Environmental Protection Agency Research Articles

Assessment of the surface water quality and primary health risk in urban wastewater and its receiving river Kathajodi, Cuttack of eastern India.

Kathajodi, the principal southern distributary of the Mahanadi River, is the vital source of irrigation and domestic water use for densely populated Cuttack city which receives anthropogenic wastes abundantly. This study assesses the contamination level and primary health status of urban wastewater, and its receiving river Kathajodi based on the physicochemical quality indices employing inductively coupled plasma mass spectroscopy and aligning with guidelines from the United States Environmental Protection Agency (USEPA) and WHO. The high WQI, HPI, and HEI in the catchment area (KJ2, KJ3, and KJ4) indicate poor water quality due to the influx of domestic waste through the primary drainage system and effluents of healthcare units. A high BOD (4.33-19.66mg L-1) in the catchment indicates high organic matter, animal waste, bacteriological contamination, and low DO, resulting in deterioration of water quality. CR values beyond limits (1.00E - 06 to 1.00E - 04) in three locations of catchment due to higher Cd, Pb, and As indicate significant carcinogenic risk, while high Mn, Cu, and Al content is responsible for several non-carcinogenic ailments and arsenic-induced physiological disorders. The elevated heavy metals Cd, Cu, Fe, Mn, Ni, and Zn, in Kathajodi, could be due to heavy coal combustion, vehicle exhaust, and industrial waste. On the other hand, Cu, Fe, K, and Al could be from agricultural practices, weathered rocks, and crustal materials. Positive significant (p ≤ 0.05) Pearson correlations between physicochemical parameters indicate their common anthropogenic origin and similar chemical characteristics. A strong correlation of PCA between elements and physiological parameters indicates their role in water quality deterioration. Assessing the surface water quality and heavy metal contents from this study will offer critical data to policymakers for monitoring and managing public health concerns.

Underestimation of Thermogenic Methane Emissions in New York City.

Recent studies have shown that methane emissions are underestimated by inventories in many US urban areas. This has important implications for climate change mitigation policy at the city, state, and national levels. Uncertainty in both the spatial distribution and sectoral allocation of urban emissions can limit the ability of policy makers to develop appropriately focused emission reduction strategies. Top-down emission estimates based on atmospheric greenhouse gas measurements can help to improve inventories and inform policy decisions. This study presents a new high-resolution (0.02 × 0.02°) methane emission inventory for New York City and its surrounding area, constructed using the latest activity data, emission factors, and spatial proxies. The new high-resolution inventory estimates of methane emissions for the New York-Newark urban area are 1.3 times larger than those for the gridded Environmental Protection Agency inventory. We used aircraft mole fraction measurements from nine research flights to optimize the high-resolution inventory emissions within a Bayesian inversion. These sectorally optimized emissions show that the high-resolution inventory still significantly underestimates methane emissions within the New York-Newark urban area, primarily because it underestimates emissions from thermogenic sources (by a factor of 2.3). This suggests that there remains a gap in our process-based understanding of urban methane emissions.

Enhanced detection of heavy metal ions using Ag nanoparticles and single-walled carbon nanotubes within Cu-based metal-organic frameworks

Heavy metal ions (HMIs) are major water pollutants, and their toxicity for humans is a great concern for scientists and environmentalists. They are harmful to health even at trace levels; therefore, identifying and removing heavy metals from water is critical. Herein, we report highly selective and sensitive multi-analyte detection of HMIs in water using an electrochemical sensor probe based on Ag nanoparticles and single-walled carbon nanotubes incorporating copper benzene tri-carboxylate metal–organic frameworks (Ag/SWNTs@CuBTC-MOFs). The materials were characterized using FTIR, XPS, XRD, and FE-SEM with EDX mapping, TEM, TG-DTA, BET surface area, CV, and EIS. The Ag/SWNTs@CuBTC-MOF electrochemical sensor was tested by differential pulse voltammetry over a pH range of 3–10 for various HMIs. It shows high pH-dependent sensitivity towards Hg2+ (pH-5.0), Ni2+ (pH-7.0), and Fe3+ (pH-10.0) ions and a limit of detection of 1.39 nM, 2.6 nM, and 3.03 nM, respectively. The fabricated sensor probe exhibits high selectivity, good linearity, and a limit of detection below the maximum contamination limit, as the US Environmental Protection Agency suggested.

