Nitrogen pollution in urban watersheds presents significant risks to both ecological health and human health by driving eutrophication and a cascade of related environmental issues. This study established and applied a comprehensive nitrogen risk assessment model to Marion County, Indiana, part of the Upper White River Watershed, to quantify and evaluate the sources and impacts of nitrogen pollution at the county and census tract level. Utilizing this data, the model comprehensively mapped nitrogen outputs from the following sources: electricity, fertilizer, food production and waste, natural gas, pet food and waste, transportation, and wastewater. The findings from 2019 revealed that the total nitrogen footprint of Marion County amounted to approximately 73.8 million kg of nitrogen, with the predominant contributions stemming from food production and waste (56%) and the energy sector (37%). These sectors highlight key areas where interventions can significantly reduce nitrogen outputs. The interactive web application developed alongside the model serves as a dynamic tool for stakeholders, enabling visualization distribution of nitrogen output, thereby supporting targeted policymaking and fostering community engagement in nitrogen management practices. By offering a detailed and scalable nitrogen assessment framework, this study contributes to the strategic planning necessary for sustainable urban development and environmental stewardship in rapidly urbanizing areas.
Water quality in urban streams is critical for the health of aquatic and human life, as it impacts both the environment and water availability. The strong impacts of changing climate and land use on water quality necessitate a better understanding of how stream water quality changes over space and time. To this end, four key water-quality parameters—Escherichia coli (E. coli), nitrate (NO3−), sulfate (SO42−), and chloride (Cl−)—were collected at 12 sites along Fall Creek and Pleasant Run streams in Indianapolis, Indiana USA from 2003 to 2021 on a seasonal basis: March, July, and October each year. Two-way ANOVA tests were used to determine the impacts of seasonality and location on these parameters. Correlation and RDA (redundancy analysis) were used to determine the importance of climatic drivers. Linear regressions were used to quantify the impacts of land-use types on water quality integrating buffer zone size and sub-watershed analysis. Strong seasonal variations of the water-quality parameters were found. March had higher levels of NO3−, SO42−, and Cl− than other months. July had the highest E. coli concentrations compared to March and October. Seven-days antecedent snow and precipitation were found to be significantly related to Cl− and log10(E. coli) and can explain up to 53% and 31% of their variations, respectively. Spatially, urban built-up land in a 1000 m buffer around the sampling sites was positively correlated with the log10(E. coli) variation, while lawn cover was positively related to NO3− concentrations within 500 m buffers. Conversely, NDVI (Normalized Difference Vegetation Index) values were negatively related to all variables. In conclusion, E. coli is more impacted by higher precipitation and urban land coverage, which could be related to more combined sewer overflow events in July. Cl− peaking in March and its relationship with snow indicate salt runoff during snow melting events. NO3− and SO42− increases are likely due to fertilizer input from residential lawns near streams. This suggests that Indianapolis stream water-quality changes are influenced by both changing climate and land-cover/-muse types.
