Factors influencing lead, mercury and other trace element exposure in birds from metal mining areas.

Non-ferrous metal mining is considered one of the largest sources of toxic metal released to the environment and may threaten ecosystems, notably biota. We explored how birds that inhabit non-ferrous metal mining sites are exposed to mercury, lead, and other trace elements by analyzing their feathers and verifying which factors may influence element concentrations in feathers. We sampled a total of 168 birds, representing 26 species, with different feeding habits and migration patterns in a non-polluted reference site and two historical metal mining areas: Almadén, which is considered one of the most heavily mercury-contaminated sites worldwide, and the Sierra Madrona mountains where lead has been mined since ancient times. The quantification of aluminum (Al), arsenic (As), barium (Ba), beryllium (Be), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), mercury (Hg), magnesium (Mg), manganese (Mn), molybdenum (Mo), nickel (Ni), lead (Pb), selenium (Se), thorium (Th), thallium (Tl), uranium (U), vanadium (V) and zinc (Zn) was performed by inductively coupled plasma mass spectrometry (ICP-MS). Feather analysis revealed contamination by Hg and Pb, in Almadén and Sierra Madrona, respectively. We found that granivorous birds had the lowest feather Hg levels compared to those found in omnivorous, insectivorous, and piscivorous species, whereas feather Pb was about twice as high in granivores and omnivores, than in insectivorous and piscivorous birds. We also found differences among study sites in 13 elements and confirmed the influence of feather age, migratory patterns of the birds, and external deposition of elements, on metal concentrations in the feathers. Our results highlight that despite the cessation of metal mining in the study areas, local avifauna are being exposed to Hg and Pb from abandoned mines and old tailings sites, indicating that appropriate measures are needed to protect biota from overexposure to these toxic metals.

Effect of mineral supplementation on lead bioavailability and toxicity biomarkers in sheep exposed to mining pollution.

The chronic exposure of livestock to lead (Pb) pollution in historical mining areas may represent significant and unnecessary costs for farmers and primary producers, in addition to important food safety risks. Here, we evaluate the effect of mineral supplements, in the form of a commercial mineral block (MB), to reduce Pb bioavailability and toxicity in sheep through an experimental approach under real farming conditions in an abandoned mining area. Blood, fecal Pb levels, and soil ingestion, along with different blood and plasma biomarkers were studied. Experiment 1 was carried out with 3-months-old female lambs, n = 54, fenced in two contiguous MB and non-MB-supplemented plots. After 20 days of treatment, blood Pb level was lower in MB-supplemented sheep than in those that were non-MB-supplemented. Experiment 2 was carried out with 2-months-old female lambs, n = 34, fenced in a single plot and MB-supplemented during the first 20 days of experiment. After MB supplementation, blood Pb level in sheep was also reduced by almost half, falling below the threshold of subclinical intoxication, and then increased again after 20 days without MB. Experiment 3 was carried out with adult rams, n = 10, fenced in a single MB-supplemented plot during the first 20 days of experiment. In this case, blood Pb level decreased by day 40. Soil ingestion was not reduced by MB supplementation in any of the experiments. MB supplementation favored antioxidant status by increasing SOD activity and reducing GPX activity and MDA levels. In conclusion, the MB supplementation seemed to reduce Pb bioavailability by increasing its fecal excretion, but renal excretion and bone deposition may also have favored the reduction of blood Pb concentration. Mineral supplements may be a new easy-to-apply and cost-effective way to reduce livestock exposure in Pb polluted sites.

Food safety risk assessment of metal pollution in crayfish from two historical mining areas: Accounting for bioavailability and cooking extractability.

