and improvement of methods for monitoring children's exposures and activities; collection of activity pattern data for children (especially young children) required to assess exposure by all routes; collection of data on concentrations of environmental contaminants, biomarkers, and transfer coefficients that can be used as inputs to aggregate exposure models.     

Population attributable fraction for lung cancer due to residential radon in Switzerland and Germany

Studies on miners as well as epidemiological studies in the general population show an increased lung cancer risk after exposure to radon and its progeny. The European pooled analysis of indoor radon studies estimates an excess relative risk of 8% (16% after correction for measurement uncertainties) per 100 Bq m(-3) indoor radon concentration. Here, we determine the population attributable fraction (PAF) for lung cancer due to residential radon based on this risk estimate for Switzerland and Germany. Based on regionally stratified radon data, the PAF was calculated following the World Health Organization concept of global burden of disease, compared to a realistic baseline radon concentration equal to the outdoor concentration. Lifetable approaches were used taking smoking and sex into account. Measurement error corrections were applied to both risk estimates and the radon distribution. In Switzerland, the average indoor radon concentration is 78 Bq m(-3), resulting in a PAF of 8.3%. Therefore, 169 male lung cancer deaths and 62 deaths in women can be attributed to residential radon per year. For Germany, the average indoor radon concentration is 49 Bq m(-3), corresponding to a PAF of 5.0% (1,422 male and 474 female deaths annually). In both countries, a large regional variation in the PAF was observed due to regional differences in radon concentrations and population structure. Both calculations show a strong dependency on the risk model used. Risk models based on miner studies result in higher PAF estimates than risk models based on indoor radon studies due to different assumptions regarding exposures received more than 35 years ago. The use of a non-zero baseline radon concentration also contributes to the lower PAF estimates reported here. Although the estimates of the population attributable fraction of residential radon presented here are lower than previously reported estimates, the risk is still one of the most widespread environmental hazards. Radon monitoring and radon reduction programs are therefore important issues for environmental public health management.     

Quantifying the disease impact of cigarette smoking with SAMMEC II software

Smoking-Attributable Mortality, Morbidity, and Economic Costs Software, Release II (SAMMEC II) has been developed for the Office on Smoking and Health, Public Health Service, to permit rapid calculation of deaths, years of potential life lost, direct health-care costs, indirect mortality costs, and disability costs associated with cigarette smoking. For the mortality-related measures, age-specific and age-adjusted rates are also calculated. The pivotal epidemiologic measure in these calculations is the smoking-attributable fraction, and attributal risk measure. A multiple-measure approach (attributable mortality and economic costs) to quantifying a health problem is termed "disease impact estimation." Previously, national and State-specific estimates of smoking-attributable mortality and economic costs were calculated using SAMMEC software, the predecessor of SAMMEC II. SAMMEC II is completely menu-driven and operates within the Lotus 1-2-3 software as a set of linked spreadsheets. SAMMEC II adapts national epidemiologic methods for use by State and local health departments. Increased exposure of public health professionals to disease impact estimation techniques, as demonstrated by SAMMEC II, will lead to improvements in both methodology and the quality of smoking-related health data. The primary purpose of SAMMEC II, however, is to provide State or locality-specific data on the health consequences of smoking to policymakers and public health professionals in these jurisdictions.     

Cost-effectiveness of dengue vaccination in ten endemic countries

Following publication of results from two phase-3 clinical trials in 10 countries or territories, endemic countries began licensing the first dengue vaccine in 2015. Using a published mathematical model, we evaluated the cost-effectiveness of dengue vaccination in populations similar to those at the trial sites in those same Latin American and Asian countries. Our main scenarios (30-year horizon, 80% coverage) entailed 3-dose routine vaccinations costing US$20/dose beginning at age 9, potentially supplemented by catch-up programs of 4- or 8-year cohorts. We obtained illness costs per case, dengue mortality, vaccine wastage, and vaccine administration costs from the literature. We estimated that routine vaccination would reduce yearly direct and indirect illness cost per capita by 22% (from US$10.51 to US$8.17) in the Latin American countries and by 23% (from US$5.78 to US$4.44) in the Asian countries. Using a health system perspective, the incremental cost-effectiveness ratio (ICER) averaged US$4,216/disability-adjusted life year (DALY) averted in the five Latin American countries (range: US$666/DALY in Puerto Rico to US$5,865/DALY in Mexico). In the five Asian countries, the ICER averaged US$3,751/DALY (range: US$1,935/DALY in Malaysia to US$5,101/DALY in the Philippines). From a health system perspective, the vaccine proved to be highly cost effective (ICER under one times the per capita GDP) in seven countries and cost effective (ICER 1–3 times the per capita GDP) in the remaining three countries. From a societal perspective, routine vaccination proved cost-saving in three countries. Including catch-up campaigns gave similar ICERs. Thus, this vaccine could have a favorable economic value in sites similar to those in the trials.     

