Mixture Of Pollutants Research Articles

Domestic groundwater wells in Appalachia show evidence of low-dose, complex mixtures of legacy pollutants.

Lack of water quality data for private drinking water sources prevents robust evaluation of exposure risk for communities co-located with historically contaminated sites and ongoing industrial activity. Areas of the Appalachian region of the United States (i.e., Pennsylvania, Ohio and West Virginia) contain extensive hydraulic fracturing activity, as well as other extractive and industrial technologies, in close proximity to communities reliant on private drinking water sources, creating concern over potential groundwater contamination. In this study, we characterized volatile organic compound (VOC) occurrence at 307 private groundwater well sites within Pennsylvania, Ohio, and West Virginia. The majority (97%) of water samples contained at least one VOC, while the average number of VOCs detected at a given site was 5 ± 3. The majority of individual VOC concentrations fell below applicable U.S. Environmental Protection Agency (EPA) Maximum Contamination Levels (MCLs), except for chloroform (MCL of 80 μg L-1; n = 1 at 98 μg L-1), 1,2-dibromoethane (MCL of 0.05 μg L-1; n = 3 ranging from 0.05 to 0.35 μg L-1), and 1,2-dibromo-3-chloropropane (MCL of 0.2 μg L-1; n = 7 ranging from 0.20 to 0.58 μg L-1). To evaluate well susceptibility to VOCs from industrial activity, distance to hydraulic fracturing site was used to assess correlations with contaminant occurrences. Proximity to closest hydraulic fracturing well-site revealed no statistically significant linear relationships with either individual VOC concentrations, or frequency of VOC detections. Evaluation of other known industrial contamination sites (e.g., US EPA Superfund sites) revealed elevated levels of three VOCs (chloroform, toluene, benzene) in groundwaters within 10 km of those Superfund sites in West Virginia and Ohio, illuminating possible point source influence. Lack of correlation between VOC concentrations and proximity to specific point sources indicates complex geochemical processes governing trace VOC contamination of private drinking water sources. While individual concentrations of VOCs fell well below recommended human health levels, the low dose exposure to multiple VOCs occurring in drinking supplies for Appalachian communities was noted, highlighting the importance of groundwater well monitoring.

Combined short-term exposure to meteorological, pollution factors and pertussis in different groups from Jining, China.

Previous studies have typically explored daily lagged relationships among pertussis and meteorology, with little assessment of effect and interaction among pollutants mixtures. Our researchers collected pertussis cases data from 2017-2022 as well as meteorological and contaminative factors for the Jining region. First, we reported the application of the Moving Epidemic Method (MEM) to estimate epidemic threshold and intensity level. Then we developed a Weighted Quantile Sum (WQS) regression and Bayesian Kernel Machine Regression (BKMR) model to assess single, multiple effects and interaction of meteorological and pollution factors on pertussis cases for different sex, delayed and epidemic threshold groups. There has been a yearly upward trend in the incidence of pertussis in Jining regions. High prevalence threshold years were in 2018-2019, the epidemic peak was mainly concentrated in 32 weeks. Totally, pertussis infections disease was separately 2.1% (95% confidence Interval (CI) = 1.3, 2.8) and 1.1% (95% CI = 0.3, 1.9) higher per decile increase in temperature and sulphur dioxide (SO2). And pertussis infections disease was 1.1% lower per decile increase in humidity. In the different stratified analyses, air pressure was a strong negative effect in males and in the lagged 11-20 days group, with 7.3 and 14.7%, respectively. Sulphur dioxide had a relatively weak positive effect in males, females and the group after 20 days lag, ranging from 0.5 to 0.6%. The main positive effectors affecting the onset of disease at low and high threshold levels were ozone (O3) and SO2, respectively, while the negative effectors were SO2 and carbon monoxide (CO), respectively. This is the first mathematically based study of seasonal threshold of pertussis in China, which allows accurate estimation of epidemic level. Our findings support that short-term exposure to pollutants is the risk factor for pertussis. We should concentrate on pollutants monitoring and effect modeling.