Exposure Experiences of Area Residents Near a Chronic Environmental Contamination Site

Background: The study aims to analyze and interpret the exposure experiences of local residents living within 5 miles of the Fernald Feed Materials Production Center, a former uranium processing site. The goal is to enhance public health efforts addressing psychological stress resulting from environmental exposure. Methods: Semi-structured interviews were conducted from July 1998 to February 2001 as part of the Fernald Living History Project. The study focuses on 4 key phenomenological events: air releases of uranium by-products, Ohio Environmental Protection Agency public notifications of water contamination, a citizens' class action lawsuit against the US Department of Energy and National Lead of Ohio, Inc, and extensive media coverage. Researchers used descriptive inductive coding to analyze data from these events, involving 34 participants. Results: The study identified 5 central themes in the residents' exposure experiences: disruptions to life, loss of trust, seeking answers, interpreting ambiguous threats, and adaptive responses. Participants recounted how these events affected their lives and triggered emotional responses. Conclusion: This research provides valuable insights into the experiences of individuals living near environmentally contaminated sites and offers guidance for future prevention and mitigation strategies.

An integrated uncrewed aerial vehicle platform with sensing and sampling systems for the measurement of air pollutant concentrations

Abstract. In this study, an uncrewed aerial vehicle (UAV) platform with sensing and sampling systems was developed for three-dimensional (3D) measurements of air pollutant concentrations. The sensing system of this platform contains multiple microsensors and Internet of Things devices for determining the 3D distributions of four critical air pollutants and two meteorological parameters in real time. Moreover, the sampling system comprises remote-controllable gas sampling kits, each of which contains a 1 L Tedlar bag for the 3D measurement of volatile organic compound (VOC) concentrations according to the Toxic Organics-15 (TO-15) method of the US Environmental Protection Agency. The performance of the developed UAV platform was verified in experiments where it was used to detect air pollutant emissions from a large industrial zone in Taiwan that included a traditional industrial park, a precision machinery park, and a municipal waste incineration plant. Three locations were selected as field measurement sites according to the prevailing local wind direction. The vertical distributions of four critical air pollutants, the ambient temperature, and the relative humidity were determined from data gathered at the aforementioned sites in March and May 2023. A total of 56 and 72 chemical species were qualitatively and quantitatively analyzed in these two periods, respectively. The experimental results verified the feasibility of using the proposed UAV platform for accurately evaluating the air pollutant concentration distribution and transport in an industrial zone. The sampling system can be used as the sampling part of the TO-15 method, thus extending the method to measure the 3D distribution of VOCs in an area. The UAV platform can serve as a useful tool in the management of and decision-making process for air pollution in industrial areas.

Radon Exposure Assessment in Occupational and Environmental Settings: An Overview of Instruments and Methods

Radon is a naturally occurring noble radioactive gas that poses significant health risks, particularly lung cancer, due to its colorless, odorless, and tasteless nature, which makes detection challenging without formal testing. It is found in soil, rock, and water, and it infiltrates indoor environments, necessitating regulatory standards and guidelines from organizations such as the Environmental Protection Agency, the World Health Organization, and the Occupational Health and Safety Agency to mitigate exposure. In this paper, we present various methods and instruments for radon assessment in occupational and environmental settings. Discussion on long- and short-term monitoring, including grab sampling, radon dosimetry, and continuous real-time monitoring, is provided. The comparative analysis of detection techniques—active versus passive—is highlighted from real-time data and long-term exposure assessment, including advances in sensor technology, data processing, and public awareness, to improve radon exposure evaluation techniques.

Environmental factors and daily suicides: a time series analysis

Background This study investigated the association between weather, air pollution, and suicide risk in Sousse. Methods A two-time series analysis examined suicide cases recorded in the forensic service of Farhat Hached University Hospital of Sousse, confirmed by autopsy, over seven years (2010-2016). Climate data were retrieved from the Monastir-Airport weather station, and air pollution data were obtained from the National Agency for Environmental Protection’s modelling platform. Results During the study period, 118 suicides were recorded, with the highest number (19.5%) occurring in 2012. Multiple binary logistic regression analysis revealed that autumn and a decline in NH3 were independently associated with a decreased risk of suicide (p=0.045; ORa: 0.57 CI95% [0.33-0.98], p= 0.009; ORa: 0.24 CI95% [0.08-0.71], respectively). Conversely, a 1 ppm increase in PM10 was associated with a 2.5% increase in suicide risk (p<10-3; ORa: 1.02 CI95% [1.01-1.03]). Conclusions Environmental factors, including seasonality and air quality, may provide valuable insights into suicide risks. Understanding the influence of these factors may have implications in preventive strategies.

