Mining and Environmental Health Disparities in Native American Communities

Geographic and dietary differences of urinary uranium levels in the Strong Heart Family Study

BACKGROUND

American Indian (AI) communities are affected by uranium exposure from abandoned mines and naturally contaminated drinking water. Few studies have evaluated geographical differences across AI communities and the role of dietary exposures.

OBJECTIVE

We evaluated differences in urinary uranium levels by diet and geographical area among AI participants from the Northern Plains, the Southern Plains, and the Southwest enrolled in the Strong Heart Family Study (SHFS).

METHODS

We used food frequency questionnaires to determine dietary sources related to urinary uranium levels for 1,682 SHFS participants in 2001-2003. We calculated adjusted geometric mean ratios (GMRs) of urinary uranium for an interquartile range (IQR) increase in self-reported food group consumption accounting for family clustering and adjusting for sociodemographic variables and other food groups. We determined the percentage of variability in urinary uranium explained by diet.

RESULTS

Median (IQR) urinary uranium levels were 0.027 (0.012, 0.057) μg/g creatinine. Urinary uranium levels were higher in Arizona (median 0.039 μg/g) and North Dakota and South Dakota (median 0.038 μg/g) and lower in Oklahoma (median 0.019 μg/g). The adjusted percent increase (95% confidence interval) of urinary uranium levels per IQR increase in reported food intake was 20% (5%, 36%) for organ meat, 11% (1%, 23%) for cereals, and 14% (1%, 29%) for alcoholic drinks. In analyses stratified by study center, the association with organ meat was specific to North Dakota and South Dakota participants. An IQR increase in consumption of fries and chips was inversely associated with urinary uranium levels -11% (-19%, -3%). Overall, we estimated that self-reported dietary exposures explained 1.71% of variability in urine uranium levels.

IMPACT

Our paper provides a novel assessment of self-reported food intake and urinary uranium levels in a cohort of American Indian participants. We identify foods (organ meat, cereals, and alcohol) positively associated with urinary uranium levels, find that organ meat consumption is only associated with urine uranium in North Dakota and South Dakota, and estimate that diet explains relatively little variation in total urinary uranium concentrations. Our findings contribute meaningful data toward a more comprehensive estimation of uranium exposure among Native American communities and support the need for high-quality assessments of water and dust uranium exposures in SHFS communities.

Serum metabolic changes link metal mixture exposures to vascular endothelial inflammation in residents living surrounding rivers near abandoned lead-zinc mines

Metal exposure is associated with vascular endothelial inflammation, an early pathological phenotype of atherosclerotic cardiovascular events. However, the underlying mechanism linking exposure, metabolic changes, and outcomes remains unclear. We aimed to investigate the metabolic changes underlying the associations of chronic exposure to metal mixtures with vascular endothelial inflammation. We recruited 960 adults aged 20-75 years from residential areas surrounding rivers near abandoned lead-zinc mine and classified them into river area and non-river area exposure groups. Urine levels of 25 metals, Framingham risk score (FRS), and serum concentrations of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), as biomarkers of vascular endothelial inflammation, were assessed. A "meet-in-the-middle" approach was applied to identify causal intermediate metabolites and metabolic pathways linking metal exposure to vascular endothelial inflammation in representative metabolic samples from 64 participants. Compared to the non-river area exposure group, the river area exposure group had significantly greater urine concentrations of chromium, copper, cadmium, and lead; lower urine concentrations of selenium; elevated FRS; and increased concentrations of ICAM-1 and VCAM-1. In total, 38 differentially abundant metabolites were identified between the river area and non-river area exposure groups. Among them, 25 metabolites were significantly associated with FRS, 8 metabolites with ICAM-1 expression, and 10 metabolites with VCAM-1 expression. Furthermore, fructose, ornithine, alpha-ketoglutaric acid, urea, and cytidine monophosphate, are potential mediators of the relationship between metal exposure and vascular endothelial inflammation. Additionally, the metabolic changes underlying these effects included changes in arginine and proline metabolism, pyrimidine metabolism, starch and sucrose metabolism, galactose metabolism, arginine biosynthesis, and alanine, aspartate, and glutamate metabolism, suggesting the disturbance of amino acid metabolism, the tricarboxylic acid cycle, nucleotide metabolism, and glycolysis. Overall, our results reveal biomechanisms that may link chronic exposure to multiple metals with vascular endothelial inflammation and elevated cardiovascular risk.

Association of Water Arsenic With Incident Diabetes in U.S. Adults: The Multi-Ethnic Study of Atherosclerosis and the Strong Heart Study

OBJECTIVE

We examined the association of arsenic in federally regulated community water systems (CWS) and unregulated private wells with type 2 diabetes (T2D) incidence in the Strong Heart Family Study (SHFS), a prospective study of American Indian communities, and the Multi-Ethnic Study of Atherosclerosis (MESA), a prospective study of racially and ethnically diverse urban U.S. communities.

RESEARCH DESIGN AND METHODS

We evaluated 1,791 participants from SHFS and 5,777 participants from MESA who had water arsenic estimates available and were free of T2D at baseline (2001-2003 and 2000-2002, respectively). Participants were followed for incident T2D until 2010 (SHFS cohort) or 2019 (MESA cohort). We used Cox proportional hazards mixed-effects models to account for clustering by family and residential zip code, with adjustment for sex, baseline age, BMI, smoking status, and education.

RESULTS

T2D incidence was 24.4 cases per 1,000 person-years (mean follow-up, 5.6 years) in SHFS and 11.2 per 1,000 person-years (mean follow-up, 14.0 years) in MESA. In a meta-analysis across the SHFS and MESA cohorts, the hazard ratio (95% CI) per doubling in CWS arsenic was 1.10 (1.02, 1.18). The corresponding hazard ratio was 1.09 (0.95, 1.26) in the SHFS group and 1.10 (1.01, 1.20) in the MESA group. The corresponding hazard ratio (95% CI) for arsenic in private wells and incident T2D in SHFS was 1.05 (0.95, 1.16). We observed statistical interaction and larger magnitude hazard ratios for participants with BMI <25 kg/m2 and female participants.

CONCLUSIONS

Low to moderate water arsenic levels (<10 µg/L) were associated with T2D incidence in the SHFS and MESA cohorts.

Seeking care across the US-Mexico border: The experiences of Latinx and Indigenous Mexican caregivers of children with asthma or respiratory distress

BACKGROUND

Many Latinx and Indigenous Mexican populations in the United States Southwest live in unincorporated communities in the US-Mexico borderlands called colonias. These environmental justice communities often lack basic infrastructure, including healthcare services, prompting many to seek services across the border. However, due to geopolitical factors more vulnerable caregivers are limited to utilize healthcare services in the US. This paper reports the experiences and healthcare decision-making of caregivers living in colonias in the US-Mexico border region who care for children with respiratory health conditions.

METHODS

This study was carried out from September to December 2020. Focus groups and interviews were conducted with Latinx and Indigenous Mexican caregivers of children with asthma or respiratory distress. Qualitative interviews elicited caregivers' perspectives on the environmental factors affecting children's chronic health conditions and use of healthcare services. The analysis employed the concept of structure vulnerability to theorize geography as a structural determinant of health for caregivers faced with making healthcare decisions for their suffering from respiratory health conditions. A survey was administered to collect basic sociodemographic information.

RESULTS

A total of 36 caregivers participated in the study. Structural factors including unincorporated community status and government inaction intersected with social determinants of health to prompt caregivers to cross the US-Mexico border to access healthcare services in Mexico for their children. Yet, more vulnerable caregivers (i.e., those without documentation status in the US) and their children, accessing healthcare services in the US was not an option limiting caregivers' ability to meet their children's healthcare needs. In such cases, geography acts as a structural determinant of health.

CONCLUSION

This study shows the importance of geography in health. Rural unincorporated colonias located in the borderlands are precariously located and lack basic critical infrastructure including healthcare access. Within such places, historically and socially marginalized populations become invisible, are subject to the health effects of environmental hazards, and are limited depending on their positionality and thus vulnerability to healthcare services.

