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Lead (Pb) exposures from soil and dust ingestion contribute to children's blood lead levels (BLLs) in the United States. The U.S. Environmental Protection Agency (EPA)'s Strategy to Reduce Lead Exposures and Disparities in U.S. Communities and the Federal Action Plan to Reduce Childhood Lead Exposure describe multi-pronged collaborative approaches. These include reducing multi-media lead exposures nationally using analytical tools such as EPA's Stochastic Human Exposure and Dose Simulation model for lead [SHEDS-Pb; formerly known as SHEDS-IEUBK (Integrated Exposure Uptake Biokinetic model)], which was initially developed and applied with a focus on children's drinking water exposures. In this study we applied SHEDS-Pb to determine what residential soil Pb and dust Pb concentrations (individually and their sum) can keep BLLs of potentially exposed young children in the general U.S. population below specified values, considering aggregate exposures from water, soil, dust, food, and air. We considered two age groups (1 to <2 years and 2 to <6 years), two BLL values (5 μg/dL and 3.5 μg/dL), and two population percentiles (95 th and 97.5 th ). Sensitivity analyses were conducted using several alternative model inputs and data sets, yielding 15 scenarios summarized in the paper. Of those scenarios, we focused on ones with the most recent science and available data. Modeled soil Pb concentrations by age group, population percentile and reference BLL scenarios for the focus scenarios ranged from 70 ppm to 220 ppm; and modeled dust Pb concentrations ranged from 110 ppm to 240 ppm. These results are consistent with current soil and dust Pb concentrations in the U.S. general population and are lower than most of the current U.S. Federal standards. Estimated BLLs compared well with measured BLLs from CDC's NHANES 2009-2016 (0-27 % relative error for focus scenarios). This analysis can be used to inform EPA and other federal Pb efforts., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier B.V.)

Background: Despite great progress in reducing environmental lead (Pb) levels, many children in the United States are still being exposed., Objective: Our aim was to develop a generalizable approach for systematically identifying, verifying, and analyzing locations with high prevalence of children's elevated blood Pb levels (EBLLs) and to assess available Pb models/indices as surrogates, using a Michigan case study., Methods: We obtained ∼ 1.9  million BLL test results of children < 6  years of age in Michigan from 2006-2016; we then evaluated them for data representativeness by comparing two percentage EBLL (%EBLL) rates (number of children tested with EBLL divided by both number of children tested and total population). We analyzed %EBLLs across census tracts over three time periods and between two EBLL reference values ( ≥ 5 vs. ≥ 10 μ g / dL ) to evaluate consistency. Locations with high %EBLLs were identified by a top 20 percentile method and a Getis-Ord Gi* geospatial cluster "hotspot" analysis. For the locations identified, we analyzed convergences with three available Pb exposure models/indices based on old housing and sociodemographics., Results: Analyses of 2014-2016 %EBLL data identified 11 Michigan locations via cluster analysis and 80 additional locations via the top 20 percentile method and their associated census tracts. Data representativeness and consistency were supported by a 0.93 correlation coefficient between the two EBLL rates over 11 y, and a Kappa score of ∼ 0.8 of %EBLL hotspots across the time periods (2014-2016) and reference values. Many EBLL hotspot locations converge with current Pb exposure models/indices; others diverge, suggesting additional Pb sources for targeted interventions., Discussion: This analysis confirmed known Pb hotspot locations and revealed new ones at a finer geographic resolution than previously available, using advanced geospatial statistical methods and mapping/visualization. It also assessed the utility of surrogates in the absence of blood Pb data. This approach could be applied to other states to inform Pb mitigation and prevention efforts. https://doi.org/10.1289/EHP9705.