Here we characterize the bioaccumulation of mercury (Hg) and lead (Pb) in red swamp crayfish (Procambarus clarkii) from two river courses in Central Spain that are impacted by historical Hg and Pb mining activities, respectively. We estimate the absolute oral bioavailability of metals in crayfish tissues by means of in vitro bioaccessibility simulations, and assess whether their consumption may imply a health risk for humans by estimating target hazard quotients and safe consumption rates. We also study the effect of cooking crayfish on the mobilization of the metal body burden in the context of the traditional Spanish cuisine. The results showed that crayfish from the mining districts accumulated a high level of Hg and Pb pollution in both the tail muscle and the carcass. The in vitro bioaccessibility of Hg and Pb in the edible part was 27.86 ±â€¯4.05 and 33.73 ±â€¯5.91%, respectively. Absolute bioavailability was estimated to be 38.31 for Hg, and 20.21 (adults) and 67.35% (children) for Pb. Risk indices indicated that, even after adjusting for bioavailability, it is not safe to consume crayfish from the mining-impacted rivers because of their high levels of Hg and Pb. Using the carcass as a condiment for flavouring should also be avoided. The cooking procedure extracted relatively small amounts of the total Hg (8.92 ±â€¯2.13%) and Pb (1.68 ±â€¯0.29%) body burden. Further research that will support human and ecological risk assessment, along with the implementation of advisory measures for the local population as regards crayfish consumption, are recommended.

Lead (Pb) in sheep exposed to mining pollution: implications for animal and human health.

Livestock from the ancient mining area of Sierra Madrona and Alcudia Valley (Spain) is exposed to elevated levels of lead (Pb), as previous studies based on blood monitoring have revealed. Here we have studied blood, liver and muscle Pb levels in sheep in order to know if Pb exposure could represent a risk for human consumers of the meat and offal of these animals. A cross-sectional study was conducted with ≥4 years old (adults) ewes from the mining area (n=46) and a control area (n=21). Blood samples were taken before the sacrifice at the slaughterhouse, and liver and muscle samples were taken thereafter. At the same time, 2-3 year old rams (subadults, n=17) were blood sampled in the mining area. Blood, liver and muscle Pb levels were higher in the mining than in the control area. Blood Pb concentration in the mining area (n= 44, mean: 6.7µg/dl in ewes and 10.9µg/dl in rams) was above background levels (>6µg/dl) in 73.3 percent of animals. Liver Pb concentration in 68 percent of sheep from the mining area (n=32, mean: 6.16µg/g dry weight, d.w.) exceeded the minimum level associated with toxic exposure (5µg/g d.w.) and 87.5 percent of liver samples were above European Union Maximum Residue Levels (MRL) established for offal destined for human consumption (0.5µg/g w.w.~1.4µg/g d.w.). On the contrary, none of the muscle samples in ewes exceeded the EU MRL (0.1µg/g w.w.~0.34µg/g d.w.) established for meat, which may be related to the decline of blood Pb levels with age observed in the present study. These results suggest a potential health effect for sheep exposed to Pb pollution in this area and implications for food safety, but further research with lamb meat may be necessary to refine the risk assessment for human consumers.

Youth Perspectives on the Flint Water Crisis and Its Health Effects.

Background: While the youth of Flint are at risk from the effects of the water crisis, little is known about their perspective of the impact of the water on their health. Objective: To explore adolescents' perceptions of living in Flint during the water crisis, its impact on their health, and ways to address the crisis and rebuild trust. Methods: In summer 2018, four focus groups were conducted with adolescents in Flint (ages 13 to 17 years). Group sessions were conducted by trained facilitators who were Flint residents along with members of the community-academic research team. Group sessions were audio-recorded and transcribed. Transcripts were reviewed and themes identified by the research team and youth from the focus groups. Results: Of the 53 participants, most identified as Black (66%) and male (64%). Participants expressed concern about the impact of the water on their health. They knew people who developed rashes, experienced cognitive changes, and who died, they believed, owing to the water. The crisis also led to psychological consequences for youth. They expressed ongoing mistrust of the water and of institutions that should protect them, as well as concern that exposure may have long-term effects on their health and their children's health. Despite these concerns, participants expressed resilience and a desire to share that they had the potential to live successful lives. Conclusion: Youth expressed concern about current and long-term health sequelae of the water crisis. Further work is needed to monitor the consequences of the crisis and to identify resident-informed approaches to mitigate its effects and rebuild trust.