Assessment of environmental pollution and human health risks of mine tailings in soil: after dam failure of the Córrego do Feijão Mine (in Brumadinho, Brazil)

The dam failure of the Córrego do Feijão Mine (CFM) located in Minas Gerais State, Brazil, killed at least 278 people. In addition, large extensions of aquatic and terrestrial ecosystems were destroyed, directly compromising the environmental and socioeconomic quality of the region. This study assessed the pollution and human health risks of soils impacted by the tailing spill of the CFM dam, along a sample perimeter of approximately 200 km. Based on potential ecological risk and pollution load indices, the enrichments of Cd, As, Hg, Cu, Pb and Ni in soils indicated that the Brumadinho, Mário Campos, Betim and São Joaquim de Bicas municipalities were the most affected areas by the broken dam. Restorative and reparative actions must be urgently carried out in these areas. For all contaminated areas, the children's group indicated an exacerbated propensity to the development of carcinogenic and non-carcinogenic diseases, mainly through the ingestion pathway. Toxicological risk assessments, including acute, chronic and genotoxic effects, on people living and working in mining areas should be a priority for public management and mining companies to ensure effective environmental measures that do not harm human health and well-being over time.

Contribution of arsenic and uranium in private wells and community water systems to urinary biomarkers in US adults: The Strong Heart Study and the Multi-Ethnic Study of Atherosclerosis

BACKGROUND

Chronic exposure to inorganic arsenic (As) and uranium (U) in the United States (US) occurs from unregulated private wells and federally regulated community water systems (CWSs). The contribution of water to total exposure is assumed to be low when water As and U concentrations are low.

OBJECTIVE

We examined the contribution of water As and U to urinary biomarkers in the Strong Heart Family Study (SHFS), a prospective study of American Indian communities, and the Multi-Ethnic Study of Atherosclerosis (MESA), a prospective study of racially/ethnically diverse urban U.S. communities.

METHODS

We assigned residential zip code-level estimates in CWSs (µg/L) and private wells (90th percentile probability of As >10 µg/L) to up to 1485 and 6722 participants with dietary information and urinary biomarkers in the SHFS (2001-2003) and MESA (2000-2002; 2010-2011), respectively. Urine As was estimated as the sum of inorganic and methylated species, and urine U was total uranium. We used linear mixed-effects models to account for participant clustering and removed the effect of dietary sources via regression adjustment.

RESULTS

The median (interquartile range) urine As was 5.32 (3.29, 8.53) and 6.32 (3.34, 12.48) µg/L for SHFS and MESA, respectively, and urine U was 0.037 (0.014, 0.071) and 0.007 (0.003, 0.018) µg/L. In a meta-analysis across both studies, urine As was 11% (95% CI: 3, 20%) higher and urine U was 35% (5, 73%) higher per twofold higher CWS As and U, respectively. In the SHFS, zip-code level factors such as private well and CWS As contributed 46% of variation in urine As, while in MESA, zip-code level factors, e.g., CWS As and U, contribute 30 and 49% of variation in urine As and U, respectively.

IMPACT STATEMENT

We found that water from unregulated private wells and regulated CWSs is a major contributor to urinary As and U (an estimated measure of internal dose) in both rural, American Indian populations and urban, racially/ethnically diverse populations nationwide, even at levels below the current regulatory standard. Our findings indicate that additional drinking water interventions, regulations, and policies can have a major impact on reducing total exposures to As and U, which are linked to adverse health effects even at low levels.

US drinking water quality: exposure risk profiles for seven legacy and emerging contaminants

BACKGROUND

Advances in drinking water infrastructure and treatment throughout the 20th and early 21st century dramatically improved water reliability and quality in the United States (US) and other parts of the world. However, numerous chemical contaminants from a range of anthropogenic and natural sources continue to pose chronic health concerns, even in countries with established drinking water regulations, such as the US.

OBJECTIVE/METHODS

In this review, we summarize exposure risk profiles and health effects for seven legacy and emerging drinking water contaminants or contaminant groups: arsenic, disinfection by-products, fracking-related substances, lead, nitrate, per- and polyfluorinated alkyl substances (PFAS) and uranium. We begin with an overview of US public water systems, and US and global drinking water regulation. We end with a summary of cross-cutting challenges that burden US drinking water systems: aging and deteriorated water infrastructure, vulnerabilities for children in school and childcare facilities, climate change, disparities in access to safe and reliable drinking water, uneven enforcement of drinking water standards, inadequate health assessments, large numbers of chemicals within a class, a preponderance of small water systems, and issues facing US Indigenous communities.

RESULTS

Research and data on US drinking water contamination show that exposure profiles, health risks, and water quality reliability issues vary widely across populations, geographically and by contaminant. Factors include water source, local and regional features, aging water infrastructure, industrial or commercial activities, and social determinants. Understanding the risk profiles of different drinking water contaminants is necessary for anticipating local and general problems, ascertaining the state of drinking water resources, and developing mitigation strategies.

IMPACT STATEMENT

Drinking water contamination is widespread, even in the US. Exposure risk profiles vary by contaminant. Understanding the risk profiles of different drinking water contaminants is necessary for anticipating local and general public health problems, ascertaining the state of drinking water resources, and developing mitigation strategies.

Sources of exposure to lead in Arctic and subarctic regions: a scoping review

Understanding lead exposure pathways is a priority because of its ubiquitous presence in the environment as well as the potential health risks. We aimed to identify potential lead sources and pathways of lead exposure, including long-range transport, and the magnitude of exposure in Arctic and subarctic communities. A scoping review strategy and screening approach was used to search literature from January 2000 to December 2020. A total of 228 academic and grey literature references were synthesised. The majority of these studies (54%) were from Canada. Indigenous people in Arctic and subarctic communities in Canada had higher levels of lead than the rest of Canada. The majority of studies in all Arctic countries reported at least some individuals above the level of concern. Lead levels were influenced by a number of factors including using lead ammunition to harvest traditional food and living in close proximity to mines. Lead levels in water, soil, and sediment were generally low. Literature showed the possibility of long-range transport via migratory birds. Household lead sources included lead-based paint, dust, or tap water. This literature review will help to inform management strategies for communities, researchers, and governments, with the aim of decreasing lead exposure in northern regions.

Preterm Birth and Metal Mixture Exposure among Pregnant Women from the Navajo Birth Cohort Study

BACKGROUND

Preterm birth (PTB), defined as birth before 37 wk gestation, is associated with hypertension, diabetes, inadequate prenatal care, unemployment or poverty, and metal exposure. Indigenous individuals are more likely to have maternal risk factors associated with PTB compared with other populations in the United States; however, the role of environmental metals on PTB among pregnant Indigenous women remains uncertain. Previous research identified associations between PTB and individual metals, but there is limited investigation on metal mixtures and this birth outcome.

OBJECTIVES

We used a mixtures analysis framework to investigate the association between metal mixtures and PTB among pregnant Indigenous women from the Navajo Birth Cohort Study (NBCS).

METHODS

Maternal urine and blood samples were collected at the time of study enrollment and analyzed for metals by inductively coupled plasma dynamic reaction cell mass spectrometry. Bayesian Profile Regression was used to identify subgroups (clusters) of individuals with similar patterns of coexposure and to model association with PTB.

RESULTS

Results indicated six subgroups of maternal participants with distinct exposure profiles, including one group with low exposure to all metals and one group with total arsenic, cadmium, lead, and uranium concentrations exceeding representative concentrations calculated from the National Health and Nutrition Examination Survey (NHANES). Compared with the reference group (i.e., the lowest exposure subgroup), the subgroup with the highest overall exposure had a relative risk of PTB of 2.9 times (95% credible interval: 1.1, 6.1). Exposures in this subgroup were also higher overall than NHANES median values for women 14-45 years of age.

DISCUSSION

Given the wide range of exposures and elevated PTB risk for the most exposed subgroups in a relatively small study, follow-up investigation is recommended to evaluate associations between metal mixture profiles and other birth outcomes and to test hypothesized mechanisms of action for PTB and oxidative stress caused by environmental metals. https://doi.org/10.1289/EHP10361.

Fine particulate matter composition in American Indian vs. Non-American Indian communities

BACKGROUND

Fine particulate matter (PM2.5) exposure is a known risk factor for numerous adverse health outcomes, with varying estimates of component-specific effects. Populations with compromised health conditions such as diabetes can be more sensitive to the health impacts of air pollution exposure. Recent trends in PM2.5 in primarily American Indian- (AI-) populated areas examined in previous work declined more gradually compared to the declines observed in the rest of the US. To further investigate components contributing to these findings, we compared trends in concentrations of six PM2.5 components in AI- vs. non-AI-populated counties over time (2000-2017) in the contiguous US.