Heavy Metal Ion Adsorbent in Aqueous Solution: A Review on Chitosan and Chitosan Composites

One prominent contributor to environmental degradation is the presence of heavy metal ions, which are commonly introduced into ecosystems through diverse channels, including mining operations, paint manufacturing, battery production, and agricultural practises. The unprocessed waste from these industries typically undergoes direct discharge into rivers and seas, thereby adversely influencing the potable water supply and marine ecosystem. This results in the accumulation of heavy metals within living organisms and subsequent environmental degradation that poses a significant risk to human health, as their prolonged consumption can harm various organs and the nervous system. Therefore, the United States Environmental Protection Agency (US-EPA) and the World Health Organisation (WHO) have established stringent regulations regarding the allowable levels of heavy metal intake, particularly concerning potable water consumption. The imperative lies in surmounting this challenge by discovering the optimal technique for extracting heavy metals. This paper examines the primary methods of eliminating heavy metal ions using chitosan-based materials. Specifically, the methods under scrutiny include electrocoagulation (E.C.), bioremediation, ion-exchange, membrane filtration (purification), and adsorption. Adsorption, as a highly efficient method, presents itself as a viable strategy for the remediation of dyes in textile wastewater due to its advantageous characteristics. Notably, this approach obviates the need for extensive spatial requirements and exhibits a commendably swift treatment duration. Chitosan exhibits promising adsorptive characteristics owing to its advantageous physical attributes, including crystalline structure, porous nature, and particle dimensions, all of which synergistically enhance the adsorption capacity of chitosan. Research findings indicate that the adsorption characteristics of chitosan are subject to variation contingent upon the distinct heavy metal ions under consideration and the specific experimental parameters employed. Hence, optimising these parameters becomes imperative to attain enhanced chitosan adsorption capabilities for heavy metal ion removal.

The application of PTR-MS and non-targeted analysis to characterize VOCs emitted from a plastic recycling facility fire.

On April 11th, 2023, the My Way Trading (MWT) recycling facility in Richmond, Indiana caught fire, mandating the evacuation of local residents and necessitating the U.S. Environmental Protection Agency (EPA) to conduct air monitoring. The EPA detected elevated levels of plastic combustion-related air pollutants, including hydrogen cyanide and benzene. We aimed to identify these and other volatile organic compounds (VOCs) present as well as to identify the potential hazard of each compound for various human health effects. To identify the VOCs, we conducted air monitoring at sites within and bordering the evacuation zone using proton transfer reaction mass spectrometry (PTR-MS) and non-targeted analysis (NTA). To facilitate risk assessment of the emitted VOCs, we used the EPA Hazard Comparison Dashboard. We identified 46 VOCs, within and outside the evacuation zone, with average detection levels above local background levels measured in Middletown, OH. Levels of hydrogen cyanide and 4 other VOCs were at least 1.8-fold higher near the incidence site in comparison to background levels and displayed unique temporal and spatial patterns. The 46 VOCs identified had the highest hazardous potential for eye and skin irritation, with approximately 45% and 39%, respectively, of the VOCs classified as high and very high hazards for these endpoints. Notably, all detected VOC levels were below the hazard thresholds set for single VOC exposures; however, hazard thresholds for exposure to VOC mixtures are currently unclear. This study serves as a proof-of-concept that PTR-MS coupled with NTA can facilitate rapid identification and hazard assessment of VOCs emitted following anthropogenic disasters. Furthermore, it demonstrates that this approach may augment future disaster responses to quantify additional VOCs present in complex combustion mixtures.

A survey of the radiation safety practices of veterinary practitioners during portable equine radiography in Ireland.

Veterinary practitioners and other personnel involved in the examination are exposed to ionizing radiation while performing portable radiographs on horses. An online survey was distributed to all Veterinary Council of Ireland-registered practices where the self-reported practice profile is at least 20% equine work. The survey contained questions relating to radiation safety training, protocols, personal dosimetry and lead protection usage, repeat exposures, sedation, and personnel roles during the examination. The aim of the survey was to document the current radiation safety practices of equine veterinary practitioners during portable radiography. The results showed that although adherence to guidance set out by the Environmental Protection Agency (EPA) is reasonably good, compliance rates can be improved. Personal dosemeter usage and repeat rate reduction could particularly benefit from further improvement. This is of the utmost importance in ensuring that occupational radiation exposure to veterinary practitioners is kept to an absolute minimum during their daily practice.