Advancing Du Bois's Legacy Through Emancipatory Environmental Sociology.

Environmental sociology, while dedicating significant scholarship to issues of environmental racism and environmental justice, remains a predominately white subdiscipline that has not enjoyed general relevance across sociology. One of the drivers of the dominance of white perspectives in the subdiscipline is the lack of a core theoretical pillar that anchors the importance of racism to structuring inequitable environments. W.E.B. Du Bois not only offered a foundational approach to sociological inquiry, but also a deeply material perspective on the maintenance of racial inequities. Du Bois's approach to sociology lays the path for a liberatory approach that documents the scope of a problem, interrogates its drivers, and works with affected communities and allied resources to develop alternative models with transformative outcomes. This paper argues that an environmental understanding was original to Du Bois's methodology as demonstrated through his concept of the total environment. He connected inequitable environments to the legacy of racial capitalism, which he saw as driven by anti-Blackness. His solution was to advance Black solidarity and community cooperatives through Pan-Africanism. Du Bois' framework establishes an approach to conducting emancipatory environmental sociology that provides theoretical and methodological legitimacy for engaging in partnership with marginalized communities to advance their goals towards liberation.

Community Science as Resistance to Neoliberal Scientific Praxis.

Background: Flint is a site of resistance to neoliberalism specifically because of the actions of Flint residents. The impacts of this organizing are due, in part, to sustained efforts to reimagine how communities can contribute to scientific knowledge production. We argue that Flint residents' efforts to advance a community-driven research (CDR) agenda represent an important and successful resistance to neoliberal scientific regulatory practices. Methods: We present Flint as a case study in CDR as a form of resistance. This article uses participatory observation within community-based research and draws from the personal experiences of the research team as long-term and lifelong residents of Flint who were actively involved in different aspects of community mobilizing during the water crisis. Case Study: We highlight Flint's rich and sustained community-based participatory research history, resident-led data collection efforts to assess the environmental and health conditions, a resident-led effort to tell the story of the water crisis from the residents' perspective, and recent efforts to develop and advance a CDR model. Discussion: Community-led research efforts in Flint follow Leitner et al.'s typology of contesting neoliberalism through opting in to neoliberal science to advance community needs, collecting data to support direct opposition through protest and mobilization, creating alternative knowledge frames, and using CDR to disengage from the traditional scientific model. Conclusions: Through CDR, Flint residents work in direct resistance to the tacit integration of neoliberal values into science and alternatively advance community organizing as a key aspect of science toward environmental justice.

Advancing Equity Through Centering Societal Values to Operationalize Racism as a Public Health Crisis: The KKey Values Inequities Model.

Background: The past two decades have been marked by increased efforts to advance equity in various disciplines, including social sciences, public health, environmental health, and medicine. In 2020, a national movement of municipalities declared racism a public health crisis. These efforts have coincided and likely shaped a growing sphere of federal and philanthropic funding for health equity, which frequently calls for practical interventions toward reducing and ultimately eliminating disparities. Disparities in health such as maternal mortality, infant mortality, diabetes, cancer, and stroke have been linked to root causes such as racism. Often, root causes are also linked to disparities in other sectors (i.e., finance/wealth attainment, educational attainment, career attainment, and home ownership). In 2021, in a study published in the New England Journal of Medicine, suggested that racist policies were root causes of U.S. racial health inequities. While racism, sexism, and classism, etc., are characterized as root causes, we posit that there is a deeper driver that has yet to be advanced. This presents a disparity-inequity model that maps disparities and inequities to the societal value system, not root causes. Methods: The KKey Values Inequities Disparities Model described in this article combines a case study of the Flint Water Crisis to explore the historic impact of human devaluation and its role in systemic racism and classism, which ultimately creates and exacerbates inequities that produce disparities in communities. The model integrates the value system and its contribution to societal causes (formerly known as root causes). Conclusions: A broadly defined values-inequities-disparities model will allow researchers, practitioners, decision makers, lawmakers, and community members to (1) assess the core root of inequities and disparities; (2) identify solutions in the human value domain; (3) design appropriate course corrective programming, interventions, processes, and procedures; and (4) create actions to integrate new systemic procedures and practices in our laws and governance to advance equity.