METHODS

We implemented component-specific linear mixed models to estimate differences in annual county-level concentrations of sulfate, nitrate, ammonium, organic matter, black carbon, and mineral dust from well-validated surface PM2.5 models in AI- vs. non-AI-populated counties, using a multi-criteria approach to classify counties as AI- or non-AI-populated. Models adjusted for population density and median household income. We included interaction terms with calendar year to estimate whether concentration differences in AI- vs. non-AI-populated counties varied over time.

RESULTS

Our final analysis included 3108 counties, with 199 (6.4%) classified as AI-populated. On average across the study period, adjusted concentrations of all six PM2.5 components in AI-populated counties were significantly lower than in non-AI-populated counties. However, component-specific levels in AI- vs. non-AI-populated counties varied over time: sulfate and ammonium levels were significantly lower in AI- vs. non-AI-populated counties before 2011 but higher after 2011 and nitrate levels were consistently lower in AI-populated counties.

CONCLUSIONS

This study indicates time trend differences of specific components by AI-populated county type. Notably, decreases in sulfate and ammonium may contribute to steeper declines in total PM2.5 in non-AI vs. AI-populated counties. These findings provide potential directives for additional monitoring and regulations of key emissions sources impacting tribal lands.

Comparison of circulating and excreted metals and of autoimmunity between two Great Plains Tribal communities

Metals contaminants of the environment from mine waste have been implicated as contributing agents in autoimmune disease. The current study compares metals and autoimmunity in two Tribal communities residing in the Black Hills and the Bighorn Mountains geographical regions that are scattered with extant hard rock mines. With documented drinking water contamination in both communities, in vivo levels of more than half of the measured serum and urine metals differed between the two communities and were substantially different from their national median values. Serum autoantibodies associated with systemic autoimmune disease were rare or at low-level, but antibodies to denatured (single-stranded) DNA and thyroid-specific autoantibodies were commonly elevated, especially in women. A three-tier statistical modeling process was carried out to examine individual metals exposure as predictors of autoantibody levels. For the most part only weak positive associations between individual metals and systemic autoantibodies were found, although univariate quantile regression analysis showed positive statistical associations of serum lead and antimony with anti-chromatin and anti-histone autoantibodies. Using age and gender-adjusted multivariable statistical models, metals did not predict anti-thyroglobulin or -thyroid peroxidase significantly and metals were generally negative predictors of the other autoantibodies. Overall these results suggest that elevated levels of environmental metals and metalloids in these communities may result in suppression of autoantibodies associated with systemic autoimmune disease.

Race, Racism, and Respiratory Health

The study and practice of pulmonary medicine have been profoundly influenced by race theory, which was ascendant at the time of key developments within the specialty. We explore how, as a social determinant of health, race remains a powerful driver of present-day health disparities in respiratory diseases. Both legacy and contemporary inequities are identified through Dr DR Williams's model of cultural, structural, and interpersonal racism.

Structural and Social Determinants of Inequitable Environmental Exposures in the United States

American Indian (AI)/Alaskan Natives, African Americans, and Latino Americans have disproportionally high exposure to harmful environmental conditions as a consequence of unjust laws and policies, systemic racism, residential segregation, and discrimination. In this review, we draw connections between historical policies and social movements in the United States' history that have been rooted in racism and classism, leading to social isolation and marginalization of AIs, African Americans, and Latino Americans. We then discuss the structural factors that stem from the aforementioned inequities and that contribute to the inequitable distribution of environmental hazards.

Metal mixtures and DNA methylation measures of biological aging in American Indian populations

INTRODUCTION

Native American communities suffer disproportionately from elevated metal exposures and increased risk for cardiovascular diseases and diabetes. DNA methylation is a sensitive biomarker of aging-related processes and novel epigenetic-based "clocks" can be used to estimate accelerated biological aging that may underlie increased risk. Metals alter DNA methylation, yet little is known about their individual and combined impact on epigenetic age acceleration. Our objective was to investigate the associations of metals on several DNA methylation-based aging measures in the Strong Heart Study (SHS) cohort.

METHODS

Blood DNA methylation data from 2,301 SHS participants was used to calculate age acceleration of epigenetic clocks (PhenoAge, GrimAge, DunedinPACE, Hannum, Horvath). Urinary metals [arsenic (As), cadmium (Cd), tungsten (W), zinc (Zn), selenium (Se), molybdenum (Mo)] were creatinine-adjusted and categorized into quartiles. We examined associations of individual metals through linear regression models and used Bayesian Kernel Machine Regression (BKMR) for the impact of the total metal mixture on epigenetic age acceleration.

RESULTS

The mixture of nonessential metals (W, As, Cd) was associated with greater GrimAge acceleration and DunedinPACE, while the essential metal mixture (Se, Zn, Mo) was associated with lower epigenetic age acceleration. Cd was associated with increased epigenetic age acceleration across all clocks and BKMR analysis suggested nonlinear associations between Se and DunedinPACE, GrimAge, and PhenoAge acceleration. No interactions between individual metals were observed. The associations between Cd, Zn, and epigenetic age acceleration were greater in never smokers in comparison to current/former smokers.

CONCLUSION

Nonessential metals were positively associated with greater epigenetic age acceleration, with strongest associations observed between Cd and DunedinPACE and GrimAge acceleration. In contrast, essential metals were associated with lower epigenetic aging. Examining the influence of metal mixtures on epigenetic age acceleration can provide insight into metals and aging-related diseases.

Meteorological data source comparison-a case study in geospatial modeling of potential environmental exposure to abandoned uranium mine sites in the Navajo Nation

Meteorological (MET) data is a crucial input for environmental exposure models. While modeling exposure potential using geospatial technology is a common practice, existing studies infrequently evaluate the impact of input MET data on the level of uncertainty on output results. The objective of this study is to determine the effect of various MET data sources on the potential exposure susceptibility predictions. Three sources of wind data are compared: The North American Regional Reanalysis (NARR) database, meteorological aerodrome reports (METARs) from regional airports, and data from local MET weather stations. These data sources are used as inputs into a machine learning (ML) driven GIS Multi-Criteria Decision Analysis (GIS-MCDA) geospatial model to predict potential exposure to abandoned uranium mine sites in the Navajo Nation. Results indicate significant variations in results derived from different wind data sources. After validating the results from each source using the National Uranium Resource Evaluation (NURE) database in a geographically weighted regression (GWR), METARs data combined with the local MET weather station data showed the highest accuracy, with an average R2 of 0.74. We conclude that local direct measurement-based data (METARs and MET data) produce a more accurate prediction than the other sources evaluated in the study. This study has the potential to inform future data collection methods, leading to more accurate predictions and better-informed policy decisions surrounding environmental exposure susceptibility and risk assessment.

Environmentally Mediated Health Disparities

We describe important settings where environmental exposure leads to disease disparities. Lead exposure in urban settings disproportionately impacts the urban Black poor. Native Americans have been forcibly relocated to areas of the West that have arsenic-contaminated groundwater or exposure to radionuclides near mines and nuclear development. Latino farm workers are disproportionately exposed to pesticides and herbicides. These chemicals are associated with cancer, neuropsychiatric disorders, renal failure, and respiratory disorders. The rural poor, both white and of color, are disproportionately impacted by hydraulic fracturing, exposing residents to volatile organic compounds such as toluene and benzene and heavy metals such as lead and arsenic. The urban and rural poor are both exposed to air pollution that significantly impact health. Short- and long-term ambient air pollution exposure has been associated with all-cause cardiovascular disease, stroke, blood pressure, and ischemic heart disease. Cancer due to air pollution has disproportionately impacted poor communities like "Cancer Alley" where numerous industrial sources are geographically clustered. Understanding local environmental hazards and available resources to address them can enhance the quality of medical care.

Probabilistic risk assessment of residential exposure to metal(loid)s in a mining impacted community

The "Gold Country" region of California is impacted by legacy and active gold mines. Concomitantly, Gold Country has an increased rate of female breast cancer relative to the state average. Using community-based participatory research methods, 40 participants completed surveys and collected a total of 354 water, soil, home-grown foods, and dust samples from their homes, which we compared to state, federal, and international contamination standards for arsenic, cadmium, and lead. All soil samples exceeded U.S. EPA and California EPA soil standards for arsenic. When comparing other media to state, federal and international standards for arsenic, cadmium, and lead, 15 additional exceedances for indoor/outdoor dust, drinking water, and/or vegetable were documented. A probabilistic risk assessment was conducted to determine an adult female's exposure to arsenic, cadmium, and lead and estimated risk. Arsenic exposure, due largely to water (63.5 %) and homegrown food (33.3 %), presents carcinogenic risks in excess of the EPA recommended upper limit for contaminated sites (1 × 10-4) in 12.5 % of scenarios, and exceeds a risk level of 1 × 10-6 in 98.0 % of cases. Cadmium exposure results mainly from homegrown food consumption (83.7 %), and lead exposure results from a broader range of sources. This research indicates that rural areas in Gold Country face environmental exposures different than in urban areas. Exposure to arsenic in the female population of Gold Country may be driven by consumption of home-grown foods and water, and exposure to cadmium is driven by home-grown food intake. Since mining sites are of concern internationally, this risk assessment process and associated findings are significant and can be used to inform and tailor public health interventions. The weight of the evidence suggests that the arsenic exposure identified in this study could contribute to increases in the cancer rate among those living in Gold Country, California.