Revisiting the quantification of power plant CO2 emissions in the United States and China from satellite: A comparative study using three top-down approaches

Top-down constraints of CO2 emissions from coal-fired power plants are critical to improving the accuracy of CO2 emission inventory and designing carbon reduction strategies. Different top-down models based on satellite observation have been proposed in previous studies, but discrepancies between these models and the underlying drivers are rarely explored, limiting the confidence of their application for monitoring point-source CO2 emissions from satellite. Here, we apply three top-down models to estimate CO2 emissions from individual coal-fired power plants in the United States (US) and China in 2014–2021 from Orbiting Carbon Observatory 2 (OCO-2) satellite observations. The first one applies the Gaussian plume model to optimize emissions by fitting modeled CO2 enhancement to the observation. The second and third methods apply the same inversion framework using the maximum likelihood estimation, but with WRF-Chem and WRF-FLEXPART as forward models, respectively. We evaluate consistency between the three methods in estimating emissions of 10 power plants in the US, using daily reported values from the US Environmental Protection Agency (EPA) as a benchmark, and then apply the three methods to quantify emissions of 13 power plants in China. Results show that the WRF-Chem and WRF-FLEXPART based inversion results are consistent with the EPA reported emission rates, with correlation coefficients (r) of 0.76 and 0.85 and mean biases (MB) of 4.06 and 3.97 ktCO2/d relative to EPA reports at all 10 power plants, respectively. The Gaussian plume model driven by wind fields from WRF-Chem model without the wind rotation shows comparable ability in reproducing the EPA reported emission rates at 7 power plants (r = 0.82, MB = 6.17), but is not applicable for the other three cases. We find that application of the high-resolution three-dimensional wind fields can better capture the shape of observed plumes, especially under complex wind conditions, compared to the Gaussian plume model which relies on wind field at a single point, and thus the Gaussian plume model has difficulty to optimize emissions under inhomogeneous wind fields or when observations are far away from the power plant. In general, using the WRF-FLEXPART model as the forward model in the inverse analysis shows advanced capability to simulate narrow-shape plumes in the absence of numerical diffusion which is inherent in Eulerian model such as WRF-Chem. Emissions estimated by the three top-town methods show a moderate consistency at 13 coal-fired power plant cases in China, with 8 of 13 cases showing differences of <30% between at least two methods. However, large differences emerge when wind fields are inhomogeneous and number of available observations is limited. Using different meteorological wind fields and OCO-2 data versions can also bring substantial differences to the posterior emissions for all three approaches. We find that the posterior CO2 emissions, though only reflecting instantaneous emission rates at satellite overpass time, are not proportional to the reported capacities of these power plants, indicating that attributing CO2 emissions simply based on the capacity of power plants in some bottom-up approaches may have significant discrepancies. Our study exposes the capability and limitation of different top-down approaches in quantifying point-source CO2 emissions, advancing their application for better serving increasing constellations of point-source imagers in the future.

Assessment of potential health risks associated with heavy metal concentrations in leafy vegetables in Kerman, Iran