Wetlands provide many ecosystem services, such as mitigating pollution, attenuating flooding and drought extremes, and providing habitat for many species. However, studies quantifying potential wetland sequestration of heavy metals as an ecosystem service, particularly across large spatial extents, are sparse. We utilized data from the United States Environmental Protection Agency’s National Wetland Condition Assessment to estimate anthropogenic metal (Pb, Cu, Cr) storage in the upper 40 cm of wetland soils across the conterminous United States—never done before at this scale. Large amounts of anthropogenic Cu and Cr are stored in wetland soil across the conterminous United States, at 299.5 ± 73.2 (95
Fine particulate matter (PM2.5) poses substantial urban health risks that vary across space, time, and population vulnerability. We integrate a spatio-temporal INLA–SPDE PM2.5 field with an agent-based model (ABM) of 10,000 daily home–work commuters in Indianapolis’s Pleasant Run airshed (50 weeks; 250 m grid). The PM2.5 surface fuses 23 corrected PurpleAir PA-II-SD sensors with meteorology, land use, road proximity, and MODIS AOD. Validation indicated strong agreement (leave-one-out R2 = 0.79, RMSE = 3.5 μg/m3; EPA monitor comparison R2 = 0.81, RMSE = 3.1 μg/m3). We model a spatial-equity counterfactual by assigning susceptibility independently of residence and workplace, isolating vulnerability from residential segregation. Under this design, annual PM2.5 exposure was statistically indistinguishable across groups (16.22–16.29 μg/m3; max difference 0.07 μg/m3, <0.5%), yet VWDI differed by ~10× (High vs. Very Low). Route-level maps reveal recurrent micro-corridors (>20 μg/m3) near industrial zones and arterials that increase within-group variability without creating between-group exposure gaps. These findings quantify a policy-relevant “floor effect” in environmental justice: even with perfect spatial equity, substantial health disparities remain driven by susceptibility. Effective mitigation, therefore, requires dual strategies—place-based emissions and mobility interventions to reduce exposure for all, paired with vulnerability-targeted health supports (screening, access to care, indoor air quality) to address irreducible risk. The data and code framework provides a reproducible baseline against which real-world segregation and mobility constraints can be assessed in future, stratified scenarios.
Although half of Earth's population resides in the wildland-urban interface, human exposure to wildland fires remains unquantified. We show that the population directly exposed to wildland fires increased 40% globally from 2002 to 2021 despite a 26% decline in burned area. Increased exposure was mainly driven by enhanced colocation of wildland fires and human settlements, doubling the exposure per unit burned area. We show that population dynamics accounted for 25% of the 440 million human exposures to wildland fires. Although wildfire disasters in North America, Europe, and Oceania have garnered the most attention, 85% of global exposures occurred in Africa. The top 0.01% of fires by intensity accounted for 0.6 and 5% of global exposures and burned area, respectively, warranting enhanced efforts to increase fire resilience in disaster-prone regions.
AGU and ASM welcome submissions to a joint special collection focusing on the impacts of climate change and microbes on human well-being.
BACKGROUND:This study investigated per- and polyfluoroalkyl substances (PFASs) in 53 fruit and vegetable samples collected from a local wholesale and retail market in Sydney and a local supermarket in Newcastle. As there is limited information about PFAS levels in vegetables on the market, this study aimed to fill this gap and assess potential risks for humans through consumption of these vegetables. METHODS:QuEChERS extraction - a solid-phase extraction method, a portmanteau word formed from 'quick, easy, cheap, effective, rugged and safe' - followed by enhanced matrix removal-lipid cleaning and liquid chromatography-tandem mass spectrometry analysis were used to detect 30 PFASs in vegetables. RESULTS:PFOA was detected in 7 out of the 53 samples, with concentrations of 0.038-1.996 ng g-1 fresh weight; PFOS was detected in 2 samples only, with concentrations ranging from 0.132 to 0.911 ng g-1 fresh weight. PFHxS was not detected in any sample in this study. PFOA and PFOS concentrations measured in vegetables in this study constituted daily intake of 2.03 ng kg-1 body weight (BW) and 1.98 ng kg-1 BW, respectively, according to recommended daily vegetable intake and BW data from the Australian Bureau of Statistics. The most sensitive population group is girls of 4-8 years of age. These estimated exposure levels represent up to 1.3% of the tolerable daily intake for PFOA (160 ng kg-1 BW) and 9.9% for PFOS (20 ng kg-1 BW) according to Food Standards Australia New Zealand. Consumption of the vegetables from the study locations poses a marginal risk to human health. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
Peer-review is the foundation and the safeguard of scientific research. Without the dedication of our reviewers, the journal would not have been successful. In 2023, 269 reviewers completed 434 reviews for the 174 manuscripts submitted to GeoHealth. Our reviewers are from all continents except Antarctica. Besides reviewers from North America, China, Europe, and China, we started to have reviewers from India, Latin America, and Africa. GeoHealth editorial board is committed to expanding the readership, authorship, and reviewership to other countries. If you have already reviewed for us, no matter where or who you are, we hope you and your colleagues will consider GeoHealth a home for your work. Below is the list of reviewers who completed more than two reviews or have outstanding quality reviews. Two of our reviewers are being nominated for AGU best reviewers awards.