An equity and environmental justice assessment of anti-science actions during the Trump administration

In the United States, science shapes federal health and safety protections, but political officials can and do politicize federal science and science-based safeguards. Many presidential administrations have politicized science, but under the administration of President Trump, these attacks on science-such as buried research, censored scientists, halted data collection-increased in number to unprecedented levels. Underserved communities bore the brunt of the harms. Such attacks disproportionately harm Black, Indigenous, low-income communities, and communities of color, all of whom have long been burdened by pollution exposure and other stressors. We analyze the effects on underserved communities of the Trump administration's anti-science environmental and public health policy actions and offer policy recommendations for current and future administrations. Our goal is to strengthen scientific integrity, prioritize health disparity research, and meaningfully engage affected communities in federal rulemaking.

Blood cadmium, lead, manganese, mercury, and selenium levels in American Indian populations: The Strong Heart Study

BACKGROUND

Many American Indian (AI) communities are in areas affected by environmental contamination, such as toxic metals. However, studies assessing exposures in AI communities are limited. We measured blood metals in AI communities to assess historical exposure and identify participant characteristics associated with these levels in the Strong Heart Study (SHS) cohort.

METHOD

Archived blood specimens collected from participants (n = 2014, all participants were 50 years of age and older) in Arizona, Oklahoma, and North and South Dakota during SHS Phase-III (1998-1999) were analyzed for cadmium, lead, manganese, mercury, and selenium using inductively coupled plasma triple quadrupole mass spectrometry. We conducted descriptive analyses for the entire cohort and stratified by selected subgroups, including selected demographics, health behaviors, income, waist circumference, and body mass index. Bivariate associations were conducted to examine associations between blood metal levels and selected socio-demographic and behavioral covariates. Finally, multivariate regression models were used to assess the best model fit that predicted blood metal levels.

FINDINGS

All elements were detected in 100% of study participants, with the exception of mercury (detected in 73% of participants). The SHS population had higher levels of blood cadmium and manganese than the general U.S. population 50 years and older. The median blood mercury in the SHS cohort was at about 30% of the U.S. reference population, potentially due to low fish consumption. Participants in North Dakota and South Dakota had the highest blood cadmium, lead, manganese, and selenium, and the lowest total mercury levels, even after adjusting for covariates. In addition, each of the blood metals was associated with selected demographic, behavioral, income, and/or weight-related factors in multivariate models. These findings will help guide the tribes to develop education, outreach, and strategies to reduce harmful exposures and increase beneficial nutrient intake in these AI communities.

Chronic Community Exposure to Environmental Metal Mixtures Is Associated with Selected Cytokines in the Navajo Birth Cohort Study (NBCS)

Many tribal populations are characterized by health disparities, including higher rates of infection, metabolic syndrome, and cancer-all of which are mediated by the immune system. Members of the Navajo Nation have suffered chronic low-level exposure to metal mixtures from uranium mine wastes for decades. We suspect that such metal and metalloid exposures lead to adverse health effects via their modulation of immune system function. We examined the relationships between nine key metal and metalloid exposures (in blood and urine) with 11 circulating biomarkers (cytokines and CRP in serum) in 231 pregnant Navajo women participating in the Navajo Birth Cohort Study. Biomonitored levels of uranium and arsenic species were considerably higher in participants than NHANES averages. Each biomarker was associated with a unique set of exposures, and arsenic species were generally immunosuppressive (decreased cellular and humoral stimulating cytokines). Overall, our results suggest that environmental metal and metalloid exposures modulate immune status in pregnant Navajo women, which may impact long-term health outcomes in mothers and their children.

Implementation of Indigenous Food Tax Policies in Stores on Navajo Nation

In 2014, the Navajo Nation Healthy Diné Nation Act (HDNA) was enacted and permanently approved in 2020; HDNA places a 2% surtax on unhealthy foods and beverages, while other 2014 legislation exempted healthy food items from the 6% regular sales tax. Little is known about Navajo Nation store manager/owner perspectives toward the HDNA and how best to support stores to implement the legislation. Purposive sampling was used to ensure a balanced sample of correct HDNA implementers, incorrect HDNA implementers, and stores which made healthy store changes over the past 6 years. Three community-based interviewers collected surveys by phone or in-person. Frequency of closed-ended questions was quantified, and open-ended responses were coded using thematic analysis. Of 29 identified sample stores, 20 were interviewed to reach saturation. Eleven of 20 stores made changes improving their healthy food environments. Barriers included lack of equipment (6/20) and low consumer demand (5/20). Facilitators included consumer awareness and increased produce supply options (5/20). Sixteen of 20 stores supported HDNA continuation. Facilitators to HDNA implementation included orientation and informational materials (6/20) and promotion of tax-free items (5/20). Barriers included confusion about the tax (6/20) and tax exemption (5/20). Suggestions for support included printed materials (6/20) and store training (5/20). HDNA benefits included greater awareness of healthy choices among staff (7/20) and customer-community members (2/20). Most managers and owners expressed receiving support for healthy store changes and HDNA, but also identified a need for added resources and support. Findings inform legislative action to promote timely and appropriate uptake of HDNA, and support equitable, healthy food systems.

Supporting the Health and Well-Being of Indigenous Communities: A Position Paper From the American College of Physicians

Indigenous peoples in the United States experience many health disparities and barriers to accessing health care services. In addition, Indigenous communities experience poor social drivers of health, including disproportionately high rates of food insecurity, violence, and poverty, among others. These challenges are unsurprising, given historical societal discrimination toward Indigenous peoples and government policies of violence, forced relocation with loss of ancestral home, and erasure of cultures and traditions. Indigenous peoples have displayed resilience that has sustained their communities through these hardships. Through treaties between the federal government and Indigenous nations, the federal government has assumed a trust responsibility to provide for the health and well-being of Indigenous populations through the direct provision of health care services and financial support of tribally operated health systems. However, despite serving a population that has endured substantial historical trauma and subsequent health issues, federal programs serving Indigenous peoples receive inadequate federal funding and substantially fewer resources compared with other federal health care programs. Access to care is further challenged by geographic isolation and health care workforce vacancies. Given the history of Indigenous peoples in the United States and their treatment by the federal government and society, the American College of Physicians (ACP) asserts the federal government must faithfully execute its trust responsibility through increased funding and resources directed toward Indigenous communities and the undertaking of concerted policy efforts to support the health and well-being of Indigenous people. ACP believes that these efforts must be community-driven, Indigenous-led, and culturally appropriate and accepted, and center values of respect and self-determination.

Radioactive releases from the nuclear power sector and implications for child health

Although radioactivity is released routinely at every stage of nuclear power generation, the regulation of these releases has never taken into account those potentially most sensitive-women, especially when pregnant, and children. From uranium mining and milling, to fuel manufacture, electricity generation and radioactive waste management, children in frontline and Indigenous communities can be disproportionately harmed due to often increased sensitivity of developing systems to toxic exposures, the lack of resources and racial and class discrimination. The reasons for the greater susceptibility of women and children to harm from radiation exposure is not fully understood. Regulatory practices, particularly in the establishment of protective exposure standards, have failed to take this difference into account. Anecdotal evidence within communities around nuclear facilities suggests an association between radiation exposure and increases in birth defects, miscarriages and childhood cancers. A significant number of academic studies tend to ascribe causality to other factors related to diet and lifestyle and dismiss these health indicators as statistically insignificant. In the case of a major release of radiation due to a serious nuclear accident, children are again on the frontlines, with a noted susceptibility to thyroid cancer, which has been found in significant numbers among children exposed both by the 1986 Chornobyl nuclear accident in Ukraine and the 2011 Fukushima-Daiichi nuclear disaster in Japan. The response among authorities in Japan is to blame increased testing or to reduce testing. More independent studies are needed focused on children, especially those in vulnerable frontline and Indigenous communities. In conducting such studies, greater consideration must be applied to culturally significant traditions and habits in these communities.

