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1.
Environ Int ; 158: 106986, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34991248

RESUMEN

BACKGROUND/AIMS: Early life exposures to marine contaminants can adversely impact child health but modes of action are unclear. Human milk contains extracellular vesicles (EVs) that can transport biologically relevant cargo from mother to infant, including microRNAs (miRNAs), and may partly mediate the effects of pollutants on child health. However, the role of marine pollutants on miRNA expression in milk EVs is unexplored. METHODS: We isolated EV RNA from 333 milk samples collected between 2 and 74 days postpartum from a Faroese birth cohort born 1997-2000 and sequenced 2083 miRNAs using a targeted library preparation method. We quantified five perfluoroalkyl substances (PFAS), pesticide metabolite p,p'-dichlorodiphenyldichloroethylene (DDE), and the sum of three major polychlorinated biphenyls (ΣPCBs) in maternal serum at 34 weeks of gestation and maternal hair total mercury (Hg) at birth. We used negative binomial regressions to estimate associations between individual pollutants and 418 reliably expressed EV-miRNAs adjusted for potential confounders. We performed sparse principal components (PCs) analysis to derive the first four components of the EV-miRNA data and examined associations between pollutants and PCs using Bayesian kernel machine regression (BKMR). RESULTS: We observed no associations between pollutants and individual EV-miRNA expression after controlling the false discovery rate at 0.1. However, BKMR suggested that Hg was positively associated with PC1 and negatively associated with PC3, while ΣPCBs was negatively associated with PC3, and two PFAS were associated with PC4. Exploration of PC loadings followed by pathway analyses suggested that miRNAs in PC1 (miR-200b-3p, miR-664a-3p, miR-6738-5p, miR-429, miR-1236-5p, miR-4464, and miR-30b-5p) may be related to Hg neurotoxicity, while remaining PCs require further research. CONCLUSIONS: Our findings suggest that groups of milk EV-miRNAs may better serve as environmental biomarkers than individual miRNAs. Future studies are needed to elucidate the role of milk EV-miRNAs in child health following prenatal exposures.


Asunto(s)
Contaminantes Ambientales , Vesículas Extracelulares , MicroARNs , Teorema de Bayes , Niño , Contaminantes Ambientales/toxicidad , Femenino , Humanos , Recién Nacido , MicroARNs/genética , Leche Humana , Madres , Embarazo
2.
Huan Jing Ke Xue ; 43(1): 277-284, 2022 Jan 08.
Artículo en Chino | MEDLINE | ID: mdl-34989512

RESUMEN

In this study, we separately collected rainwater sewer sediments from typical samples in Suzhou city, such as the urban commercial district, historical and cultural protection area, cultural and educational area, and living area, and analyzed the particle size distribution of the sediments and the characteristics of carbon, nitrogen, phosphorus content, and pollution load distribution under each graded particle size. The median particle size D50 of each sample point was 16.55-327.50 µm, and the particle size trend was as follows:commercial area > living area > historical and cultural protection area > cultural and educational area. D50 was related to the total organic carbon (TOC). The total nitrogen (TN), total phosphorus (TP), and ammonia nitrogen (NH4+-N) were significantly positively correlated, as were the pollutants. The spatial difference of ω(TOC), ω(TN), ω(TP), and ω(NH4+-N) in rainwater sewer sediments from different regions was as follows:commercial area > historical and cultural protection area > living area > cultural and educational area, in which ω(TOC) was 0.84%-6.76%, and ω(TN), ω(TP), and ω(NH4+-N) were 917.5-12707.1, 196.1-2524.8, and 9.3-156.8 mg·kg-1, respectively. TOC, TP, and NH4+-N pollution loads were mainly concentrated on particles ≤ 75 µm and 250-1000 µm. Street dust pollutants highly differed spatially, with a high content of attached pollutants on street dust particles with a particle size of ≤ 75 µm. Various pollutants migrated into the street dust-pipes, and TP and TN showed certain enrichment characteristics in the sewer. Controlling the transportation of street dust and the accumulation of sediments in the sewer can reduce the pollution of sediment into the rivers during the rainy season.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , China , Monitoreo del Ambiente , Sedimentos Geológicos , Nitrógeno/análisis , Fósforo/análisis , Contaminantes Químicos del Agua/análisis
3.
J Environ Manage ; 302(Pt B): 114080, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34773781