ABSTRACT Despite the growing awareness of the nutritional benefits of leafy vegetables, there is a lack of information about the presence of heavy metals and the associated risks in these products. This study aimed to investigate the concentration of heavy metals in leafy vegetables in Kerman City. The research also assessed the intake of heavy metals and the associated drisks for children and adults who consume these vegetables. The study followed the recommended methods by the US Environmental Protection Agency (USEPA) to evaluate both carcinogenic and non-carcinogenic diseases. A total of 400 leafy vegetable samples, including parsley, coriander, Persian leek, and basil, were randomly collected from agricultural farms in the outskirts of Kerman City. The samples were analysed using a graphite furnace atomic absorption spectrometer to measure the concentrations of lead (Pb), cadmium (Cd), iron (Fe), and copper(Cu). The results revealed that the levels of heavy metals in leafy vegetable samples exceeded the recommended standards set by international organisations such as FAO/WHO, European countries, and Iran. The total target hazard quotient (THQ) for non-carcinogenic diseases resulting from the consumption of leafy vegetables was higher than one for both children and adults in all studied areas, indicating a potential risk of non-carcinogenic diseases associated with the consumption of these vegetables. Furthermore, the average Incremental Lifetime Cancer Risk (ILCR) resulting from exposure to agricultural soil through leafy vegetable consumption exceeded the hazardous and unacceptable range of 104− × 10−6 in both children and adults. This suggests the possibility of carcinogenic diseases caused by Pb and Cd through the consumption of leafy vegetables in all studied areas, with a higher overall risk observed in children compared to adults. In conclusion, while leafy vegetables are widely recognised for their nutritional benefits, our study underscores a critical gap in understanding the presence of heavy metals and the associated risks in these products. The findings reveal that the concentrations of heavy metals in leafy vegetables from Kerman City exceed international standards, posing potential health risks, particularly in children. Further research and regulatory actions are warranted to address this pressing issue and ensure the safety of our food supply.

211 Analysis of microbial communities from a commercial-size swine manure pit and their association with production of volatile organic compounds

Abstract Global pollution and emission concerns have been linked to concentrated animal feeding operations (CAFOs). Indeed, the U.S Environmental Protection Agency (US EPA) warns that there is a significant danger to human health, soil, and water quality from CAFOs. Volatile organic compounds (VOCs), which are amongst air contaminants that pose a serious risk, are abundantly produced in swine manure pits. While VOC emissions from swine manure have been well studied, the microbial species responsible for their production remain mostly uncharacterized. Thus, a deeper comprehension of the microorganisms responsible for VOC production in swine manure pits may help in the development of management approaches that target the microbiome in these environments. In this context, this study aimed to identify the major bacterial species populating the manure pit of a commercial-size swine wean-to-finish research facility. Manure collected from two sampling locations at different time points were analyzed using the 16S rRNA gene through PCR-amplification of the V1-V3 regions from microbial genomic DNA, followed by Illumina MiSeq 2X300 sequencing. An analysis of the most highly represented microorganisms identified 24 bacterial Operational Taxonomic Units (OTUs), with only four showing a species-level nucleotide sequence identity to currently known or valid species. As these results indicated that the majority of bacterial species from this manure pit were unknown, a metagenomics approach was used to assemble partial to full length genomes from the two most abundant OTUs: Pit_9-00239 [5.09% - 19.44%; Clostridium saccharoperbutylacetonicum (96.60%)] and Pit_ 7-00035 [5.58% - 17.30%; Bacteroides eggerthii (87.66%)]. From genome assembly analysis, 979 contigs were generated for a combined length of 12,367,510 bp, which together included 21,776 coding sequences. Predicted metabolic functions from these contig sets included pathways involved in carbohydrate utilization (glycolysis), vitamin synthesis (riboflavin), and butyrate production (volatile fatty acids). Notably, an enzyme responsible for the production of indole, a common VOC produced from swine manure pits, was also identified. Together, the results from this analysis provide insights on metabolic capabilities of abundant bacterial species from manure pits. These can in turn be used for the future development of management strategies or products that can reduce VOC emissions that result from swine CAFO manure storage.

110 Effects of increasing levels of soybean meal in nursery diets on growth performance and fecal dry matter of 10 to 25 kg pigs