U(VI) binding onto electrospun polymers functionalized with phosphonate surfactants

We previously observed that phosphonate functionalized electrospun nanofibers can uptake U(VI), making them promising materials for sensing and water treatment applications. Here, we investigate the optimal fabrication of these materials and their mechanism of U(VI) binding under the influence of environmentally relevant ions (e.g., Ca²⁺ and CO 3 2 - ). We found that U(VI) uptake was greatest on polyacrylonitrile (PAN) functionalized with longer-chain phosphonate surfactants (e.g., hexa- and octadecyl phosphonate; HDPA and ODPA, respectively), which were better retained in the nanofiber after surface segregation. Subsequent uptake experiments to better understand specific solid-liquid interfacial interactions were carried out using 5 mg of HDPA-functionalized PAN mats with 10 μM U at pH 6.8 in four systems with different combinations of solutions containing 5 mM calcium (Ca²⁺) and 5 mM bicarbonate ( HCO 3 - ). U uptake was similar in control solutions containing no Ca²⁺ and HCO 3 - (resulting in 19 ± 3% U uptake), and in those containing only 5 mM Ca²⁺ (resulting in 20 ± 3% U uptake). A decrease in U uptake (10 ± 4% U uptake) was observed in experiments with HCO 3 - , indicating that UO₂-CO₃ complexes may increase uranium solubility. Results from shell-by-shell EXAFS fitting, aqueous extractions, and surface-enhanced Raman scattering (SERS) indicate that U is bound to phosphonate as a monodentate inner sphere surface complex to one of the hydroxyls in the phosphonate functional groups. New knowledge derived from this study on material fabrication and solid-liquid interfacial interactions will help to advance technologies for use in the in-situ detection and treatment of U in water.

The immunotoxicity of natural and depleted uranium: From cells to people

Uranium is a naturally occurring element found in the environment as a mixture of isotopes with differing radioactive properties. Enrichment of mined material results in depleted uranium waste with substantially reduced radioactivity but retains the capacity for chemical toxicity. Uranium mine and milling waste are dispersed by wind and rain leading to environmental exposures through soil, air, and water contamination. Uranium exposure is associated with numerous adverse health outcomes in humans, yet there is limited understanding of the effects of depleted uranium on the immune system. The purpose of this review is to summarize findings on uranium immunotoxicity obtained from cell, rodent and human population studies. We also highlight how each model contributes to an understanding of mechanisms that lead to immunotoxicity and limitations inherent within each system. Information from population, animal, and laboratory studies will be needed to significantly expand our knowledge of the contributions of depleted uranium to immune dysregulation, which may then inform prevention or intervention measures for exposed communities.

Metal(loid)s in Common Medicinal Plants in a Uranium Mining-Impacted Area in Northwestern New Mexico, USA

The objective of this study was to determine uranium (U) and other metal(loid) concentrations (As, Cd, Cs, Pb, Mo, Se, Th, and V) in eight species of plants that are commonly used for medicinal purposes on Diné (Navajo) lands in northwestern New Mexico. The study setting was a prime target for U mining, where more than 500 unreclaimed abandoned U mines and structures remain. The plants were located within 3.2 km of abandoned U mines and structures. Plant biota samples (N = 32) and corresponding soil sources were collected. The samples were analyzed using Inductively Coupled Plasma−Mass Spectrometry. In general, the study findings showed that metal(loid)s were concentrated greatest in soil > root > aboveground plant parts, respectively. Several medicinal plant samples were found to exceed the World Health Organization Raw Medicinal Plant Permissible Level for As and Cd; however, using the calculated human intake data, Reference Dietary Intakes, Recommended Dietary Allowances, and tolerable Upper Limits, the levels were not exceeded for those with established food intake or ingestion guidelines. There does not appear to be a dietary food rise of metal(loid) ingestion based solely on the eight medicinal plants examined. Food intake recommendations informed by research are needed for those who may be more sensitive to metal(loid) exposure. Further research is needed to identify research gaps and continued surveillance and monitoring are recommended for mining-impacted communities.

Racial and Gender Diversity Among Students and Faculty in EHAC-Accredited Environmental Health Sciences Programs: Trend Analysis from 2009 to 2021

Diversity in the environmental health sciences (EHS) workforce is crucial in providing culturally sensitive services to diverse communities. This may be influenced by academic faculty training a diverse student body in the field of environmental health. This study aimed to characterize the diversity of students and faculty in EHS programs accredited by the National Environmental Health Science and Protection Accreditation Council (EHAC). A retrospective analysis was conducted on secondary data obtained from annual surveys administered to program directors in EHAC-accredited academic programs that included both undergraduate and graduate EHS degrees. The database covered surveys on gender and race that were conducted by EHAC for 12 academic years spanning 2009-2010 to 2020-2021. Results show most students (undergraduate and graduate) were female (54.4% and 52.1%, respectively) and white (61.0% and 50.7%, respectively). Increasing trends were observed over the last 12 years (2009-2021) in female undergraduate (from 53.7% to 59.8%) and graduate (from 47.1% to 60.3%) students and in non-white undergraduate students (from 40.0% to 48.2%). Most faculty (teaching in undergraduate and graduate programs) were male (64.4% and 64.3%, respectively) and white (77.9% and 92.1%, respectively). Increasing trends were observed from 2009 to 2021 in female faculty teaching undergraduate (from 27.7% to 42.2%) and graduate (from 31.3% to 42.1%) students. Native American, Alaska Native, Native Hawaiian, and Pacific Islander are consistently the most underrepresented racial groups in both undergraduate and graduate students and faculty. This study provides baseline data on the diversity of students and faculty in EHAC-accredited programs, which is important in informing future research and efforts to increase such diversity. Gender and racial disparity in EHS students and faculty needs to be addressed to provide necessary support to women and non-White constituents by institutional change in culture through active recruitment and by stronger collaboration between professional organizations and minority groups.

Envisioning healthy futures: Youth perceptions of justice-oriented environments and communities in Northern British Columbia Canada

Through an anti-colonial and critical race theoretical framework as well as arts-based methods (photovoice) that engage Indigenous and non-Indigenous youth, we explore the question: what do youth perceive as healthy and just environments and communities? Youth identified two overarching, strength-based messages: Firstly, youth demonstrate the need for a structural-level analysis of the conditions that influence individual-level outcomes of environmental health. Secondly, youth perspectives on healthy and justice-oriented environments and communities challenge environmental health scholars to consider youth as powerful actors. Youth perspectives of healthy and justice-oriented communities present a necessarily structural perspective to consider not only the impacts of environmental decision-making on health, but the conditions that have allowed for harmful impacts. In doing so, youth demonstrate the need for intersectional and complex understandings of health and wellbeing when discussing the environment. And, as we argue here, challenge us as scholars of environmental health to do the same.

Environmental and occupational health on the Navajo Nation: a scoping review

A scoping review was performed to answer: what environmental health concerns have been associated with adverse health outcomes in the Navajo Nation? The review focused on occupational and ambient environmental exposures associated with human industrial activities. The search strategy was implemented in PubMed, and two investigators screened the retrieved literature. Thirteen studies were included for review. Data were extracted using the matrix method. Six studies described associations between work in uranium mining and cancer. Six studies focused on environmental exposures to uranium mine waste and other metals, with outcomes that included biological markers, kidney disease, diabetes and hypertension, and adverse birth outcomes. One study explored occupational exposure to Sin Nombre Virus and infection. Most research has focused on the health effects of uranium, where occupational exposures occurred among miners and environmental exposures are a legacy of uranium mining and milling. Gaps exist with respect to health outcomes associated with current occupations and the psychosocial impact of environmental hazards. Other environmental exposures and hazards are known to exist on the Navajo Nation, which may warrant epidemiologic research.