RESUMEN

The present study investigates the environmental benefits of phasing-in autonomous ships in global maritime transportation along major dry bulk and tanker routes using Bayesian probabilistic forecasting algorithm. The focus is on the simulations and calibrations on the navigational behavior of autonomous ships at both port and high-sea, as well as the potential emission abatement of atmospheric pollutants compared to the conventional fleet along the sailing routes. We use historical data on major international tanker and dry bulk trade routes to characterize the ship movements and trends in ship emission. Different scenarios are evaluated with a combination of autonomous ship phase-in rates (25, 75, 100%) and cleaner fuel choices in Years 2030 and 2050 (from the baseline Year, 2020). The results show that the magnitude of the emission reduction generally increases with a higher level of autonomous ships in the fleet as expected, and the magnitude ranges from small increments to major reductions of 37-64% along the different routes. Overall, we hope that our findings can contribute towards the realization of environmental benefits with the adoption of autonomous shipping along the major shipping routes in the future.


Asunto(s)
Contaminantes Atmosféricos , Contaminantes Ambientales , Contaminantes Atmosféricos/análisis , Teorema de Bayes , Navíos , Transportes , Emisiones de Vehículos/análisis
4.
Bioresour Technol ; 344(Pt B): 126268, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34737052

RESUMEN

A high-performance biochar derived from the residue of Chaga mushroom (Inonotus obliquus) was reported in this study. Inonotus obliquus residues were used to prepare biochar, and the optimal synthesis conditions were obtained by response surface methodology. The specific surface area, pore volume, and average pore size of the optimal biochar (Zn-IORBC) was 1676.78 m2/g, 1.87 cm3/g, and 3.88 nm, respectively. Methylene blue (MB) and tetracycline (TC) were selected to estimate the adsorption performance of Zn-IORBC. The adsorption process was suitable for the pseudo-second-order model and Langmuir model. Zn-IORBC could maintained a large amount of TC adsorption (the lowest value was 686.20 mg/g in mountain spring water) in different natural water. The maximum adsorption capacity of TC and MB was 947.42 and 1033.66 mg/g. The adsorption mechanism was contributed to the electrostatic attraction, hydrogen bonding, π-π interactions, and pore-filling. Zn-IORBC is an effective adsorbent for high-performance pollutants removal.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Adsorción , Carbón Orgánico , Inonotus , Cinética , Contaminantes Químicos del Agua/análisis
5.
Bioresour Technol ; 344(Pt B): 126245, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34743994

RESUMEN

The bioremediation of emerging pollutants in wastewater via algal biotechnology has been emerging as a cost-effective and low-energy input technological solution. However, the algal bioremediation technology is still not fully developed at a commercial level. The development of different technologies and new strategies to cater specific needs have been studied. The existence of multiple emerging pollutants and the selection of microalgal species is a major concern. The rate of algal bioremediation is influenced by various factors, including accidental contaminations and operational conditions in the pilot-scale studies. Algal-bioremediation can be combined with existing treatment technologies for efficient removal of emerging pollutants from wastewater. This review mainly focuses on algal-bioremediation systems for wastewater treatment and pollutant removal, the impact of emerging pollutants in the environment, selection of potential microalgal species, mechanisms involved, and challenges in removing emerging pollutants using algal-bioremediation systems.


Asunto(s)
Contaminantes Ambientales , Microalgas , Purificación del Agua , Biodegradación Ambiental , Aguas Residuales
6.
Bioresour Technol ; 344(Pt B): 126305, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34752892

RESUMEN

Organic contaminants in water are a growing environmental threat to sustainable development, with detrimental effects on the biosphere. In recent years, researchers have increasingly focused their attention on the area of bioremediation as an important tool to eliminate harmful pollutants from the environment. This review examines the application of bioremediation technologies to the removal of organic pollutants, with an emphasis on hydrocarbons and textile dyes. It applies a descriptive bibliometric analysis to study statistical practicality-vs-applicability of bioremediation of emerging organic pollutants. The paper identifies efficient pathways for bioremediation of different types of organic pollutants and outlines the potential for an eco-friendly and economical approach for the biological remediation of micropollutants by microalgae. Facts and figures on various hazardous pollutants, constraints in their current removal from water at an industrial level, and promising future solutions are carefully presented here.