Abstract With the recent Renewable Fuel Standard Program developed by the Environmental Protection Agency, soybean oil is expected to be in record demand by the fuel energy industry. As a result, there will be the potential opportunity for increased usage of soybean meal (SBM) in swine diets. Therefore, the objective of this study was to evaluate the effect of different levels of SBM in late nursery diets on growth performance and fecal dry matter (DM). In Exp. pigs [n = 1,266; DNA 241 × 600; initial body weight (BW) = 10.1 ± 0.27 kg] were fed 1 of 4 dietary treatments which were corn-based with SBM levels of 25.0, 28.9, 32.5, or 36.2%. In Exp. pigs (n = 2,340; DNA 241 × 600; initial BW = 13.5 ± 0.29 kg) were fed 1 of 5 dietary treatments which were corn-based with SBM levels of 25.0, 28.9, 32.5, 36.2, or 40.0%. Both experiments lasted 21 d with 14 replicate pens/treatment and 4 or 5 pigs/pen. At d 21 and 26 postweaning for Exp. 1 and 2, respectively, pens of pigs were randomly allotted to treatments in a randomized complete block design with BW as the blocking factor. Additions of SBM replaced feed-grade amino acids to form experimental diets, and all diets were formulated to be nearly isocaloric with SBM NE considered to be 100% of corn NE. Dietary additions of feed-grade AA were adjusted to meet or exceed NRC (2012) AA requirements in relation to Lys for Ile, Met, Cys, Thr, Trp, and Val. In Exp. 1, increasing SBM from 25.0 to 36.2% decreased average daily gain (ADG; linear, P = 0.012), average daily feed intake (ADFI; linear, P &amp;lt; 0.001), and final BW (linear, P = 0.021), with the greatest change occurring when SBM increased from 28.9 to 32.5% (Table). No evidence for difference between treatments was observed for gain to feed ratio (G:F; P = 0.729). Fecal DM decreased (linear, P &amp;lt; 0.006) as SBM increased in the diet at d 7, but not on d 21. In Exp. 2, starting with a heavier initial BW, increasing SBM from 25.0 to 40.0% decreased ADFI (linear, P = 0.017), with the greatest change occurring when SBM increased from 32.5 to 36.2%. However, no evidence for treatment differences (P ≥ 0.198) was observed for ADG, final BW, or G:F. Fecal DM decreased (linear, P ≤ 0.046) at d 7 and 21 as SBM increased in the diet. In conclusion, feeding greater than 28.9% SBM for nursery pigs starting at 10 kg BW does compromise performance, but when pigs are closer to 13.5 kg BW, greater SBM diets did not affect ADG or G:F. Also, increasing the level of SBM reduced fecal DM more markedly a week after the transition to high SBM diets compared with 3 wk after the start of treatment feeding.

Year-round monitoring of three water sources in Québec, Canada, reveals site-specific differences in conditions for Cryptosporidium and Giardia contamination.

Cryptosporidium and Giardia are protozoan parasites responsible for gastrointestinal illnesses in humans and in animal species. The main way these parasites are transmitted is by ingestion of their (oo)cysts in drinking water. Monitoring (oo)cysts in water sources is beneficial to evaluate the quality of raw water supplying treatment plants. Currently, the only standardized protocol to enumerate these parasites from water samples is United States Environmental Protection Agency (USEPA) Method 1623.1. With this method, we monitored three major water sources in Quebec over a year to assess temporal and geographical variations of these parasite (oo)cysts. These three water sources have independent watersheds despite being in the same region. We found a general pattern for Giardia, with high concentrations of cysts during cold and transition periods, and significantly lower concentrations during the warm period. Cryptosporidium's concentration was more variable throughout the year. Statistical correlations (Pearson's correlation coefficients) were established between the concentration of each parasite and various environmental parameters. The three study sites each showed unique factors correlating with the presence of both protozoa, supporting the idea that each water source must be seen as a unique entity with its own particular characteristics and therefore, must be monitored independently. Although some environmental parameters could be interesting proxies to the parasitic load, no parameter was strongly correlated throughout the whole sampling year and none of the parameters could be used as a single proxy for all three studies sources.

Nitrogen dioxide exposure, health outcomes, and associated demographic disparities due to gas and propane combustion by U.S. stoves.

Gas and propane stoves emit nitrogen dioxide (NO2) pollution indoors, but the exposures of different U.S. demographic groups are unknown. We estimate NO2 exposure and health consequences using emissions and concentration measurements from >100 homes, a room-specific indoor air quality model, epidemiological risk parameters, and statistical sampling of housing characteristics and occupant behavior. Gas and propane stoves increase long-term NO2 exposure 4.0 parts per billion volume on average across the United States, 75% of the World Health Organization's exposure guideline. This increased exposure likely causes ~50,000 cases of current pediatric asthma from long-term NO2 exposure alone. Short-term NO2 exposure from typical gas stove use frequently exceeds both World Health Organization and U.S. Environmental Protection Agency benchmarks. People living in residences <800 ft2 in size incur four times more long-term NO2 exposure than people in residences >3000 ft2 in size; American Indian/Alaska Native and Black and Hispanic/Latino households incur 60 and 20% more NO2 exposure, respectively, than the national average.