Air Pollution in American Indian Versus Non-American Indian Communities, 2000-2018

Objectives. To compare fine particulate matter (PM2.5) concentrations in American Indian (AI)-populated with those in non-AI-populated counties over time (2000-2018) in the contiguous United States. Methods. We used a multicriteria approach to classify counties as AI- or non--AI-populated. We ran linear mixed effects models to estimate the difference in countywide annual PM2.5 concentrations from well-validated prediction models and monitoring sites (modeled and measured PM2.5, respectively) in AI- versus non-AI-populated counties. Results. On average, adjusted modeled PM2.5 concentrations in AI-populated counties were 0.38 micrograms per cubic meter (95% confidence interval [CI] = 0.23, 0.54) lower than in non-AI-populated counties. However, this difference was not constant over time: in 2000, modeled concentrations in AI-populated counties were 1.46 micrograms per cubic meter (95% CI = 1.25, 1.68) lower, and by 2018, they were 0.66 micrograms per cubic meter (95% CI = 0.45, 0.87) higher. Over the study period, adjusted modeled PM2.5 mean concentrations decreased by 2.13 micrograms per cubic meter in AI-populated counties versus 4.26 micrograms per cubic meter in non-AI-populated counties. Results were similar for measured PM2.5. Conclusions. This study highlights disparities in PM2.5 trends between AI- and non-AI-populated counties over time, underscoring the need to strengthen air pollution regulations and prevention implementation in tribal territories and areas where AI populations live. (Am J Public Health. 2022;112(4): 615-623. https://doi.org/10.2105/AJPH.2021.306650).

Sociodemographic inequalities in uranium and other metals in community water systems across the USA, 2006-11: a cross-sectional study

BACKGROUND

The US Environmental Protection Agency (EPA) currently sets maximum contaminant levels (MCLs) for ten metals or metalloids in public drinking water systems. Our objective was to estimate metal concentrations in community water systems (CWSs) across the USA, to establish if sociodemographic or regional inequalities in the metal concentrations exist, and to identify patterns of concentrations for these metals as a mixture.

METHODS

We evaluated routine compliance monitoring records for antimony, arsenic, barium, beryllium, cadmium, chromium, mercury, selenium, thallium, and uranium, collected from 2006-11 (2000-11 for uranium; timeframe based on compliance monitoring requirements) by the US EPA in support of their second and third Six-Year Reviews for CWSs. Arsenic, barium, chromium, selenium, and uranium (detectable in >10% records) were included in the main analyses (subgroup and metal mixture analyses; arsenic data reported previously). We compared the mean, 75th percentile, and 95th percentile contaminant concentrations and the percentage of CWSs with concentrations exceeding the MCL across subgroups (region, sociodemographic county-cluster, size of population served, source water type, and CWSs exclusively serving correctional facilities). We evaluated patterns in CWS metal concentration estimate profiles via hierarchical cluster analysis. We created an online interactive map and dashboard of estimated CWS metal concentrations for use in future analyses.

FINDINGS

Average metal concentrations were available for a total of 37 915 CWSs across the USA. The total number of monitoring records available was approximately 297 000 for arsenic, 165 000 for barium, 167 000 for chromium, 165 000 for selenium, and 128 000 for uranium. The percentage of analysed CWSs with average concentrations exceeding the MCL was 2·6% for arsenic (MCL=10 μg/L; nationwide mean 1·77 μg/L; n=36 798 CWSs), 2·1% for uranium (MCL=30 μg/L; nationwide mean 4·37 μg/L; n=14 503 CWSs), and less than 0·1% for the other metals. The number of records with detections was highest for uranium (63·1%). 75th and 95th percentile concentrations for uranium, chromium, barium, and selenium were highest for CWSs serving Semi-Urban, Hispanic communities, CWSs reliant on groundwater, and CWSs in the Central Midwest. Hierarchical cluster analysis revealed two distinct clusters: an arsenic-uranium-selenium cluster and a barium-chromium cluster.

INTERPRETATIONS

Uranium is an under-recognised contaminant in CWSs. Metal concentrations (including uranium) are elevated in CWSs serving Semi-Urban, Hispanic communities independent of location or region, highlighting environmental justice concerns.

FUNDING

US National Institutes of Health Office of the Director, US National Institutes for Environmental Health Sciences, and US National Institute of Dental and Craniofacial Research.

Building Environmental Health and Genomics Literacy among Healthcare Providers Serving Vulnerable Communities: An Innovative Educational Framework

This study addresses healthcare providers’ knowledge deficits in environmental health and genetics, and primarily focuses on student nurses and nurses serving marginalized, low-income communities frequently exposed to environmental toxicants. Our approach to improve public health is unique, combining hands-on modeling exercises with case-based lessons in addition to three targeted 40 min lectures on toxicology. These lectures included the team’s community-based environmental health research among Indigenous peoples of the U.S. The hands-on approach employed DNA and protein molecular models designed to demonstrate normal and dysfunctional molecules, as well as genetic variants in world populations. The models provided learners with visuals and an experience of “learning by doing.” Increased awareness of the effects of environmental toxicants is the first step toward improving health care for exposed communities. We measured knowledge gains by pre- and post-tests among student nurses and nurses serving Native Americans living both in urban and rural areas of the U.S. (n = 116). The modeling lessons illustrated genetic variants in liver proteins common in Native peoples and their resulting health vulnerabilities. Participants were engaged and enthusiastic; and pre- and post-test results reported substantial knowledge gains and a greater understanding of genetic susceptibility (p < 0.0001). Our study demonstrates the utility of this framework across diverse populations and remote communities.

Prenatal Metal Exposures and Infants' Developmental Outcomes in a Navajo Population

Early-life exposure to environmental toxicants can have detrimental effects on children's neurodevelopment. In the current study, we employed a causal modeling framework to examine the direct effect of specific maternal prenatal exposures on infants' neurodevelopment in the context of co-occurring metals. Maternal metal exposure and select micronutrients' concentrations were assessed using samples collected at the time of delivery from mothers living across Navajo Nation with community exposure to metal mixtures originating from abandoned uranium mines. Infants' development across five domains was measured at ages 10 to 13 months using the Ages and Stages Questionnaire Inventory (ASQ:I), an early developmental screener. After adjusting for effects of other confounding metals and demographic variables, prenatal exposure to lead, arsenic, antimony, barium, copper, and molybdenum predicted deficits in at least one of the ASQ:I domain scores. Strontium, tungsten, and thallium were positively associated with several aspects of infants' development. Mothers with lower socioeconomic status (SES) had higher lead, cesium, and thallium exposures compared to mothers from high SES backgrounds. These mothers also had infants with lower scores across various developmental domains. The current study has many strengths including its focus on neurodevelopmental outcomes during infancy, an understudied developmental period, and the use of a novel analytical method to control for the effects of co-occurring metals while examining the effect of each metal on neurodevelopmental outcomes. Yet, future examination of how the effects of prenatal exposure on neurodevelopmental outcomes unfold over time while considering all potential interactions among metals and micronutrients is warranted.

Building structures of environmental repossession to reclaim land, self-determination and Indigenous wellness

In Canada, Indigenous health inequalities are sustained by colonial structures that create social disadvantage and limit Indigenous self-determination to Land. Drawing on the concept of environmental repossession, this study explores how Indigenous communities are building local structures to reclaim their territories and renew the values, responsibilities and knowledges tied to these places for wellness. Specifically, this study examines the meanings of the everyday work of the Department of Sustainable Development in Biigtigong Nishnaabeg and shares lessons for other communities seeking to foster self-determination over Land, identity and wellness. Qualitative analysis of interviews with current and former department staff members support an advanced understanding of how repossession strategies are sustained by Indigenous communities to foster place-based goals and address structural barriers to wellness.

Air, Land, and Sea: Gene-Environment Interaction in Chronic Disease

Each of us reflects a unique convergence of DNA and the environment. Over the past 2 decades, huge biobanks linked to electronic medical records have positioned the clinical and scientific communities to understand the complex genetic architecture underlying many common diseases. Although these efforts are producing increasingly accurate gene-based risk prediction algorithms for use in routine clinical care, the algorithms often fail to include environmental factors. This review explores the concept of heritability (genetic vs nongenetic determinants of disease), with emphasis on the role of environmental factors as risk determinants for common complex diseases influenced by air and water quality. Efforts to define patient exposure to specific toxicants in practice-based data sets will deepen our understanding of diseases with low heritability, and improved land management practices will reduce the burden of disease.

A Secure and Reusable Software Architecture for Supporting Online Data Harmonization

Retrospective data harmonization across multiple research cohorts and studies is frequently done to increase statistical power, provide comparison analysis, and create a richer data source for data mining. However, when combining disparate data sources, harmonization projects face data management and analysis challenges. These include differences in the data dictionaries and variable definitions, privacy concerns surrounding health data representing sensitive populations, and lack of properly defined data models. With the availability of mature open-source web-based database technologies, developing a complete software architecture to overcome the challenges associated with the harmonization process can alleviate many roadblocks. By leveraging state-of-the-art software engineering and database principles, we can ensure data quality and enable cross-center online access and collaboration. This paper outlines a complete software architecture developed and customized using the Django web framework, leveraged to harmonize sensitive data collected from three NIH-support birth cohorts. We describe our framework and show how we successfully overcame challenges faced when harmonizing data from these cohorts. We discuss our efforts in data cleaning, data sharing, data transformation, data visualization, and analytics, while reflecting on what we have learned to date from these harmonized datasets.

