Environmental manganese exposure has been associated with adverse neurodevelopmental outcomes among school-aged children; yet, few studies have evaluated prenatal exposure.
Our study examines ...associations between prenatal manganese concentrations and placental transfer of manganese with neurodevelopment in 224 2-y-old children residing near the Tar Creek Superfund Site.
We collected maternal and cord blood at delivery, measured manganese using inductively coupled plasma mass spectrometry, and assessed neurodevelopment using the Bayley Scales of Infant Development-II. Associations between manganese and mental (MDI) and psychomotor (PDI) development indices were estimated in multivariable models. Placental transfer, approximated by cord/maternal manganese ratio, cord/total manganese ratio (total=maternal+cord), and by joint classification according to high or low (above or below median) maternal and cord manganese, was evaluated as a predictor of neurodevelopment.
Median levels interquartile ranges (IQR) of manganese in maternal and cord blood, respectively, were 24.0 (19.5-29.7) and 43.1 (33.5-52.1) μg/L. Adjusting for lead, arsenic, and other potential confounders, an IQR increase in maternal manganese was associated with -3.0 (95% CI: -5.3, -0.7) points on MDI and -2.3 (95% CI: -4.1, -0.4) points on PDI. Cord manganese concentrations were not associated with neurodevelopment scores. Cord/maternal and cord/total manganese ratios were positively associated with MDI cord/maternal: β=2.6 (95% Cl: −0.04, 5.3); cord/total: β=22.0 (95% Cl: 3.2, 40.7) and PDI (cord/maternal: β=1.7 (95% Cl: −0.5, 3.9); cord/total: β=15.6 (95% Cl: 0.3, 20.9)). Compared to mother-child pairs with low maternal and cord manganese, associations with neurodevelopment scores were negative for pairs with either high maternal, high cord, or high maternal and cord manganese.
Maternal blood manganese concentrations were negatively associated with early childhood neurodevelopment scores in our study. Findings highlight the importance of understanding maternal exposures during pregnancy and factors influencing placental transfer. https://doi.org/10.1289/EHP925.
A pilot study was conducted to explore the potential associations between hair metal levels and the neuropsychological function and behavior of school-aged children. Thirty-two children, 11–13 years ...old, were administered a battery of tests that assessed general intelligence, visual-motor skills, receptive language, verbal memory, nonverbal problem-solving, and behavior problems. Parents and teachers rated the children's attention, executive functions, and behavior problems. The concentrations of manganese (Mn), arsenic (As), and cadmium (Cd) were measured in hair samples provided by 31 of the children. The mean hair metal levels were: Mn, 471.5 parts per billion (ppb); As, 17.8
ppb; Cd, 57.7
ppb. Children's general intelligence scores, particularly verbal IQ scores, were significantly related, inversely, to hair Mn and As levels, as were scores on tests of memory for stories and a word list. In some cases, a significant Mn-by-As interaction was found. It appeared that it was the low scores of children for whom both Mn and As levels were above the median values in the sample that were responsible for the main effects observed for each metal. No other significant relationships were found. These results suggest the need to study further the neuropsychological correlates of developmental exposure to Mn and As, particularly as a mixture.
GeoHealth as a research paradigm offers the opportunity to re‐evaluate common research engagement models and science training practices. GeoHealth challenges are often wicked problems that require ...both transdisciplinary approaches and the establishment of intimate and long‐term partnerships with a range of community members. We examine four common modes of community engagement and explore how research projects are launched, who has the power in these relationships, and how projects evolve to become truly transformative for everyone involved.
Plain Language Summary
GeoHealth research is often partnership focused. We describe four common models for community‐engaged GeoHealth research and highlight the central characteristics of each, while daylighting the lived experiences of LEAD Agency activists. We note a range of outcomes emerge which can foster science‐based environmental health policy making and lead to justice focused actions.