This study introduces a novel hybrid model combining Bayesian Stochastic Partial Differential Equations (SPDE) with deep learning, specifically Convolutional Neural Networks (CNN) and Deep Feedforward Neural Networks (DFFNN), to predict PM2.5 concentrations. Traditional models often fail to account for non-linear relationships and complex spatial dependencies, critical in urban settings. By integrating SPDE’s spatial-temporal structure with neural networks’ capacity for non-linearity, our model significantly outperforms standalone methods. Accurately predicting air pollution supports sustainable public health strategies and targeted interventions, which are critical for mitigating the adverse health effects of PM2.5, particularly in urban areas heavily impacted by climate change. The hybrid model was applied to the Pleasant Run Airshed in Indianapolis, Indiana, utilizing a comprehensive dataset that included PM2.5 sensor data, meteorological variables, and land-use information. By combining SPDE’s ability to model spatial-temporal structures with the adaptive power of neural networks, the model achieved a high level of predictive accuracy, significantly outperforming standalone methods. Additionally, the model’s interpretability was enhanced through the use of SHAP (Shapley Additive Explanations) values, which provided insights into the contribution of each variable to the model’s predictions. This framework holds the potential for improving air quality monitoring and supports more targeted public health interventions and policy-making efforts.
The outgoing and incoming Editors in Chief of GeoHealth reflect on recent years of growth and expansion in the journal while they plan for the challenges ahead.
Lead exposure has blighted communities across the United States (and the globe), with much of the burden resting on lower income communities, and communities of color. On 17 January 2024, the US Environmental Protection Agency (USEPA) lowered the recommended screening level of lead in residential soils from 400 to 200 parts per million. Our analysis of tens of thousands of citizen-science collected soil samples from cities and communities around the US indicates that nearly one quarter of households may contain soil lead that exceed the new screening level. Extrapolating across the nation, that equates to nearly 30 million households needing to mitigate potential soil lead hazards, at a potential total cost of 290 billion to $1.2 trillion. We do not think this type of mitigation is feasible at the massive scale required and we have instead focused on a more immediate, far cheaper strategy: capping current soils with clean soils and/or mulch. At a fraction of the cost and labor of disruptive conventional soil mitigation, it yields immediate and potentially life-changing benefits for those living in these environments.
Lead exposure has blighted communities across the United States (and the globe), with much of the burden resting on lower income and communities of color. On January 17, 2024, the US Environmental Protection Agency (USEPA) has, after more than 30 years, lowered the allowable level of lead in residential soils. Our analysis of tens of thousands of citizen-science collected soil samples from cities and communities around the US reveals the scale of the soil lead problem, and the challenge that the USEPA will face in implementing its new soil standard. Under this standard, we find that nearly one quarter of households may contain a soil lead hazard. Extrapolating across the nation, that equates to nearly 30 million households needing to mitigate potential soil lead hazards, at a potential total cost of $290 billion to - $1.2 trillion. We do not think this type of mitigation is feasible at the massive scale required and we have instead focused on a more immediate, far cheaper strategy: capping current soils with clean soils and/or mulch. At a fraction of the cost and labor of disruptive conventional soil mitigation, it yields immediate and potentially life-changing benefits for those living in these environments.