Effects of chemical composition of ambient PM2.5 measured in Seoul on potential health risks and generation of reactive oxygen species

This study assesses the health effects associated with the chemical species of ambient particulate matter (PM) with an aerodynamic diameter ≤ 2.5 μm (PM2.5) in Seoul, focusing on identifying key chemical constituents and their sources. We employed two approaches to estimate health risks: (1) evaluating carcinogenic and noncarcinogenic risks using IRIS (Integrated Risk Information System) data from the US EPA (Environmental Protection Agency), and (2) quantifying the generation of hydroxyl radicals (·OH) following exposure to PM2.5 in surrogate lung fluid (SLF). Our results show a significant impact on human health from certain elements (Cr, Ni, As, and Cd) and polycyclic aromatic hydrocarbons (PAHs) (DaeP, DahA, and BaP for carcinogenic risks; BaP and BeP for noncarcinogenic risks). Notably, Cr and BaP, which are influential in both risk assessment and ·OH generation, highlight their significant roles in human health impacts. However, other components (e.g., CPP, BaP, BghiP, BaA, CHR, PYR, FLT, Ca, Mg, and Cu), though contributors to ·OH generation, were not included in the EPA’s health risk assessment, suggesting a need for a broader PM2.5 compositional analysis to more accurately determine exposure concentrations and assess inhalation risks. These components predominantly originate from anthropogenic sources, such as combustion, vehicles, and industrial activities, underscoring the significant health implications of the pollutants emitted from these sources. The study concluded that focusing solely on the mass reduction of PM2.5 may not suffice; a dual approach that reduces both mass concentration and chemical-specific health risks is imperative for effective public health protection.

Disproportionate Clean Air Act violations occur in communities of color throughout the United States

The United States (U.S.) Clean Air Act seeks to prevent and abate ambient air pollution, while also providing a framework to identify and address violations. Little research has examined where or how frequently violations of the Clean Air Act occur and how marginalized communities may bear a disproportionate share of these violations, despite the fact that marginalized communities experience persistent, disproportionate pollution levels and associated health impacts. Here, we leverage data on Clean Air Act enforcement and compliance together with demographic data to show that the most serious violations of the Act—high priority violations (HPVs)—predominantly occur in communities of color throughout the U.S. Specifically, we find that the number of facilities with an HPV within communities with the largest proportion of people of color is nearly two times greater than in communities with the smallest proportion. Only 6% of facilities with an HPV address their violations within the timeframe mandated by the U.S. Environmental Protection Agency, and a larger share of facilities with an HPV in disadvantaged communities do not address their violations within this timeframe compared to facilities with an HPV in non-disadvantaged communities. Enforcing agencies should improve how violations are communicated and addressed. To this end, we suggest several ways to empower individuals and communities with easy-to-access data related to Clean Air Act violations and that enforcement practices and reporting be standardized across enforcing agencies.

Unregulated drinking water contaminants and adverse birth outcomes in Virginia

Unregulated drinking water contaminants and adverse birth outcomes in Virginia

Do we have enough room for the trees we need?

In 2021, two guidelines were introduced with the purpose of increasing cities’ tree canopy coverage (TCC): Konijnendijk’s 3-30-300 rule, where 30 represents the goal to achieve at least 30% TCC, and the Swedish Environmental Protection Agency’s (SEPA) guideline, aiming for all Swedish cities to increase their TCC by two percentage points (%pts) within a period of 10 years. While these ambitious goals are positive, not least from a sustainability perspective, there is a lack of research on whether these goals are feasible and how to reach them in practice. The overall TCC in Uppsala, Sweden’s fourth largest city, is 28%, with considerably lower TCC in the eastern parts of the city. In this study, we will investigate, and visualise, how a 2%pts increase as well as 30% TCC could be achieved in two areas in eastern Uppsala: Fålhagen, a residential area, and Boländerna, a commercial and industrial area. We used geographical information systems (GIS) and a scenario approach to calculate the number of trees needed, and possible locations for them, to achieve a 2-%pts-increase or the 30% TCC goal. The results show that an increase of 2%pts seems possible in both areas, particularly if the municipality and private property owners collaborate. However, it is difficult to estimate the time needed until the canopies of the proposed trees have become large enough to reach the 2%pts increase. It does not seem likely to reach 30% TCC in eastern Uppsala with today’s land use. To be able to reach the goals presented in this paper, it seems necessary to include them in municipality policies. Perhaps Konijnendijk’s and SEPA’s guidelines can be starting points for such policies and applied as rules-of-thumb rather than applicable planning tools.