Perfluorooctane sulfonate (PFOS) and benzo[a]pyrene (BaP) synergistically induce neurotoxicity in C6 rat glioma cells via the activation of neurotransmitter and Cyp1a1-mediated steroid hormone synthesis pathways

Humans are often exposed to complex mixtures of multiple pollutants rather than a single pollutant. However, the combined toxic effects and the molecular mechanism of PFOS and BaP remain poorly understood. In this study, two typical environmental pollutants, perfluorooctane sulfonate acid (PFOS) and benzo[a]pyrene (BaP), were selected to investigate their combined neurotoxic effects on rat C6 glioma cells at environmentally relevant concentrations. The results showed that coexposure to low-dose PFOS and BaP induced greater toxicity (synergistic effect) than did single exposure. PFOS-BaP coexposure had stronger toxic effects on inducing oxidative stress and promoting early apoptosis. Targeted metabolomics confirmed that increased levels of the neurotransmitters 5-hydroxytryptophan, dopamine, tryptophan and serotonin disturb the phenylalanine, tyrosine and tryptophan biosynthesis pathways. Mechanistically, exposure to a low-dose PFOS-BaP binary mixture induces steroid hormone synthesis disorder through the activation of Cyp1a1 and Hsd17b8 (steroid hormone synthesis genes) and Dhcr24 and Dhcr7 (cholesterol synthesis genes). These findings are useful for comprehensively and systematically elucidating the biological safety of PFOS-BaP and its potential threats to human health.

Combined health effects of air pollutant mixtures on respiratory mortality using BKMR in Hangzhou, China

ABSTRACT Previous research on respiratory system mortality primarily focused on understanding their combined effects and have neglected the fact that air pollution mixtures are interrelated. This study used Bayesian kernel machine regression (BKMR) to analyze the relationship between air pollutant mixtures and respiratory mortality in Hangzhou, China from 2014 to 2018. The results showed a significant association between pollutant mixtures and respiratory system mortality primarily driven by PM2.5 and SO2. The joint exposure of air pollutants was positively correlated with respiratory system mortality at lag 01 and lag 02 days. The estimated joint effects of log-transformed mixture air pollution exposure on log-transformed respiratory system mortality increased from −0.02 (95% CI: −0.08–0.02) and −0.01 (95% CI: −0.05–0.04) at the 25th percentile to 0.06 (95% CI: 0.01–0.12) and 0.04 (95% CI: −0.001, 0.09) at the 75th percentile. Additionally, there was evidence of an interaction between O3 and PM10. This study confirms that exposure to multiple pollutants is a significant public health problem facing the Hangzhou population given the compounded effect proven with regression analysis, while furthermore, the control of PM2.5 and SO2 also represents a serious concern. Implications: Evidence indicates interactions between O3 and PM10. This study demonstrates that exposure to multiple pollutants exerts combined effects on the public health of the Hangzhou population, highlighting the importance of controlling PM2.5 and SO2.

Enhancing leachate management with antibacterial nanocomposites incorporating plant-based carbon dots and Satureja Khuzestanica essential oils

Landfill leachate, a complex mixture of pollutants, poses a significant environmental hazard. This study reports the synthesis and characterization of superabsorbent nanocomposites (SANs) designed for enhanced performance in waste management applications. SANs were prepared using carboxymethyl cellulose (CMC) and sodium polyacrylate (SPA) as the main components, carbon dots (CDs) to improve absorption, and Satureja Khuzestanica essential oil (SEO) for antibacterial performance. The results demonstrated that the addition of CDs significantly increased the absorption capacity and liquid retention of the samples, with a water absorption capacity reaching up to 8621 %. Furthermore, the samples exhibited high mechanical strength, with tensile strength improving by over 100 % in the presence of CDs. The inclusion of SEO provided strong antibacterial activity against Escherichia coli and Staphylococcus aureus, with inhibition zones measuring up to 26 mm. These SANs, with their high absorption capacity, mechanical robustness, and antibacterial properties, show great potential for improving waste management practices, particularly in leachate absorption strategies.

Impact of biomass burning on air quality: A case study of the agricultural region in South Korea