INTRODUCTION:Exposure to ambient air pollution is strongly associated with increased cerebrovascular diseases. The 2019-20 bushfire season in Australia burnt 5.4 million hectares of land in New South Wales alone, with smoke so severe it affected cities in Argentina, 11,000 km away. The smoke emitted by bushfires consists of both gaseous and particle components. It is important to note that exposure to particulate matter has been shown to be linked to a heightened risk of stroke, which is the primary kind of cerebrovascular illness, as well as an increased likelihood of hospitalisations and mortality. However, the available data is inadequate in terms of documenting the response of patients diagnosed with a proven cerebrovascular illness to bushfire smoke. Additionally, there is a lack of information about the health effects associated with particulate matter throughout the bushfire season and on days when smoke was present in 2019 and 2020.Therefore, we aimed to determine the effects of (i) short-term air pollution triggered by bushfires and (ii) high smoke days in increasing the daily number of hospital admissions with cerebrovascular diseases. MATERIALS AND METHODS:Hospitalisation data were accessed from the admitted patient dataset from seven local Government areas of Hunter New England Local Health District. The bushfire period was defined from 1 October 2019 to 10 February 2020, and a same period from 2018-19 as the control. High bushfire smoke days were days when the average daily concentration of particulate matter was higher than the 95th percentile of the control period. Poisson regression models and fixed effect meta-analysis were used to analyse the data. RESULTS:In total, 275 patients with cerebrovascular admissions were identified, with 147 (53.5%) during the bushfire (2019-20) and 128 (46.5%) in the control period (2018-19). There was no significant increase in daily admissions for cerebrovascular disease (Incidence Rate Ratio, IRR: 1.04; 95% CI: 0.81-1.34; p-value: 0.73), acute stroke (IRR: 1.15; 95% CI: 0.88-1.50; p-value: 0.29) or acute ischaemic stroke (IRR: 1.18; 95% CI: 0.87-1.59; p-value: 0.28), over the entire bushfire period. However, the high bushfire smoke days were associated with increased acute ischaemic stroke-related hospital admissions across lead 0-3 and the highest cumulative effect was observed with lead 0 (IRR:1.52; 95% CI: 1.01-2.29; p-value: 0.04). In addition, during the bushfire period, particulate matter, both PM10 and PM2.5 (defined as particulates that have an effective aerodynamic diameter of 10, and 2.5 microns, respectively), were also associated with increased acute ischaemic stroke admissions with a lag of 0-3 days. DISCUSSION AND CONCLUSION:The results suggested a possible association between particulate matter and high smoke days with increased hospital admissions due to acute ischaemic stroke during the recent Australian bushfire season.
The main sources of lead exposure for children occur in the home environment, yet no low-cost analytical methods exist to screen homes for lead hazards. Previously, an inexpensive (~$20), quantitative lead screening kit was developed in which residents collect soil, paint, and dust samples that are returned to a laboratory for lead analysis using X-ray fluorescence spectroscopy (XRF). This screening kit was initially validated in 2020; it was determined that in situ and ex situ XRF lead measurements on the same samples exhibited strong sensitivity, specificity, and accuracy. As a follow-up to the initial validation, an implementation study and further statistical analyses were conducted. Correlation analysis using the results from nearly 400 screening kits identified an overall lack of correlation between sample types, reinforcing the utility of all eight sample locations. Principal component analysis searched for underlying correlations in sample types and provided evidence that both interior and exterior paint are major sources of lead hazards for Indiana homes. The implementation study compared the results of the government-standard lead inspection and risk assessment (LIRA) and the lead screening kit in 107 Indiana homes. In the United States, the LIRA is a thorough inspection of paint, dust, and soil that is usually state mandated in response to a child's elevated blood level and is used to identify where remediation efforts should be focused. The lead screening kit and LIRA agreed on the presence of lead in 79 of the 107 homes tested (74%). Discrepancies in agreement are likely the result of differences in the sample location and number of samples collected by each method. Overall, these results suggest that the lead screening kit is an acceptable resource that could be used to expand the services health departments provide for lead prevention. Integr Environ Assess Manag 2024;20:1504-1513. © 2024 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).