1,4-Dioxane is a persistent and mobile organic chemical that has been found by the United States Environmental Protection Agency (USEPA) to be an unreasonable risk to human health in some occupational contexts. 1,4-Dioxane is released into the environment as industrial waste and occurs in some personal-care products as an unintended byproduct. However, limited exposure assessments have been conducted outside of an occupational context. In this study, the USEPA simulation modeling tool, Stochastic Human Exposure and Dose Simulator-High Throughput (SHEDS-HT), was adapted to estimate the exposure and chemical mass released down the drain (DTD) from drinking water consumption and product use. 1,4-Dioxane concentrations measured in drinking water and consumer products were used by SHEDS-HT to evaluate and compare the contributions of these sources to exposure and mass released DTD. Modeling results showed that compared to people whose daily per capita exposure came from only products (2.29 × 10 -7 to 2.92 × 10 -7 mg/kg/day), people exposed to both contaminated water and product use had higher per capita median exposures (1.90 × 10 -6 to 4.27 × 10 -6 mg/kg/day), with exposure mass primarily attributable to water consumption (75-91%). Last, we demonstrate through simulation that while a potential regulatory action could broadly reduce DTD release, the proportional reduction in exposure would be most significant for people with no or low water contamination.

Environmental lead (Pb) contamination is a persistent public health issue that prominently impacts communities across the United States. Multimedia Pb exposure assessments are utilized to provide a holistic evaluation of Pb exposure and inform the development of programs and regulations that are protective of human health. To conduct multimedia exposure assessments, robust, media-specific environmental Pb concentration data are necessary. To support this effort, systematic review and meta-analysis methods were used to conduct a comprehensive synthesis of research measuring Pb in multiple environmental media (soil, dust, water, food, and air) over a 20-year period within the United States. The breadth of the resulting database allowed for the evaluation of sample characteristics that can serve as indicators of environmental Pb contamination. Random effects models run on literature and national survey datasets generated overall mean estimates of Pb concentrations that can be used for multimedia Pb exposure modeling for general and high-exposure-risk populations. Results from our study highlighted several important trends: 1) The mean estimate of Pb in residential soils is three times higher for urbanized areas than non-urbanized areas; 2) The mean estimate of Pb in produce reported in the literature is approximately three orders of magnitude greater than commercially-sourced raw produce monitored in national surveys; 3) The mean estimate of Pb in soils from shooting ranges is two times greater than non-residential Pb contaminated Superfund sites reported in the literature; 4) Research reporting environmental Pb concentrations for school and daycare sites is very limited; 5) Inconsistent sample collection and reporting of results limited synthesis efforts; and 6) The U.S. EPA's Air Quality System was the most robust, publicly available national survey resource. Results from these analyses will inform future multimedia Pb exposure assessments and be useful in prioritizing future research and program development., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

Association rule mining (ARM) has been widely used to identify associations between various entities in many fields. Although some studies have utilized it to analyze the relationship between chemicals and human health effects, fewer have used this technique to identify and quantify associations between environmental and social stressors. Socio-demographic variables were generated based on U.S. Census tract-level income, race/ethnicity population percentage, education level, and age information from the 2010-2014, 5-Year Summary files in the American Community Survey (ACS) database, and chemical variables were generated by utilizing the 2011 National-Scale Air Toxics Assessment (NATA) census tract-level air pollutant exposure concentration data. Six mobile- and industrial-source pollutants were chosen for analysis, including acetaldehyde, benzene, cyanide, particulate matter components of diesel engine emissions (namely, diesel PM), toluene, and 1,3-butadiene. ARM was then applied to quantify and visualize the associations between the chemical and socio-demographic variables. Census tracts with a high percentage of racial/ethnic minorities and populations with low income tended to have higher estimated chemical exposure concentrations (fourth quartile), especially for diesel PM, 1,3-butadiene, and toluene. In contrast, census tracts with an average population age of 40-50 years, a low percentage of racial/ethnic minorities, and moderate-income levels were more likely to have lower estimated chemical exposure concentrations (first quartile). Unsupervised data mining methods can be used to evaluate potential associations between environmental inequalities and social disparities, while providing support in public health decision-making contexts.

Drugs for neglected tropical diseases (NTD) are being excessively priced in the United States. Benznidazole, the first-line drug for Chagas disease, may become approved by the Food and Drug Administration (FDA) and manufactured by a private company in the US, thus placing it at risk of similar pricing. Chagas disease is an NTD caused by Trypanosoma cruzi; it is endemic to Latin America, infecting 8 million individuals. Human migration has changed the epidemiology causing nonendemic countries to face increased challenges in diagnosing and managing patients with Chagas disease. Only 2 drugs exist with proven efficacy: benznidazole and nifurtimox. Benznidazole has historically faced supply problems and drug shortages, limiting accessibility. In the US, it is currently only available under an investigational new drug (IND) protocol from the CDC and is provided free of charge to patients. However, 2 companies have stated that they intend to submit a New Drug Application (NDA) for FDA approval. Based on recent history of companies acquiring licensing rights for NTD drugs in the US with limited availability, it is likely that benznidazole will become excessively priced by the manufacturer-paradoxically making it less accessible. However, if the companies can be taken at their word, there may be reason for optimism.