Estimating the economic impact of secondhand smoke on the health of a community

PURPOSE: This study provides a model to estimate the health-related costs of secondhand smoke exposure at a community level. MODEL DEVELOPMENT: Costs of secondhand smoke-related mortality and morbidity were estimated using national attributable risk values for diseases that are causally related to secondhand smoke exposure for adults and children. Estimated costs included ambulatory care costs, hospital inpatient costs, and loss of life costs based on vital statistics, hospital discharge data, and census data. APPLICATION OF THE MODEL: The model was used to estimate health-related costs estimates of secondhand smoke exposure for Marion County, Indiana. Attributable risk values were applied to the number of deaths and hospital discharges to determine the number of individuals impacted by secondhand smoke exposure. RESULTS: The overall cost of health care and premature loss of life attributed to secondhand smoke for the study county was estimated to be $53.9 million in 2000-$10.5 million in health care costs and $20.3 million in loss of life for children compared with $6.2 million in health care costs and $16.9 million in loss of life for adults. This amounted to $62.68 per capita. CONCLUSIONS: This method may be replicated in other counties to provide data needed to educate the public and community leaders about the health effects and costs of secondhand smoke exposure.     

Two methods of estimating health costs linked to alcoholism in France (with a note on social costs)

The health costs of alcohol-related problems in France were estimated using two cost evaluation approaches: (1) estimate based on the proportion of cases attributable to alcohol abuse (the alcohol abuse factor); (2) estimate based on prevalence of alcohol abuse for in- and out-patients. For a 10% prevalence of alcohol abuse in the general population, the minimum cost in 1996 was about US$ 2300 million; for a prevalence of 15% it was US$ 2700 million. This cost concerns the health disorders that are linked directly or indirectly to alcohol abuse. It did not allow for injuries from accidents caused by alcohol intoxication and undervalued the cost of out-patient care. Based on the prevalence of alcohol-related disorders seen at hospitals, a percentage of the total in-patient and out-patient costs due to effects of alcohol could be estimated. However, this did not permit an estimate of the cost of care in which alcohol abuse was a risk factor only. Based on the available data showing that between 3% and 10% of inpatients have a directly alcohol-related condition, estimates of in-patient treatment costs varied from US$ 1300 to 2100 million. Among adult out-patients, 20% present with a disorder in which alcohol is a factor or suffer from an alcohol-related illness, which corresponds to a cost of about US$ 1600 million. Thus, these methods yield minimum year's cost estimated between US$ 2500 and 3300 million. These costs are high, compared to the low level of financing for the specialized facilities offering treatment to people in difficulty due to alcohol excess, which was US$ 23 million in that year. As regards social and total costs, estimates from four Western countries have found that about 75% of the total costs of alcohol abuse was attributable to social harm, and 25% to medical costs. Applying this ratio to the French data gives an estimated total cost to French society of about US$ 13 200 million, i.e. 1.04% of the gross national product.     

Epidemiologische Erforschung und ökonomische Bewertung gesundheitlicher Umweltrisiken

In environmental health research, methods for quantitative analysis of human population studies data are gaining importance. In recent years, it has been realized that they can also provide an important link to the economic view on environmental health effects. In this review, fundamental concepts and methods from environmental epidemiology and health economics are presented and it is shown how they can be linked in order to support environmental policy decisions. In addition, the characteristics of environmental epidemiology and the role of epidemiologic studies in risk assessment are discussed. From the economic point of view, cost-of-illness studies and cost effectiveness studies are the main approaches, and we have placed special focus on methods of monetary valuation of health effects that are generally proposed in the environmental context. Two conceptually differing strategies to combine epidemiologic and economic evidence are presented: the environmental attributable fraction model as a top-down approach and the impact pathway approach which follows a bottom-up analysis strategy. Finally, two examples are used to illustrate the application of these concepts and methods: health risks caused by fine particle air pollution and their costs, and the cost-effectiveness of radon exposure reduction policies.     

Quantifying children's aggregate (dietary and residential) exposure and dose to permethrin: application and evaluation of EPA's probabilistic SHEDS-Multimedia model

Reliable, evaluated human exposure and dose models are important for understanding the health risks from chemicals. A case study focusing on permethrin was conducted because of this insecticide's widespread use and potential health effects. SHEDS-Multimedia was applied to estimate US population permethrin exposures for 3- to 5-year-old children from residential, dietary, and combined exposure routes, using available dietary consumption data, food residue data, residential concentrations, and exposure factors. Sensitivity and uncertainty analyses were conducted to identify key factors, pathways, and research needs. Model evaluation was conducted using duplicate diet data and biomonitoring data from multiple field studies, and comparison to other models. Key exposure variables were consumption of spinach, lettuce, and cabbage; surface-to-skin transfer efficiency; hand mouthing frequency; fraction of hand mouthed; saliva removal efficiency; fraction of house treated; and usage frequency. For children in households using residential permethrin, the non-dietary exposure route was most important, and when all households were included, dietary exposure dominated. SHEDS-Multimedia model estimates compared well to real-world measurements data; this exposure assessment tool can enhance human health risk assessments and inform children's health research. The case study provides insights into children's aggregate exposures to permethrin and lays the foundation for a future cumulative pyrethroid pesticides risk assessment.     