Co-exposure of sodium arsenite and uranyl acetate differentially alters gene expression in CD3/CD28 activated CD4+ T-cells

Communities in the western region of the United States experience environmental exposure to metal mixtures from living in proximity to numerous unremediated abandoned uranium mines. Metals including arsenic and uranium co-occur in and around these sites at levels higher than the United States Environmental Protection Agency maximum contaminant levels. To address the potential effect of these metals on the activation of CD4+ T-cells, we used RNA sequencing methods to determine the effect of exposure to sodium arsenite (1 μM and 10 μM), uranyl acetate (3 μM and 30 μM) or a mixture of sodium arsenite and uranyl acetate (1 μM sodium arsenite + 3 μM uranyl acetate). Sodium arsenite induced a dose dependent effect on activation associated gene expression; targeting immune response genes at the lower dose. Increases in oxidative stress gene expression were observed with both sodium arsenite doses. While uranyl acetate alone did not significantly alter activation associated gene expression, the mixture of uranyl acetate with sodium arsenite demonstrated a combined effect relative to sodium arsenite alone. The results demonstrate the need to investigate metal and metalloid mixtures at environmentally relevant concentrations to better understand the toxicological impact of these mixtures on T-cell activation, function and immune dysregulation.

Pervasive structural racism in environmental epidemiology

BACKGROUND

Epistemological biases in environmental epidemiology prevent the full understanding of how racism's societal impacts directly influence health outcomes. With the ability to focus on "place" and the totality of environmental exposures, environmental epidemiologists have an important opportunity to advance the field by proactively investigating the structural racist forces that drive disparities in health.

OBJECTIVE

This commentary illustrates how environmental epidemiology has ignored racism for too long. Some examples from environmental health and male infertility are used to illustrate how failing to address racism neglects the health of entire populations.

DISCUSSION

While research on environmental justice has attended to the structural sources of environmental racism, this work has not been fully integrated into the mainstream of environmental epidemiology. Epidemiology's dominant paradigm that reduces race to a mere data point avoids the social dimensions of health and thus fails to improve population health for all. Failing to include populations who are Black, Indigenous, and people of color (BIPOC) in health research means researchers actually know very little about the effect of environmental contaminants on a range of population health outcomes. This commentary offers different practical solutions, such as naming racism in research, including BIPOC in leadership positions, mandating requirements for discussing "race", conducting far more holistic analyses, increasing community participation in research, and improving racism training, to address the myriad of ways in which structural racism permeates environmental epidemiology questions, methods, results and impacts.

Risks to global biodiversity and Indigenous lands from China's overseas development finance

China has become one of the world's largest lenders in overseas development finance. Development projects, such as roads, railways and power plants, often drive biodiversity loss and infringe on Indigenous lands, yet the risks implicit in China's overseas development finance are poorly understood. Here we examine the extent to which projects financed by China's policy banks between 2008 and 2019 occur within and adjacent to areas where large-scale investment can present considerable risks to biodiversity and Indigenous peoples. Further, we compare these risks with those posed by similar projects financed by the World Bank, previously the world's largest source of development finance. We found that 63% of China-financed projects overlap with critical habitats, protected areas or Indigenous lands, with up to 24% of the world's threatened birds, mammals, reptiles and amphibians potentially impacted by the projects. Hotspots of the risks are primarily distributed in northern sub-Saharan Africa, Southeast Asia and parts of South America. Overall, China's development projects pose greater risks than those of the World Bank, particularly within the energy sector. These results provide an important global outlook of socio-ecological risks that can guide strategies for greening China's development finance around the world.

Spatial relationship between well water arsenic and uranium in Northern Plains native lands

Arsenic and uranium in unregulated private wells affect many rural populations across the US. The distribution of these contaminants in the private wells of most American Indian communities is poorly characterized, and seldom studied together. Here, we evaluate the association between drinking water arsenic and uranium levels in wells (n = 441) from three tribal regions in North Dakota and South Dakota participating in the Strong Heart Water Study. Groundwater contamination was extensive; 29% and 7% of wells exceeded maximum contaminant levels for arsenic and uranium respectively. 81% of wells had both arsenic and uranium concentrations at one-tenth of their human-health benchmark (arsenic, 1 μg/L; uranium 3 μg/L). Well arsenic and uranium concentrations were uncorrelated (rs = 0.06); however, there appeared to be a spatial correlation of wells co-contaminated by arsenic and uranium associated with flow along a geologic contact. These findings indicate the importance of measuring multiple metals in well water, and to understand underlying hydrogeological conditions. The underlying mechanisms for the prevalence of arsenic and uranium across Northern Plains Tribal Lands in the US, and in particular the occurrence of both elevated arsenic and uranium in drinking water wells in this region, demands further study.

Growing Disparity in the Incidence of Colorectal Cancer among Non-Hispanic American Indian and Alaska Native Populations-United States, 2013-2017

BACKGROUND

American Indian and Alaska Native (AI/AN) populations have experienced regional variation and disparities in colorectal cancer incidence rates.

METHODS

We examined colorectal cancer incidence (2013-2017) and colorectal cancer incidence trends (1999-2017) among AI/AN persons. Incidence data were linked to Indian Health Service enrollment records, and analyses were restricted to Purchased/Referred Care Delivery Areas. Incidence rates of colorectal cancer among AI/AN and White persons were analyzed in six geographic regions; Hispanic persons were excluded. Incidence trends were analyzed using linear modeling.

RESULTS

During 2013-2017, colorectal cancer incidence was 41% higher among AI/AN than among White persons. AI/AN incidence rates per 100,000 varied regionally from 34.4 in the East to 96.1 in Alaska. Compared with White persons, AI/AN persons had higher colorectal cancer incidence rates among all age strata and were more likely to have late-stage diagnoses. Incidence rate trends indicated significant increases among both AI/AN and White persons ages <50 years and among AI/AN persons ages 50-64 years. The colorectal cancer incidence rate trend increased among AI/AN persons in the Southwest.

CONCLUSIONS

The disparity of colorectal cancer incidence rates between AI/AN and White persons has widened since 2005-2009. AI/AN populations have higher colorectal cancer incidence compared with White populations, especially in the Alaska region.

IMPACT

Our finding of increased colorectal cancer incidence disparities suggests that enhanced screening efforts and culturally appropriate clinical and public health interventions are needed among AI/AN persons overall, and especially in regions and age groups in which colorectal cancer rates are increasing.

Uptake and Toxicity of Respirable Carbon-Rich Uranium-Bearing Particles: Insights into the Role of Particulates in Uranium Toxicity

Particulate matter (PM) presents an environmental health risk for communities residing close to uranium (U) mine sites. However, the role of the particulate form of U on its cellular toxicity is still poorly understood. Here, we investigated the cellular uptake and toxicity of C-rich U-bearing particles as a model organic particulate containing uranyl citrate over a range of environmentally relevant concentrations of U (0-445 μM). The cytotoxicity of C-rich U-bearing particles in human epithelial cells (A549) was U-dose-dependent. No cytotoxic effects were detected with soluble U doses. Carbon-rich U-bearing particles with a wide size distribution (<10 μm) presented 2.7 times higher U uptake into cells than the particles with a narrow size distribution (<1 μm) at 100 μM U concentration. TEM-EDS analysis identified the intracellular translocation of clusters of C-rich U-bearing particles. The accumulation of C-rich U-bearing particles induced DNA damage and cytotoxicity as indicated by the increased phosphorylation of the histone H2AX and cell death, respectively. These findings reveal the toxicity of the particulate form of U under environmentally relevant heterogeneous size distributions. Our study opens new avenues for future investigations on the health impacts resulting from environmental exposures to the particulate form of U near mine sites.