Asunto(s)
Contaminantes Ambientales , Microalgas , Biodegradación Ambiental , Hidrocarburos , Aguas Residuales
7.
Water Res ; 208: 117826, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34785404

RESUMEN

Environmental endocrine-disrupting chemicals (EDCs), a type of exogenous organic pollutants, are ubiquitous in natural aquatic environments. Therefor, this review focused on the use of the zebrafish as a model to explore the effect of different EDCs on behavior, as well as the molecular mechanisms that drive these effects. Furthermore, our study summarizes the current knowledge on the neuromodulatory effects of different EDCs in zebrafish. This study also reviews the current state of zebrafish behavior research, in addition to the potential mechanisms of single and mixed pollutant-driven behavioral dysregulation at the molecular level, as well as the applications of zebrafish behavior experiments for neuroscience research. This review broadens our understanding of the influence of EDCs on zebrafish behavior and provides guidance for future research.


Asunto(s)
Disruptores Endocrinos , Contaminantes Ambientales , Animales , Disruptores Endocrinos/toxicidad , Pez Cebra
8.
Chemosphere ; 287(Pt 3): 132324, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34563777

RESUMEN

Biological assays are useful in water quality evaluation by providing the overall toxicity of chemical mixtures in environmental waters. However, it is impossible to elucidate the source of toxicity and some lethal combination of pollutants simply using biological assays. As facile and cost-effective methods, computation model-based toxicity assessments are complementary technologies. Herein, we predicted the human health risk of binary pollutant mixtures (i.e., binary combinations of As(III), Cd(II), Cr(VI), Pb(II) and F(I)) in water using in vitro biological assays and deep learning methods. By employing a human cell panel containing human stomach, colon, liver, and kidney cell lines, we assessed the human health risk mimicking cellular responses after oral exposures of environmental water containing pollutants. Based on the experimental cytotoxicity data in pure water, multi-task deep learning was applied to predict cellular response of binary pollutant mixtures in environmental water. Using additive descriptors and single pollutant toxicity data in pure water, the established deep learning model could predict the toxicity of most binary mixtures in environmental water, with coefficient of determination (R2) > 0.65 and root mean squared error (RMSE) < 0.22. Further combining the experimental data on synergistic and antagonistic effects of pollutant mixtures, deep learning helped improve the predictive ability of the model (R2 > 0.74 and RMSE <0.17). Moreover, predictive models allowed us identify a number of toxicity source-related physiochemical properties. This study illustrates the combination of experimental findings and deep learning methods in the water quality evaluation.


Asunto(s)
Aprendizaje Profundo , Contaminantes Ambientales , Contaminantes Químicos del Agua , Humanos , Hígado , Contaminantes Químicos del Agua/toxicidad
9.
Chemosphere ; 287(Pt 3): 132300, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34563784

RESUMEN

Though many persistent organic pollutants (POPs) are closely regulated the human population is still exposed to these ubiquitous chemicals from the environment and diet. Safe management and human biomonitoring of POPs is necessary to understand the risk of exposure. Within human biomonitoring the mass of sample is often limited, therefore robust methods using smaller sample amounts are necessary. This study developed a 96-well plate solid phase extraction (SPE) method for determination of selected POPs: polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs), polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCD) and non-persistent novel flame retardants (NFRs) in low volume blood serum. Non-destructive clean-up coupling Oasis HLB extraction plate with Phree phospholipid removal plate was employed. Extraction efficiency was determined at low and high concentrations in certified reference materials NIST SRM 1957 and 1958, respectively. Target compounds deviated from certified values on average by 15% and 21% for SRM 1957 and SRM 1958, respectively. Observed limit of detections (LODs) ranged from 0.36 pg/mL (PCB 180) to 66.07 pg/mL (δ-HCH). The applicability for real samples is demonstrated on 48 samples from pregnant women enrolled in the pilot phase of the CELSPAC: TNG study. In total, 30 target compounds were detected in at least one sample. The method developed here provides a fast and reliable analysis of human blood serum with possibility to introduce automation for the sample preparation procedure.