Troubling heroes: Reframing the environmental justice contributions of the Flint water crisis.

While the story of the Flint water crisis has been shared widely, the popular narrative-described in multiple documentaries and as evidenced by accolades heaped upon a limited few number of actors involved with Flint-largely leaves out the broad experiences and actions of Flint residents in responding to the crisis, raising awareness, and advocating for change. Academic literature has contributed to reinforcing an abbreviated and disempowered version of the narrative where Flint residents needed rescue. In this article, we present an extended description of the Flint water crisis leading up to the water switch in April 2014, including descriptions of community mobilization efforts to call government actions into account and produce investigations that validated the concerns of the residents. We offer a review of prominent academic literature demonstrating patterns of erasure that suggest Flint residents were disempowered. In response, we offer three examples which demonstrate how Flint resident mobilizations have broad historical context, national reach, and individual actions that contradict the narrative that Flint residents lack agency and power. In our analysis, rather than viewing Flint residents as in need of rescue by science, we argue that the community mobilization in Flint is indicative of a highly successful implementation of popular epidemiology with profound effects on national conversations about lead in water, drinking water infrastructure management, and environmental justice.

Understanding and Enhancing Support Group Participation Among Adolescent and Young Adult Cancer Survivors: The Impact of Integrating Adolescent and Young Adult Cancer Navigation Services.

This quality improvement initiative aimed to (1) explore the impact of adolescent and young adult (AYA)-specific navigation on attendance at a monthly peer support group for survivors aged 18-39 at a large comprehensive cancer center, and (2) better understanding attendees' preferences for group structure. Group attendance significantly increased following integration of AYA navigation. Using an online survey, we identified priority topics for discussion and desired changes to group organization, leading to modifications to group structure. Results highlight the value of having dedicated staff who proactively orient patients to resources tailored to their unique needs, and the importance of flexible program development that incorporates stakeholder input.

In vitro assessment of mineral blocks as a cost-effective measure to reduce oral bioavailability of lead (Pb) in livestock.

Soil contamination in former mining districts is a persistent problem resulting from the historic lack of legal requirements as regards land restoration after mine closures. Much of this polluted land is currently being used worldwide for livestock and big game production, with the consequent health risks for the animals exposed and the subsequent threats to food safety. Soil remediation and restoration may be unfeasible or difficult to accomplish in the short term when pollution affects large territories and other alternatives must, therefore, be explored in order to reduce the probability of grazing animals being exposed to this contamination. In this paper, we study the use of mineral blocks (MBs) as a potential alternative by which to reduce the oral bioavailability of lead (Pb) in polluted soils by means of a simplified in vitro assay simulating gastrointestinal pH conditions. Experiments were carried out with twelve commercial MBs of different compositions in order to identify the most useful to be tested in further in vivo bioavailability studies. The results showed that one of them reduced the bioaccessibility of Pb from polluted soil by 88.2% and 75.9% under gastric and intestinal conditions, respectively, when compared with assays containing only polluted soil without MBs. The MB in question had the highest phosphorus content (7%) and one of the highest calcium contents (10%) of all those tested. Furthermore, negative correlations were detected between the content of calcium and phosphorus in the MBs and the percentage of bioaccessible Pb under gastric conditions, and between phosphorus and bioaccessible Pb under intestinal conditions. The use of MBs with a high phosphorus and calcium content should consequently be tested in vivo as a cost-effective (€ 0.6-1.5/sheep/month) tool by which to reduce the bioavailability of Pb for extensive grazing livestock reared in contaminated areas.