"If the reindeer die, everything dies": The mental health of a Sámi community exposed to a mining project in Swedish Sápmi

In 2006, a British mining company started the process of extracting ore from Gállok/Kallak, in Swedish Sápmi. These grounds are used all year round for reindeer herding by the Sámi community Jåhkågasska tjiellde. While environmental impact assessments should be conducted by law in any development project in Sweden, the health component included is usually vague. The aim of this study was to understand the experiences and perceptions of the Sámi community regarding the current and potential health effects of the proposed mine.A qualitative study, including six in-depth interviews with members of the community, was conducted in 2020. Interviews were analysed using thematic analysis. Five themes were identified and organised in current and future impacts. Current impacts included “It’s like David’s battle against Goliath”, “It’s a slow process that takes a lot of power and energy”, “It’s a defense … like, to protect oneself”; with future impacts including: “If the reindeer die, everything dies”, “You would feel that you do not possess any power, [you would feel] overridden, pushed away, not liked”.The fear of losing current and future generations’ livelihoods appeared to be the main mediators of the current and potential worsened mental health experienced by the community.

Mine-site derived particulate matter exposure exacerbates neurological and pulmonary inflammatory outcomes in an autoimmune mouse model

The Southwestern United States has a legacy of industrial mining due to the presence of rich mineral ore deposits. The relationship between environmental inhaled particulate matter (PM) exposures and neurological outcomes within an autoimmune context is understudied. The aim of this study was to compare two regionally-relevant dusts from high-priority abandoned mine-sites, Claim 28 PM, from Blue Gap Tachee, AZ and St. Anthony mine PM, from the Pueblo of Laguna, NM and to expose autoimmune-prone mice (NZBWF1/J). Mice were randomly assigned to one of three groups (n = 8/group): DM (dispersion media, control), Claim 28 PM, or St. Anthony PM, subjected to oropharyngeal aspiration of (100 µg/50 µl), once per week for a total of 4 consecutive doses. A battery of immunological and neurological endpoints was assessed at 24 weeks of age including: bronchoalveolar lavage cell counts, lung gene expression, brain immunohistochemistry, behavioral tasks and serum autoimmune biomarkers. Bronchoalveolar lavage results demonstrated a significant increase in number of polymorphonuclear neutrophils following Claim 28 and St. Anthony mine PM aspiration. Lung mRNA expression showed significant upregulation in CCL-2 and IL-1ß following St. Anthony mine PM aspiration. In addition, neuroinflammation was present in both Claim 28 and St. Anthony mine-site derived PM exposure groups. Behavioral tasks resulted in significant deficits as determined by Y-maze new arm frequency following Claim 28 aspiration. Neutrophil elastase was significantly upregulated in the St. Anthony mine exposure group. Interestingly, there were no significant changes in serum autoantigens suggesting systemic inflammatory effects may be mediated through other molecular mechanisms following low-dose PM exposures.

Monitoring uranium mine pollution on Native American lands: Insights from tree bark particulate matter on the Spokane Reservation, Washington, USA

The uranium boom in the United States from the 1940's to the 1980's was a period of extensive uranium mining on Native American lands. However, detailed environmental investigations of the resulting uranium pollution are sparse and typically ignore contributions from airborne particulate matter. The Midnite Mine is a 350-acre inactive open pit uranium mine located on the Spokane Indian Reservation in eastern Washington that operated from 1954 to 1981. Approximately 2.4 million tons of ore and 33 million tons of waste rock were left behind in stockpiles and have also been utilized as gravel on access and haul roads. Although the Midnite Mine is now a Superfund Site, and governmental investigations of water and soil contamination have been done, no investigations of airborne particulate matter pollution have been conducted. This study applies tree bark from 31 Pinus ponderosa trees as a biomonitor of this airborne particulate matter. Bulk trace elemental analyses via inductively coupled plasma - mass spectrometry (ICP-MS) of tree bark show that U is the most abundant trace element of interest present up to 232 ppb. Other metals that are of potential human health concern include Th, Pb, and As which are present at 20 ppb, 104 ppb, and 20 ppb respectively. Calculated geoaccumulation indices determine these metals to be at high (U), moderate (Th), and low (Pb and As) levels of contamination. Detailed scanning electron microscopy (SEM) investigations of particulate matter from the surface of tree bark confirm that U and Th-bearing particulate matter exist in the <PM₁₀ size fraction while geospatial analyses indicate that uranium, thorium, and arsenic contamination are centralized along the Midnite Mine access road and at the nearby Dawn Mill where ore was further processed. Combined, these findings indicate that the nature and distribution of historic airborne particulate matter from the Midnite Mine and Dawn Mill provide context for potentially understanding past and current illness on the reservation. In addition, much needed context for future health and environmental studies for both local and national Native American populations is provided.

Uranium Exposure in American Indian Communities: Health, Policy, and the Way Forward

BACKGROUND

Uranium contamination of drinking-water sources on American Indian (AI) reservations in the United States is a largely ignored and underfunded public health crisis. With an estimated 40% of the headwaters in the western U.S. watershed, home to many AI reservation communities, being contaminated with untreated mine waste, the potential health effects have largely been unexplored. With AI populations already facing continued and progressive economic and social marginalization, higher prevalence of chronic disease, and systemic discrimination, associations between various toxicant exposures, including uranium, and various chronic conditions, need further examination.

OBJECTIVES

Uranium's health effects, in addition to considerations for uranium drinking-water testing, reporting, and mitigation in reference to AI communities through the lens of water quality, is reviewed.

DISCUSSION

A series of environmental health policy recommendations are described with the intent to proactively improve responsiveness to the water quality crisis in AI reservation communities in the United States specific to uranium. There is a serious and immediate need for better coordination of uranium-related drinking-water testing and reporting on reservations in the United States that will better support and guide best practices for uranium mitigation efforts. https://doi.org/10.1289/EHP7537.

Emerging investigator series: entrapment of uranium-phosphorus nanocrystals inside root cells of Tamarix plants from a mine waste site

We investigated the mechanisms of uranium (U) uptake by Tamarix (salt cedars) growing along the Rio Paguate, which flows throughout the Jackpile mine near Pueblo de Laguna, New Mexico. Tamarix were selected for this study due to the detection of U in the roots and shoots of field collected plants (0.6-58.9 mg kg-1), presenting an average bioconcentration factor greater than 1. Synchrotron-based micro X-ray fluorescence analyses of plant roots collected from the field indicate that the accumulation of U occurs in the cortex of the root. The mechanisms for U accumulation in the roots of Tamarix were further investigated in controlled-laboratory experiments where living roots of field plants were macerated for 24 h or 2 weeks in a solution containing 100 μM U. The U concentration in the solution decreased 36-59% after 24 h, and 49-65% in two weeks. Microscopic and spectroscopic analyses detected U precipitation in the root cell walls near the xylems of the roots, confirming the initial results from the field samples. High-resolution TEM was used to study the U fate inside the root cells, and needle-like U-P nanocrystals, with diameter <7 nm, were found entrapped inside vacuoles in cells. EXAFS shell-by-shell fitting suggest that U is associated with carbon functional groups. The preferable binding of U to the root cell walls may explain the U retention in the roots of Tamarix, followed by U-P crystal precipitation, and pinocytotic active transport and cellular entrapment. This process resulted in a limited translocation of U to the shoots in Tamarix plants. This study contributes to better understanding of the physicochemical mechanisms affecting the U uptake and accumulation by plants growing near contaminated sites.

Modulation of PARP activity by Monomethylarsonous (MMA+3) acid and uranium in mouse thymus

Arsenic exposure is well established to impair the function of zinc finger proteins, including PARP-1. Previous studies from our lab show that early developing T cells in the thymus are very sensitive to arsenite (As+3)-induced genotoxicity mediated through PARP-1 inhibition. Additionally, it has been shown that uranium (in the form of uranyl acetate, UA) also suppresses PARP-1 activity in HEK cells. However, very little is known about whether the As+3 metabolite, monomethylarsonous acid (MMA+3), also inhibits PARP-1 activity and if this is modified by combined exposures with other metals, such as uranium. In the present study, we found that MMA+3 significantly suppressed PARP-1 function, whereas UA at high concentrations significantly increased PARP-1 activity. To evaluate whether the effects on PARP-1 activity were mediated through oxidative stress, we measured the induction of hemoxygenase-1 (Hmox-1) expression by qPCR. MMA+3, but not UA, significantly induced oxidative stress; however, the inhibition of PARP-1 produced by MMA+3 was not reversed by the addition of the antioxidant, Tempol. Further evaluation revealed minimal interactive effects of MMA+3 and UA on PARP-1 function. Collectively, our results show that contrary to As+3, the suppressive effects of MMA+3 on PARP-1 were not substantially driven by oxidative stress. in mouse thymus cells. Results for this study provide important insights into the effects of MMA+3 and uranium exposures on PARP-1 function, which is essential for future studies focused on understanding the effects of complex environmentally relevant metal mixtures.