Key Points
The GeoHealth research community often engages actively with civil society in the research enterprise, but often uses various models
The models of engagement, from researcher‐heavy to community‐heavy, have very different outcomes
A new model of training and support is required for the GeoHealth community to more productively engage with civil society
Methylmercury (MeHg) exposure through fish consumption is a worldwide health concern. Saltwater fish account for most dietary MeHg exposure in the general U.S. population, but less is known about ...seasonal variations in MeHg exposure and fish consumption among millions of freshwater anglers. This longitudinal study examined associations between MeHg exposure and fish consumption in a rural, low-income population relying on a freshwater reservoir (Oklahoma, USA) for recreational and subsistence fishing. We interviewed 151 participants, primarily anglers and their families, seasonally for one year using 90-day recall food frequency questionnaires to assess general and species-specific fish consumption, and tested hair biomarker samples for total mercury (THghair). Mean THghair was 0.27μg/g (n=595, range: 0.0044–3.1μg/g), with 4% of participants above U.S. EPA's guideline for women of childbearing age and children. Mean fish consumption was 58g/d (95% CI: 49–67g/d), within the range previously reported for recreational freshwater anglers and above the national average. Unlike the general U.S. population, freshwater species contributed the majority of fish consumption (69%) and dietary Hg exposure (60%) among participants, despite relatively low THg in local fish. THghair increased with fish consumption, age, and education, and was higher among male participants and the lowest in winter. Our results suggest that future studies of anglers should consider seasonality in fish consumption and MeHg exposure and include household members who share their catch. Efforts to evaluate benefits of reducing Hg emissions should consider dietary patterns among consumers of fish from local freshwater bodies.
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•We assessed fish consumption and hair Hg in freshwater anglers and their families.•Hair Hg increased with higher fish consumption rate, age, and education.•Majority of fish and Hg intake came from local freshwater fish despite low fish Hg.•Fish consumption rates and hair Hg showed some seasonal variation.•Women ate more fish per unit body weight but had lower Hg intake relative to men.
This article examines Indigenous perspectives on crises, empowerment, justice and resurgence through a case study of Indigenous-led Toxic Tours in the state of Oklahoma, US across both Native and ...non-Native lands that have been severely polluted. The Tar Creek Superfund Site and Grand Lake watershed comprise an interconnected water and land ecosystem that has been severely contaminated as a result of 20
th
century lead and zinc mining in the region. This mining legacy has resulted in extreme toxic assaults to water, soil, air, animal and plant life, as well as to human health, cultural lifeways, livelihoods and wellbeing. Through the vehicle of Tar Creek and Grand Lake/Downstream Impacts Toxic Tours led by the community-based organization, LEAD Agency, numerous visitors have been able to witness and engage with these impacted lands, waterscapes, communities, Tribal Nations and non-human living beings over decades. Using an autoethnographic approach to bring forward the perspectives of LEAD co-founders and Toxic Tour guides, Rebecca Jim and Earl Hatley, this research critically explores the ways in which these tours engage with empowerment, justice and resurgence discourses, while centering Indigenous perspectives on the crisis. While the insights and perspectives offered by Rebecca and Earl point to a strong connection between Toxic Tours and their capacity for engaging with empowerment, justice and Indigenous-led resurgence, the analysis of these reflections also point to differences between these discourses and their approach to crises, with resurgence discourses offering unique Indigenous conceptualizations of crisis, priorities and the ways forward.
Home to nine Tribal Nations, the northeastern corner of Oklahoma (US) is a place of immense resilience, cultural beauty and attachment to place. Horrifically, however, this same area is also home to ...massive environmental assaults that have occurred as a result of decades of lead and zinc mining. The improperly managed mine waste that has accumulated since the late 1800s now severely contaminates the water, land and air, having adverse impacts on the health of the ecosystem and the local human community alike. Leading the fight for cleanup and support of place and people since 1997 is the non-profit organisation called Local Environmental Action Demanded (LEAD Agency). One of LEAD’s primary tools for education and advocacy has been leading toxic tours across these harmed lands and waters. This contribution draws upon the nearly three decades of toxic tours that Rebecca and Earl have led by sharing key stories and experiences of important sites visited along the way, offering a snapshot of toxic tour experience. Drawing on Indigenous storywork and autoethnographic methodologies, this contribution aims to spotlight the potential of Indigenous-led toxic tours for helping to (re)connect people — both locals and visitors — to place and a responsibility of stewardship.
Limited epidemiologic data exist on prenatal arsenic exposure and fetal growth, particularly in the context of co-exposure to other toxic metals.