Various combustion processes occur concurrently during biomass burning events, emitting a complex mixture of particulate and gaseous pollutants into the atmosphere. These emissions undergo chemical transformations facilitated by factors such as solar radiation and cloud formation, thereby altering the composition of aerosols. Additionally, these pollutants can affect the region of origin and neighboring countries, presenting regional and global environmental challenges. Therefore, precise evaluation of the particulate and gaseous pollutants emitted during biomass burning is essential to formulate effective management strategies. This study aimed to assess the concentration and chemical characteristics of particulate matter emitted during biomass burning in South Korea. On June 7, 2021, a research flight was conducted utilizing a High Resolution Time-of-Flight Aerosol Mass Spectrometer (HR-ToF-AMS) and a Single Particle Soot Photometer (SP2) for airborne measurements over South Korea inland areas. For data analysis based on administrative regions, the flight path was divided into four major areas (Areas A, B, C, and D). During the research flight, evidence of biomass burning events was observed primarily in Area C. A positive matrix factorization (PMF) analysis categorized the organic aerosols (OA) into five factors: biomass burning OA (BBOA), hydrocarbon-like OA (HOA1, HOA2), low-oxidized oxygenated OA (LO-OOA), and more-oxidized OOA (MO-OOA). Across all areas, MO-OOA accounted for the highest proportion of aerosols, whereas BBOA dominated in Area C at 23.8%, indicating the significant influence of biomass burning in this region. Instead of running a PMF analysis with all measurement data, a BBOA formula was derived from the previous study and this one. This allows us to estimate BBOA concentration without running PMF.

Per- and poly-fluoroalkyl substances (PFAS) do not accumulate with age or affect population survival in ruddy turnstone (Arenaria interpres)

Per- and poly-fluoroalkyl substances (PFAS) may threaten wildlife due to their high environmental persistence, toxicity potential and potential to bioaccumulate. Bioaccumulation may be particularly profound in long-lived animals inhabiting higher trophic niches. To date, there is a paucity of data on PFAS bioaccumulation potential in individual wild birds over their lifetime. In this study, we analysed within-individual PFAS contamination in a declining long-distance migratory shorebird, the ruddy turnstone (Arenaria interpres), and the variation in PFAS contamination with age by repeatedly sampling 19 individuals throughout their lives between 2007 and 2022. We found blood-sampled turnstones on their non-breeding grounds in King Island, Tasmania, exhibited no variation of PFAS contamination with age, with low overall circulating PFAS concentrations (<0.015–25 ng/g, median: 0.78 ng/g). Moreover, irrespective of the increased PFAS usage along the East Asian Australasian Flyway over the past two decades, ruddy turnstone survival remained consistent throughout the 15-year sampling period, with no temporal trend in percentage of juveniles in the population. From a conservation perspective, low concentrations of PFAS found in this study are good news as they suggest PFAS alone do not seem to threaten turnstone survival. However, the unknown effects of exposure to mixtures of pollutants may yet threaten turnstones.

Ambient Air Pollutant Mixture, Sleep Pattern, and Incident CKD: Results from a Prospective Cohort Study

Ambient Air Pollutant Mixture, Sleep Pattern, and Incident CKD: Results from a Prospective Cohort Study

Single- and two-pollutant Concentration-Response Functions for PM2.5 and NO2 for Quantifying Mortality Burden in Health Impact Assessments

ObjectiveHealth Impact Assessments (HIAs) for air pollutant mixtures are challenging because risk estimates are primarily derived from single-pollutant models. Combining risk estimates from multiple pollutants requires new approaches, as a simple addition of single pollutant risk estimates from correlated air pollutants may result in double counting. We investigated approaches applying concentration-response functions (CRFs) from single- and two-pollutant models in HIAs, focusing on long-term exposure to particulate matter with a diameter less than 2.5 micrometers (PM2.5) and nitrogen dioxide (NO2) and their associations with all-cause mortality. MethodsA systematic literature search of MEDLINE and EMBASE identified cohort studies employing single- and two-pollutant models of long-term exposure to PM2.5 and NO2 with all-cause mortality. Pooled CRFs were calculated through random-effects meta-analyses of risk estimates from single- and two-pollutant models. Coefficient differences were calculated by comparing single- and two-pollutant model estimates. Four approaches to estimating population-attributable fractions (PAFs) were compared: PM2.5 or NO2 single-pollutant models to represent the mixture, the sum of single-pollutant models, the sum of two-pollutant models and the sum of single-pollutant models from a larger body of evidence adjusted by coefficient difference. ResultsSeventeen papers reported both single and two-pollutant estimates. Pooled hazard ratios (HRs) for mortality from single- and two-pollutant models were 1.053 (95% confidence interval: 1.034-1.071) and 1.035 (1.014-1.057), respectively, for a 5 μg/m3 increase in PM2.5. HRs for a 10 μg/m3 increase in NO2 were 1.032 (1.014-1.049) and 1.024 (1.000-1.049) for single- and two-pollutant models, respectively. The average coefficient difference between single- and two-pollutant models was 0.017 for PM2.5 and 0.007 for NO2. Combined PAFs for the PM2.5-NO2 mixture using joint HRs from single- and two-pollutant model CRFs were 0.09 and 0.06, respectively. ConclusionUtilizing CRFs from two-pollutant models or applying the coefficient difference to a more extensive evidence base seems to mitigate the potential overestimation of mixture health impacts from adding single-pollutant CRFs.