Asunto(s)
Contaminantes Ambientales , Hidrocarburos Clorados , Plaguicidas , Bifenilos Policlorados , Femenino , Cromatografía de Gases y Espectrometría de Masas , Éteres Difenilos Halogenados/análisis , Humanos , Hidrocarburos Clorados/análisis , Contaminantes Orgánicos Persistentes , Plaguicidas/análisis , Bifenilos Policlorados/análisis , Embarazo , Suero/química , Extracción en Fase Sólida
10.
J Colloid Interface Sci ; 607(Pt 2): 1589-1602, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34587533

RESUMEN

It is of great significance to understand the role of carrier in piezocatalysis of composites by studying the separation mode of carriers under dynamic polarization field. Herein, the separation and migration pathways of carriers under piezoelectric field are investigated by synthesizing heterojunctions with Bi2WO6 (BWO) nanosheets grown vertically on g-C3N4 (CN) coated ZnO nanorods and directly on ZnO. Compared with the photocatalysis, the piezocatalytic efficiency of Rhodamine B (RhB) by BWO/ZnO is significantly increased to 0.121 min-1, which indicated the polarization field promotes band tilt and Z-scheme formation. After introducing the CN interlayer, the piezocatalytic efficiency of BWO/CN/ZnO is further improved (0.217 min-1), which can be attributed to the unique core-shell structure with Z-scheme heterojunctions. This unique structure provides more active sites and excited carrier concentration, the intermediate layer CN also reduces the direct contact and recombination of electrons and holes controlled by polarization potential at the interface between BWO and ZnO. This work deeply analyzes the influence of carrier concentration, separation efficiency and transport process on piezocatalysis, which provides a reference for the design of efficient catalysts.


Asunto(s)
Contaminantes Ambientales , Óxido de Zinc , Catálisis , Luz
11.
Chemosphere ; 287(Pt 4): 132375, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34597632

RESUMEN

Evidence of associations of pre- and postnatal exposure to polychlorinated biphenyls (PCBs) with cognitive development beyond early childhood is inconsistent. A previous report from this cohort observed adverse associations between early life PCB exposures and infant Bayley scores at age 16 months. The present study examines pre- and postnatal PCB exposures in relation to both behavior and cognitive development at age 45 months. Participants were 472 mother-child pairs residing in an area of eastern Slovakia characterized by environmental contamination with PCBs, which resulted in elevated blood serum concentrations. PCB-153 and PCB-118 concentrations were measured in maternal and in infant 6-, 16-, and 45-month serum samples. At age 45 months, children were administered five subtests of the Wechsler Preschool and Primary Scale of Intelligence (WPPSI-III), and mothers completed the Child Behavior Checklist (CBCL). Negative binomial and multiple linear regressions were used to estimate PCB-CBCL and PCB-WPPSI-III subtest score associations, respectively. Pre- and postnatal levels of PCB-153 and PCB-118 were not associated with cognitive performance on the WPPSI-III in this cohort. There was some suggestion that higher postnatal PCB concentrations were associated with more sleep problems and feelings of depression and anxiousness.


Asunto(s)
Contaminantes Ambientales , Bifenilos Policlorados , Efectos Tardíos de la Exposición Prenatal , Preescolar , Cognición , Estudios de Cohortes , Exposición a Riesgos Ambientales , Femenino , Humanos , Lactante , Embarazo , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Eslovaquia
12.
Chemosphere ; 287(Pt 4): 132385, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34597635

RESUMEN

Discharging of inorganic and organic pollutants creates a serious threat to the human health and the environment. In the current work, we have synthesized Ethylenediaminetetraacetic acid (EDTA) functionalized graphene oxide-chitosan nanocomposite (GO-EDTA-CS) for simultaneous removal of inorganic (i.e., mercury (Hg(II) and copper (Cu(II)) and organic pollutants (i.e., methylene blue (MB) and crystal violet (CV)) from wastewater via adsorption process. The structural, functional, morphological, elemental compositions, surface area and thermal properties of the synthesized nanocomposite were identified using powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), Brunauer-Emmett-Teller (BET), and thermogravimetric analyzer (TGA), respectively. Different batch adsorption experiments such as pH effect, contact time, initial pollutants concentration, reusability etc. were studied in monocomponent system to optimize the results. The adsorption process apparently followed pseudo-second-order (PSO) kinetics for both pollutants, however the adsorption kinetics was also explained by the intra-particle diffusion model. The isotherm data for both metals ions and dyes were well fit by the Langmuir isotherm model. The maximum adsorption capacities of the adsorbent were determined 324 ± 3.30 130 ± 2.80, 141 ± 6.60, and 121 ± 3.50 mg g-1 for Hg(II), Cu(II), MB, and CV, respectively. The excellent adsorption capacity was attributed to the availability of various active functional groups (e.g., -COOH, -OH, -NH2, etc.) on the adsorbent. The EDS, elemental mapping and FTIR analysis performed before and after the adsorption of heavy metals and dyes by GO-EDTA-CS confirmed the simultaneous adsorption of the pollutants. Moreover, GO-EDTA-CS could maintain its adsorption capacity for both inorganic and organic pollutants even after seven cycles of adsorption-desorption, indicating itself a promising adsorbent for practical wastewater treatment containing both inorganic and organic toxic pollutants.