Understanding the Intrinsic and Extrinsic Motivations Associated with Community Gardening to Improve Environmental Public Health Prevention and Intervention.

Considering that community members continue to garden in and near environments impacted by pollutants known to negatively impact human health, this paper seeks to characterize the intrinsic and extrinsic motivations of a gardener and elucidate their perception of soil quality and environmental responsibility, awareness of past land use, and gardening behavior. Via semi-structured interviews with community gardeners in the Boston area (N = 17), multifactorial motivations associated with gardening as well as ongoing environmental health challenges were reported. Gardeners are knowledgeable about their garden's historical past and are concerned with soil quality, theft, trash maintenance, animal waste, and loss of produce from foraging animals. Study findings directly inform the field of environmental health exposure assessments by reporting gardening duration, activities that can lead to incidental soil ingestion, and consumption patterns of locally grown produce. This information combined with an understanding of a gardener's intrinsic and extrinsic motivations can be used to develop urban agricultural infrastructure and management strategies, educational programming, and place-based environmental public health interventions.

Tools for non-invasive sampling of metal accumulation and its effects in Mediterranean pond turtle populations inhabiting mining areas.

Among reptiles, freshwater turtle species have high potential for metal accumulation because of their long lifespan or their aquatic and terrestrial habits. In order to monitor metal bioaccumulation, determine potential toxic effects, and investigate tools for non-invasive metal sampling in reptiles, we studied lead (Pb) and mercury (Hg) accumulation in Mediterranean pond turtles (Mauremys leprosa) inhabiting two former mining areas, one of them with high environmental concentrations of Pb (Sierra Madrona-Alcudia Valley district) and the other one with high environmental concentrations of Hg (Almadén district). Individuals from the Pb mining area showed mean blood concentrations (i.e. 5.59 µg Pb/g dry weight, d.w.) that were higher than those measured in other populations. Blood Hg concentrations were highest (8.83 µg Hg/g d.w.) in the site close to the former Hg mines, whereas blood Hg concentrations in terrapins from another site of Almadén district, located ∼28 km downstream, were not different from locations at the non-mining area. Animals from the Pb-contaminated site showed evidence of oxidative stress, whereas those from the Hg-contaminated site showed increased activity of the antioxidant enzyme glutathione peroxidase, as well as reduced circulating levels of the main endogenous antioxidant peptide, glutathione. Concentrations measured in feces and carapace scutes were useful indicators to monitor blood concentrations of Pb, but not of Hg. Our results provide evidence of the usefulness of freshwater turtles as sentinels of chronic metal pollution, and validate non-invasive tools to advance Pb monitoring in reptiles.

Changes in U.S. medical students' specialty interests over the course of medical school.

BACKGROUND: Studies have examined factors affecting medical students' specialty choice, but little research exists on stability of these specialty interests. OBJECTIVE: To describe patterns of change in specialty interests during medical school and examine associations between specialty change patterns and gender, desire for a high-prestige career, and interest in prevention. DESIGN: Medical students (Class of 2003) at 15 representative US schools were invited to complete surveys during freshman orientation, entry to wards, and senior year. PARTICIPANTS: This analysis used data from 942 students who completed all 3 surveys. MEASUREMENTS: In addition to a number of other items, students were asked to choose the 1 specialty they were most interested in pursuing. RESULTS: The most common specialty choices among freshman students were pediatrics (20%) and surgery (18%); least common choices were psychiatry and preventive medicine (1% each). General internal medicine was the initial specialty choice for 8%. Most students changed their specialty choices, regardless of initial interest. Only 30% of those initially interested in primary care (PC) remained interested at all 3 time points, compared to 68% of those initially interested in non-PC. Female versus male students were more commonly interested in PC at all 3 time points. Senior students interested in non-PC specialties were more likely to desire a high-prestige career (48%) than those interested in PC (31%). CONCLUSIONS: Medical students may benefit from more intensive introduction to some specialties earlier in pre-medical and medical education. In addition, increasing the prestige of PC fields may shape the physician workforce.