Enhanced Visible-Light-Assisted Photocatalytic Removal of Tetracycline Using Co/La@g-C3N4 Ternary Nanocomposite and Underlying Reaction Mechanisms

Graphitic carbon nitride (g-C3N4) is a promising material for photocatalytic applications. However, it suffers from poor visible-light absorption and a high recombination rate of photogenerated electron–hole pairs. Here, Co/La@g-C3N4 with enhanced photocatalytic activity was prepared by co-doping Co and La into g-C3N4 via a facile one-pot synthesis. Co/La@g-C3N4 displayed better performance, achieving 94% tetracycline (TC) removal within 40 min, as compared with g-C3N4 (BCN, 65%). It also demonstrated promising performance in degrading other pollutants, which was ~2–4-fold greater relative to BCN. The improved photocatalytic activity of Co/La@g-C3N4 was associated with improved photogenerated charge separation, reduced charge transfer resistance, a built-in electric field arising from the p-n-p heterojunction, and the synergistic effect of ternary components for the separation and transfer of the photogenerated charge carriers. Superoxide radicals are suggested to be the most notable reactive species responsible for the photocatalytic reaction. Environmental factors, including the pollutant concentration, catalyst dosage, solution pH, inorganic salts, water matrices, and mixture with dyes, were considered in the photocatalytic reactions. Co/La@g-C3N4 showed good reusability for five cycles of the photocatalytic degradation of TC. The facile one-pot co-doping of Co and La in g-C3N4 formed a p-n-p heterojunction with boosted photocatalytic activity for the highly efficient removal of TC from various water matrices.

Magnetic Hydrogel Microbots for Efficient Pollutant Decontamination and Self-Catalyzed Regeneration in Continuous Flow Systems.

The efficient removal of organic pollutants from water is crucial for protecting human health and the ecosystem. While adsorbent-based approaches offer advantages over traditional chemical and thermal methods, they still suffer from slow adsorption kinetics, high energy demand, and limited material lifespan. Herein, an efficient decontamination platform is introduced, using magnetic hydrogel microbots (MHMs) made from picolitre-sized hydrogel droplets coated with multifunctional magnetic nanoparticles. This approach includes 1) dividing a droplet into smaller microbots to enhance their interaction with sample solution and 2) dynamically spinning these MHMs to generate hydrodynamic flows that actively draw pollutants toward the embedded hydrogel for capture. The MHMs show high decontamination effectiveness in both bulk and continuous flow setups, achieving ≈95% removal efficiency within 3min. Further integrating MHMs with a non-pressurized fluidic platform enables energy-efficient continuous flow decontamination, removing ≥95% total organic carbon from a complex pollutant mixture at a flow rate surpassing other recent designs. Additionally, the MHMs facilitate self-catalyzed regeneration using an environmentally friendly H2O2 precursor, allowing for long-term and repeated usage. By enabling the unique divide-and-arrest decontamination of toxic pollutants, the multifunctional design holds tremendous promise for on-site wastewater treatment to ensure safe water access for everyone, even in resource-limited environments.

Association between City-Level Particulate Matter Exposure and Frailty among Middle-Aged and Older Adults in China