Chagas disease is caused by the protozoan Trypanosoma cruzi. This parasite is transmitted to humans mainly through the faeces of infected triatomine "kissing" bugs, by blood transfusions or organ donation from infected donors, and can be transmitted from mother to child. This disease is endemic in the Americas, where Bolivia has up to 28.8% prevalence in general population. Increased migration to Europe has made it emerge in countries where it was previously unknown, being Spain the second country in number of patients after the United States. T. cruzi is an organism with a rich genetic diversity, what has been grouped into six discrete typing units (DTUs). Some authors have linked these DTUs either to specific geographical distribution or to the different clinical presentations. Nevertheless little is known about its distribution in migrant populations. Our aim was to describe the T. cruzi strains isolated from a population of chronically infected Bolivian patients attending our clinic in Madrid. Thirty-three consecutive patients meeting this condition were selected for the study. Molecular characterization was performed by an algorithm that combines PCR of the intergenic region of the mini exon-gene, the 24Sα and 18S regions of rDNA and the variable region of the satellite DNA. A descriptive analysis was performed and associations between epidemiological/clinical data and the different DTUs were tested. Twenty-seven out of thirty-three patients had their DTU detected. Mean age was 36 years (IQR 31-43.3) and 23 were women (76.7%). The median time since arrival to Spain was 60 months (IQR 43-81). The most common DTU were TcV, TcIV and TcI. Four patients had cardiac involvement: 2 had TcV and 2 could not have their DTU determined. TcIII was not isolated from any patient. DTUs distribution in migrant population seems to be similar to that observed in the patients' countries of origin., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In light of the massive uncertainty with both the federal government in general and health policy priorities specifically, it is probably constructive to focus on the things we know for sure. In Medicare Part B reimbursement, the SGR system is fundamentally flawed, and must be replaced. All of Congress has recognized this fact, and there is legislation in the House that would move the ball forward on SGR repeal and replacement. Likewise, coordinated care models like ACOs offer a logical process for achieving a triple aim: improving individual health care, improving population health, and promoting cost efficiency in health care. Hopefully, policy makers in Washington will recognize and act on these truths as well.

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.

Background: Diabetic retinopathy is the leading cause of preventable blindness in adults. Project I See in NC was begun to determine whether access to eye screening for Medicaid recipients and uninsured patients with diabetes in North Carolina could be improved., Methods: We targeted Medicaid recipients and uninsured adults with diabetes for screening in 2 Community Care of North Carolina Networks. Screenings were performed in primary care settings throughout 6 counties in the Northwest Community Care Network and 6 counties in Access III of Community Care of the Lower Cape Fear. Patients were screened using a high-resolution digital retinal camera with images read at a centralized reading center at Wake Forest School of Medicine., Results: A total of 1,688 patients were screened from October 2005 through September 2007. Nearly 15% (282) were found to have mild, nonproliferative-to-proliferative retinopathy, while the majority of patients had no evidence of diabetic retinopathy. Nearly 12% (196) required referral to an ophthalmologist, with 5% (86) requiring urgent referral for potentially sight-threatening retinopathy., Limitations: We were not able to confirm which patients kept their ophthalmologic appointments; however, we are currently analyzing data from the Medicaid patients in our study who required ophthalmologic referral., Conclusions: Remote digital retinal screening for diabetic retinopathy is feasible in primary care settings in both urban and rural areas of North Carolina, and it may prove to be an effective means of reaching more patients who require annual screening examinations.