Physical activity levels and counseling practices of U.S. medical students.

INTRODUCTION: Some literature shows a positive relationship between physicians' personal physical activity (PA) levels and physicians' encouraging patients' PA, though it remains unclear how this evolves during medical training. In this paper, we describe U.S. medical students' PA levels and factors predicting relevance and frequency of their PA counseling of patients. METHODS: This is a prospective survey of a representative sample of U.S. medical students from 16 schools (N = 2316) designed to determine health-related attitudes and practices. Student's PA levels were assessed using a Godin exercise questionnaire. An 80.3% (N = 1658) response rate was achieved during 4 yr. RESULTS: More than half (61%) of U.S. medical students adhered to CDC PA recommendations. This rate was relatively stable during the 4 yr of medical training. Of those who reported a lot of stress in the last 12 months or 2 wk, fewer than 60% complied with the CDC exercise recommendations, compared with at least 80% who reported almost no stress. Frequency of PA counseling of patients was consistently related to personal PA practices. The percent of students perceiving that PA counseling would be highly relevant to their practices decreased during the 4 yr of medical school, from 69 to 53% (P < 0.01). DISCUSSION: Among U.S. medical students, personal PA levels are higher than those of age-matched peers in the general population, are maintained throughout medical school, and are correlated with frequency of PA counseling of their patients. Promotion of adequate PA habits during medical education may be an important step to improve the PA preventive counseling that future clinicians provide.

Stress and depressive symptoms/dysphoria among US medical students: results from a large, nationally representative survey.

This study determined rates and correlates of stress, depressive symptoms/dysphoria, and suicidal thoughts among US medical students. Data were obtained from a large-scale survey conducted at 16 representative medical schools. Students completed questionnaires during first-year orientation (n= 1846), at the time of transition to clinical rotations (n= 1630), and during the fourth year (n= 1469). Students entering the wards reported greater stress, more bad mental health days, and greater depressive feelings than first-year students, with fourth-year students reporting intermediate stress levels. The number of days of bad mental health in the past month, stress experienced in the past 12 months, and perceptions about the medical school's system for coping were independently associated with suicidal thoughts, which were reported by 9% of fourth-year students. Medical schools should undertake efforts to assist students' coping because a substantial proportion of students experience meaningful levels of stress, depressive symptoms (especially around the time of transitioning to clinical care rotations), and suicidal thoughts.

Learning amid controversy: prostate cancer knowledge and screening practices among US medical students.

BACKGROUND: No studies have examined medical students' recommendation and use of prostate-specific antigen (PSA) testing and digital rectal exam (DRE) to screen for prostate cancer. We hypothesized that students' race and extent of training on these techniques would be associated with their administration of them. METHODS: We analyzed multiinstitutional longitudinal data from a cohort of 2181 medical students in the class of 2003. We queried students' health behavior, their knowledge of prostate cancer racial disparities, their frequency of performing a PSA test or a DRE on a man 50 years of age or older (senior year only), the perceived relevance of such services to their future practice, and their training on PSA and DRE. We examined predictors of students' administering PSA and DRE tests to patients during the senior year and changes in the predictors over time. RESULTS: Respectively, 27% and 34% of students reported using the PSA and DRE "usually/always" during their senior year. Black students reported administering the PSA test more often than did students of other races, but race was not a significant predictor of PSA screening after controlling for personal healthy behavior. High perceived relevance to future practice and extensive training on PSA were most strongly associated with administration of PSA. CONCLUSIONS: The association between healthy personal behavior and PSA administration confounded the association between race and PSA screening. These results may help explain differences in prostate cancer screening among physicians and help medical educators tailor their curricula on prostate cancer screening.