Introduction: The effects of exposure to particulate matter and frailty, as well as its exposure-response relationship, have not been effectively explored. This study aimed to explore the association between long-term exposure to particulate matter and frailty state and each dimension in Chinese middle-aged and older adults, in addition to the exposure-response relationship. Methods: The data were obtained from the National Urban Air Quality Real-Time Dissemination Platform and China Health and Retirement Longitudinal Study (CHARLS). Frailty was measured by a frailty index containing 39 indicators. Annual averages of seven pollutants were calculated from hourly monitoring data. We used multilevel regression modeling to explore the association between long-term exposure to particulate matter and frailty. Meanwhile, we explored the exposure-response relationship based on a multilevel generalized summation model. We performed a sensitivity analysis using a multi-pollution model and a quantile-based g-computation (QGC) model. Results: A total of 15,611 participants were included in the analysis. We find that long-term exposure to PM2.5 was associated with an increased risk of pre-frailty and frailty (all p < 0.05). PMc and PM10 exhibited similar associations. The exposure-response relationship between PM2.5 showed a linear relationship, whereas the exposure-response relationship between PM10, PMc showed a nonlinear relationship. Elevated PM2.5 concentrations showed significant positive associations with the number of chronic disease score, IADL score, and functional limitation status score (all p < 0.05). PM10 and PMc showed similar positive correlations. These results remained robust after sensitivity analyses using a multi-pollution model and QGC model. Conclusion: Chronic exposure to particulate matter was significantly associated with increased risk of frailty. The exposure-response relationship between PM2.5 concentration and frailty showed a linear relationship, and the exposure-response relationship between PM10 and PMc showed a nonlinear relationship. Exposure to a mixture of pollutants carried a higher risk of frailty than exposure to a single pollutant.

The Role of Mass Spectrometry in Protecting Public Health and the Environment from Synthetic Chemicals.

Mass spectrometry (MS) has dramatically transformed environmental protection by facilitating the precise quantification and identification of pollutants. This review charts the evolution of environmental chemistry, intertwining it with advancements in analytical chemistry and MS technologies. It specifically focuses on the role of MS in studying persistent organic pollutants like organochlorine pesticides, polychlorinated biphenyls (PCBs), brominated fire retardants (BFRs), and perfluoroalkyl and polyfluoroalkyl substances (PFAS), marking significant milestones and their implications. Notably, the adoption of gas chromatography with MS in the 1970s and liquid chromatography with MS in the late 1990s profoundly expanded scientists' ability to detect complex pollutant mixtures. Over the past 50 years, the proliferation of potential pollutants has surged, necessitating more sophisticated analysis techniques, such as high-resolution mass spectrometry-nontargeted analysis (HRMS-NTA) and suspect screening. While HRMS promises to enhance the characterization of new environmental pollutants, a significant shift in chemical management strategies remains imperative. Despite technological advances, MS alone is insufficient to mitigate the risks from the continuous emergence of novel chemicals, with many potentially already present in the environment and bioaccumulating in humans.

P01-12 Rapid assessment of pulmonary genotoxicity induced by pollutant mixtures in vitro at the air-liquid interface using a semi-automated methodology

P01-12 Rapid assessment of pulmonary genotoxicity induced by pollutant mixtures in vitro at the air-liquid interface using a semi-automated methodology

P21-08 Health based quality criteria for a mixture of environmental pollutants on the beaches and in sea water

P21-08 Health based quality criteria for a mixture of environmental pollutants on the beaches and in sea water

Assessment of the Respiratory Disease Mortality Risk from Single and Composite Exposures to PM2.5 and Ozone - Guangzhou City, Guangdong Province, China, 2018-2021.

Fine particulate matter (PM2.5) and ozone (O3) are prevalent pollutants in the atmosphere, which threaten human health, especially the respiratory system. Typically, people are exposed to a mixture of various pollutants in the environment. Thus, the single and combined effects of both pollutants need to be investigated. PM2.5 and O3 increase the risk of death from lung cancer, chronic obstructive pulmonary disease (COPD), and respiratory diseases, with their lagged and cumulative effects analyzed, indicating an acute effect. In addition, combined exposure to both pollutants can significantly affect disease deaths. This study provides further evidence of the single and combined effects of PM2.5 and O3 on respiratory diseases, emphasizing the need for sustained efforts in air pollution control, with greater attention to the synergistic management of air pollutants.

Grouped mixtures of air pollutants and seasonal temperature anomalies and cardiovascular hospitalizations among U.S. residents

Grouped mixtures of air pollutants and seasonal temperature anomalies and cardiovascular hospitalizations among U.S. residents

Association between long-term exposure to mixture of ambient air pollutants and bladder cancer incidence

Association between long-term exposure to mixture of ambient air pollutants and bladder cancer incidence

Prenatal Ambient Air Pollutant and Climatic Factors Mixture Exposure and Fetal Growth

Prenatal Ambient Air Pollutant and Climatic Factors Mixture Exposure and Fetal Growth

Air pollution mixture associated with oxidative stress exacerbation and symptoms deterioration in allergic rhinitis patients: evidence from a panel study

Air pollution mixture associated with oxidative stress exacerbation and symptoms deterioration in allergic rhinitis patients: evidence from a panel study