A new generation of scientific tools has emerged to rapidly measure signals from cells, tissues, and organisms following exposure to chemicals. High-visibility efforts to apply these tools for efficient toxicity testing raise important research questions in exposure science. As vast quantities of data from high-throughput screening (HTS) in vitro toxicity assays become available, this new toxicity information must be translated to assess potential risks to human health from environmental exposures. Exposure information is required to link information on potential toxicity of environmental contaminants to real-world health outcomes. In the immediate term, tools are required to characterize and classify thousands of environmental chemicals in a rapid and efficient manner to prioritize testing and assess potential for risk to human health. Rapid risk assessment requires prioritization based on both hazard and exposure dimensions of the problem. To address these immediate needs within the context of longer term objectives for chemical evaluation and risk management, a translation framework is presented for incorporating toxicity and exposure information to inform public health decisions at both the individual and population levels. Examples of required exposure science contributions are presented with a focus on early advances in tools for modeling important links across the source-to-outcome paradigm. ExpoCast, a new U.S. Environmental Protection Agency (EPA) program aimed at developing novel approaches and metrics to screen and evaluate chemicals based on the potential for biologically relevant human exposures is introduced. The goal of ExpoCast is to advance characterization of exposure required to translate findings in computational toxicology to information that can be directly used to support exposure and risk assessment for decision making and improved public health.

Assessments of occupational exposures to chemicals are generally based upon the practice of compliance testing in which the probability of compliance is related to the exceedance [gamma, the likelihood that any measurement would exceed an occupational exposure limit (OEL)] and the number of measurements obtained. On the other hand, workers' chronic health risks generally depend upon cumulative lifetime exposures which are not directly related to the probability of compliance. In this paper we define the probability of "overexposure" (theta) as the likelihood that individual risk (a function of cumulative exposure) exceeds the risk inherent in the OEL (a function of the OEL and duration of exposure). We regard theta as a relevant measure of individual risk for chemicals, such as carcinogens, which produce chronic effects after long-term exposures but not necessarily for acutely-toxic substances which can produce effects relatively quickly. We apply a random-effects model to data from 179 groups of workers, exposed to a variety of chemical agents, and obtain parameter estimates for the group mean exposure and the within- and between-worker components of variance. These estimates are then combined with OELs to generate estimates of gamma and theta. We show that compliance testing can significantly underestimate the health risk when sample sizes are small. That is, there can be large probabilities of compliance with typical sample sizes, despite the fact that large proportions of the working population have individual risks greater than the risk inherent in the OEL. We demonstrate further that, because the relationship between theta and gamma depends upon the within- and between-worker components of variance, it cannot be assumed a priori that exceedance is a conservative surrogate for overexposure. Thus, we conclude that assessment practices which focus upon either compliance or exceedance are problematic and recommend that employers evaluate exposures relative to the probabilities of overexposure.

Objective: To assess from the perspectives of a government delivery system and patients, the cost-effectiveness of the 45-degrees retinal camera compared to the standard ophthalmologist's exam and an ophthalmic exam by a physician's assistant or nurse practitioner technician, for detecting nonproliferative and proliferative diabetic retinopathy., Research Design and Methods: Comparison of 45-degrees fundus photographs with and without pharmacological pupil dilation taken by technicians and interpreted by experts, direct and indirect ophthalmoscopy by ophthalmologists, and direct ophthalmoscopy by technicians with seven-field stereoscopic fundus photography (reference standard). Costs were estimated from market prices and actual resource use. The study included 352 patients attending outpatient diabetes and general-medicine clinics at VA and DOD facilities., Results: Medical system costs per true positive were: 45-degrees photos with dilation, $295; 45-degrees photos without dilation, $378; ophthalmologist, $390; and technician, $794. Patient costs per true positive were: 45-degrees photos with dilation, $139; 45-degrees photos without dilation, $171; ophthalmologist, $306; and technician, $1009. Cost-effectiveness is sensitive to program size due to high fixed cost of the camera methods but not to prevalence. Cost-effectiveness of the technician exam is strongly affected by its sensitivity., Conclusions: Primary-care screening with retinal photographs through pharmacologically dilated pupils for diabetic retinopathy is an appropriate and cost-effective alternative to screening by an ophthalmologist in this setting. Ophthalmologists are scarce, primary-care physicians are extremely busy, and large clinics allow fixed equipment costs to be spread across many patients.