We examined whether prenatal arsenic exposure ...predicts birth outcomes among a rural U.S. population, while adjusting for exposure to lead and manganese.
We collected maternal and umbilical cord blood samples at delivery from 622 mother-infant pairs residing near a mining-related Superfund site in Northeast Oklahoma. Whole blood arsenic, lead, and manganese were measured using inductively coupled plasma mass spectrometry. We modeled associations between arsenic concentrations and birth weight, gestational age, head circumference, and birth weight for gestational age.
Median (25th-75th percentile) maternal and umbilical cord blood metal concentrations, respectively, were as follows: arsenic, 1.4 (1.0-2.3) and 2.4 (1.8-3.3) μg/L; lead, 0.6 (0.4-0.9) and 0.4 (0.3-0.6) μg/dL; manganese, 22.7 (18.8-29.3) and 41.7 (32.2-50.4) μg/L. We estimated negative associations between maternal blood arsenic concentrations and birth outcomes. In multivariable regression models adjusted for lead and manganese, an interquartile range increase in maternal blood arsenic was associated with -77.5 g (95% CI: -127.8, -27.3) birth weight, -0.13 weeks (95% CI: -0.27, 0.01) gestation, -0.22 cm (95% CI: -0.42, -0.03) head circumference, and -0.14 (95% CI: -0.24, -0.04) birth weight for gestational age z-score units. Interactions between arsenic concentrations and lead or manganese were not statistically significant.
In a population with environmental exposure levels similar to the U.S. general population, maternal blood arsenic was negatively associated with fetal growth. Given the potential for relatively common fetal and early childhood arsenic exposures, our finding that prenatal arsenic can adversely affect birth outcomes is of considerable public health importance.
Claus Henn B, Ettinger AS, Hopkins MR, Jim R, Amarasiriwardena C, Christiani DC, Coull BA, Bellinger DC, Wright RO. 2016. Prenatal arsenic exposure and birth outcomes among a population residing near a mining-related Superfund site. Environ Health Perspect 124:1308-1315; http://dx.doi.org/10.1289/ehp.1510070.
Atmospheric dispersion of particles from mine waste is potentially an important route of human exposure to metals in communities close to active and abandoned mining areas. This study assessed ...sources of mass and metal concentrations in two size fractions of respirable particles using positive matrix factorization (U.S. Environmental Protection Agency EPA PMF 3.0). Weekly integrated samples of particulate matter (PM) 10 µm in aerodynamic diameter or less (PM
10
) and fine PM (PM
2.5
, or PM <2.5 µm in aerodynamic diameter) were collected at three monitoring sites, varying distances (0.5-20 km) from mine waste piles, for 58 consecutive weeks in a former lead (Pb) and zinc (Zn) mining region. Mean mass concentrations varied significantly across sites for coarse PM (PM
10
-PM
2.5
) but not PM
2.5
particles. Concentrations of Pb and Zn significantly decreased with increasing distance from the mine waste piles in PM
10
-PM
2.5
(P < 0.0001) and PM
2.5
(P < 0.0005) fractions. Source apportionment analyses deduced five sources contributing to PM
2.5
(mobile source combustion, secondary sulfates, mine waste, crustal/soil, and a source rich in calcium Ca) and three sources for the coarse fraction (mine waste, crustal/soil, and a Ca-rich source). In the PM
2.5
fraction, mine waste contributed 1-6% of the overall mass, 40% of Pb, and 63% of Zn. Mine waste impacts were more apparent in the PM
10
-PM
2.5
fraction and contributed 4-39% of total mass, 88% of Pb, and 97% of Zn. Percent contribution of mine waste varied significantly across sites (P < 0.0001) for both size fractions, with highest contributions in the site closest to the mine waste piles. Seasonality, wind direction, and concentrations of the Ca-rich source were also associated with levels of ambient aerosols from the mine waste source. Scanning electron microscopy results indicated that the PMF-identified mine waste source is mainly composed of Zn-Pb agglomerates on crustal particles in the PM
10
-PM
2.5
fraction. In conclusion, the differential impacts of mine waste on respirable particles by size fraction and location should be considered in future exposure evaluations.
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