The economic costs of child sexual abuse in Canada: a preliminary analysis

This paper describes a study of the economic costs attributable to child sexual abuse in Canada for the 1997-98 fiscal year. The preliminary cost estimate of child sexual abuse in Canada exceeds $3.6 billion dollars annually. This includes both public and private costs across four policy areas: health, social/public services, justice, and education/research and employment. These estimates have important policy implications in the area of child sexual abuse. The effectiveness of remedies, and options for new initiatives, policies and programs can be further evaluated using these economic calculations.     

Infant exposure to chemicals in breast milk in the United States: what we need to learn from a breast milk monitoring program

The presence of environmental chemicals in breast milk has gained increased attention from regulatory agencies and groups advocating women's and children's health. As the published literature on chemicals in breast milk has grown, there remains a paucity of data on parameters related to infant exposure via breast-feeding, particularly those with a time-dependent nature. This information is necessary for performing exposure assessments without heavy reliance on default assumptions. Although most experts agree that, except in unusual situations, breast-feeding is the preferred nutrition, a better understanding of an infant's level of exposure to environmental chemicals is essential, particularly in the United States where information is sparse. In this paper, we review extant data on two parameters needed to conduct realistic exposure assessments for breast-fed infants: a) levels of chemicals in human milk in the United States (and trends for dioxins/furans); and b) elimination kinetics (depuration) of chemicals from the mother during breast-feeding. The limitations of the existing data restrict our ability to predict infant body burdens of these chemicals from breast-feeding. Although the data indicate a decrease in breast milk dioxin toxic equivalents over time for several countries, the results for the United States are ambiguous. Whereas available information supports the inclusion of depuration when estimating exposures from breast-feeding, the data do not support selection of a specific rate of depuration. A program of breast milk monitoring would serve to provide the information needed to assess infant exposures during breast-feeding and develop scientifically sound information on benefits and risks of breast-feeding in the United States.     

Environmental lead exposure: a public health problem of global dimensions

Lead is the most abundant of the heavy metals in the Earth's crust. It has been used since prehistoric times, and has become widely distributed and mobilized in the environment. Exposure to and uptake of this non-essential element have consequently increased. Both occupational and environmental exposures to lead remain a serious problem in many developing and industrializing countries, as well as in some developed countries. In most developed countries, however, introduction of lead into the human environment has decreased in recent years, largely due to public health campaigns and a decline in its commercial usage, particularly in petrol. Acute lead poisoning has become rare in such countries, but chronic exposure to low levels of the metal is still a public health issue, especially among some minorities and socioeconomically disadvantaged groups. In developing countries, awareness of the public health impact of exposure to lead is growing but relatively few of these countries have introduced policies and regulations for significantly combating the problem. This article reviews the nature and importance of environmental exposure to lead in developing and developed countries, outlining past actions, and indicating requirements for future policy responses and interventions.     

Public health impact of extremely low-frequency electromagnetic fields

INTRODUCTION: The association between exposure to extremely low-frequency electric and magnetic fields (ELF) and childhood leukemia has led to the classification of magnetic fields by the International Agency for Research on Cancer as a "possible human carcinogen." This association is regarded as the critical effect in risk assessment. Creating effective policy in light of widespread exposure and the undisputed value of safe, reliable, and economic electricity to society is difficult and requires estimates of the potential public health impact and associated uncertainties. OBJECTIVES: Although a causal relationship between magnetic fields and childhood leukemia has not been established, we present estimates of the possible pubic health impact using attributable fractions to provide a potentially useful input into policy analysis under different scenarios. METHODS: Using ELF exposure distributions from various countries and dose-response functions from two pooled analyses, we calculate country-specific and worldwide estimates of attributable fractions (AFs) and attributable cases. RESULTS: Even given a wide range of assumptions, we find that the AF remains < 10%, with point estimates ranging from < 1% to about 4%. For small countries with low exposure, the number of attributable cases is less than one extra case per year. Worldwide the range is from 100 to 2,400 cases possibly attributable to ELF exposure. CONCLUSION: The fraction of childhood leukemia cases possibly attributable to ELF exposure across the globe appears to be small. There remain, however, a number of uncertainties in these AF estimates, particularly in the exposure distributions.