In a general medical clinic setting, 880 patients were screened for depression by using the Diagnostic Interview Schedule version of the DSM-III and the Zung Self-Rating Depression Scale (SDS), as well as the Zung Self-Rating Anxiety Scale (SAS). Based on a morbidity cutoff index of 50 on the SDS and a positive DIS for depression, 112 patients (13%) were found to have a depressive disorder. The SDS showed a 97% sensitivity, a 63% specificity, and an 82% correct classification of depressed and nondepressed control patients. Based on the SDS results and SAS results when anxiety was considered present at a moderate severity level, the comorbidity of anxiety and depression was 67%. Depressed patients were followed for 1 year during which time they were retested with the SDS and SAS at five time points (6 weeks and quarterly). Fifty-one patients who met the criterion of a decrease of greater than or equal to 12 points in the SDS index were assigned to the improved group, 23 who met the criterion of an increase of greater than or equal to 12 points were assigned to the worse group, and 36 patients were assigned to the no-change group. Depressed patients who improved showed a significant decrease in anxiety based on SAS change scores; depressed patients who worsened showed a significant increase in their anxiety index. The decrease in the anxiety index of patients in the no-change group was not statistically significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Dramatic increases in mortality from multiple myeloma have been reported in the United States and the United Kingdom over the past three decades. To assess what fraction of this increase, if any, might be attributable to a change in the incidence of this disease, we examined the incidence of multiple myeloma during 1950 to 1979 in Malmö, Sweden, a city chosen because of its medical community's longstanding interest in this disease. The average annual incidence rates per 100,000 population were 4.9 for males and 3.7 for females (adjusted to the European age-standardized population). These rates are among the highest in the world. Unlike secular trends for myeloma in the United States and the United Kingdom, where large increases in mortality rates have been reported, the rates in Malmö have increased only slightly, and the increase was restricted to males, suggesting the possibility of environmental causes. We suggest that the rates in Malmö may represent the asymptote of myeloma's incidence that will be approached in other white populations as case ascertainment among them becomes complete.

In the study reported here, medical residents were surveyed to determine their patterns of educational indebtedness, the effects of debt on their decisions about training and career, the frequency with which they begin making loan payments during training, the extent to which they moonlight and the reasons for doing so, and their opinions about the effects of moonlighting on house staff training. A total of 223 residents from four residency programs were surveyed; 181 responded. Most (86 percent) had educational debt (mean = $20,500), and more than half of those with debt were making loan payments. Forty percent of the residents moonlighted, and moonlighting was related to the presence of educational debt, monthly loan payments, and number of dependents.

Mortality and morbidity rates for childhood leukemia are examined with reference to time trends and racial differences. Prior to 1964, white and nonwhite children had very different acute lymphocytic leukemia (ALL) mortality rates. With the advent of successful chemotherapy, the mortality rate of ALL in white children has decreased resulting in virtually no racial differences in ALL mortality. The reasons for a stable ALL mortality rate in nonwhite children despite successful chemotherapy include poor access to health care, undefined socioeconomic factors and a biologically different type of ALL occurring in nonwhite children. Recent data from two cancer surveys (1969-1971, 1973-1976) reveal that nonwhite children have a lower incidence of ALL than white children. Underreporting in the nonwhite children could partly account for the difference, but other contributing factors might include a genetic predisposition, undefined socioeconomic influences, and perhaps, a viral agent. Further studies of the factors contributing to racial differences in ALL incidence and mortality are needed.

A series of outcome indicators was proposed for assessing the curative aspects of health care using several diseases for which evidence suggested that death was largely avoidable provided that appropriate medical treatment could be given in time. International data were examined for those causes for which data were readily available. Time trends in mortality were compared for each of these conditions for six countries that had experienced appreciable growth in health services during 1950-80. Mortality from the heterogeneous "avoidable" causes had declined faster than mortality from all other causes in each of the six countries. Despite problems of diagnosis, reporting, and classification of diseases that may have existed among countries, making international comparisons of absolute mortality difficult, the trends of declining mortality were similar, lending credibility to the use of these causes of mortality as indices of health care within countries. Changes within countries may also have been attributable to changes in social, environmental, genetic, and diagnostic factors, which were not examined. Nevertheless, the consistency in mortality trends for this group of "amenable" diseases suggested that improvements in medical care were a factor in their rapid decline.