Asunto(s)
Quitosano , Contaminantes Ambientales , Nanocompuestos , Contaminantes Químicos del Agua , Adsorción , Ácido Edético , Grafito , Humanos , Cinética , Espectroscopía Infrarroja por Transformada de Fourier , Aguas Residuales , Contaminantes Químicos del Agua/análisis
13.
Chemosphere ; 287(Pt 4): 132387, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34600004

RESUMEN

MXene-based nanomaterials (MBNs) are two-dimensional materials that exhibit a series of sought after properties, including rich surface chemistry, adjustable bandgap structures, high electrical conductivity, hydrophobicity, thermal stability, and large specific surface area. MBNs have an exemplar performance when applied for the degradation of hazardous pollutants with various advanced oxidation processes such as heterogeneous sonocatalysis. As such, this work focuses on the sonocatalytic degradation of various hazardous pollutants using MXene-based catalysts. First, the general principles of sonocatalysis are examined, followed by an analysis of the main components of the MXene-based sonocatalysts and their application for pollutant degradation. Lastly, ongoing challenges are highlighted with recommendations to address the issues.


Asunto(s)
Contaminantes Ambientales , Nanoestructuras , Catálisis , Conductividad Eléctrica
14.
Environ Pollut ; 292(Pt A): 118267, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34601036

RESUMEN

Distillery sludge is a major source of aquatic pollution, but little is known about their microbial community and their association with the organic and metal pollutants. Sugarcane molasses-based distillery is an important industry in India, although the waste is usually treated prior to disposal, the treatment is often inadequate. The adverse effects of the organic and metal pollutants in sugarcane molasses-based distillery sludge on the microbial biodiversity and abundance in the disposal site have not been elucidated. This study aims to address this gap of knowledge. Samples were collected from the discharge point, 1 and 2 km downstream (D1, D2, and D3, respectively) of a sugarcane distillery in Uttar Pradesh, India, and their physico-chemical properties characterised. Using QIIME, taxonomic assignment for the V3 and V4 hypervariable regions of 16 S rRNA was performed. The phyla Proteobacteria (28-39%), Firmicutes (20-28%), Bacteriodetes (9-10%), Actinobacteria (5-10%), Tenericutes (1-9%) and Patescibacteria (2%) were the predominant bacteria in all three sites. Euryechaeota, were detected in sites D1 and D2 (1-2%) but absent in D3. Spirochaetes (5%), Sinergistetes (2%) and Cloacimonetes (1%) were only detected in samples from site D1. Shannon, Simpson, Chao1, and Observed-species indices indicated that site D1 (10.18, 0.0013, 36706.55 and 45653.84, respectively) has higher bacterial diversity and richness than D2 (6.66, 0.0001, 25987.71 and 49655.89, respectively) and D3 (8.31, 0.002, 30345.53 and 30654.88, respectively), suggesting the organic and metal pollutants provided the stressors to favour the survival of microbial community that can biodegrade and detoxify them in the distillery sludge. This study confirmed that the treatment of the distillery waste was not sufficiently effective and provided new metagenomic information on its impact on the surrounding microbial community. It also offered new insights into potential bioremediation candidates.


Asunto(s)
Contaminantes Ambientales , Microbiota , Saccharum , Melaza , Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Aguas Residuales
15.
Environ Pollut ; 292(Pt A): 118264, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34606968

RESUMEN

Preterm birth is the second most common cause of death in children under 5 years of age. The etiology of preterm birth has not yet been elucidated. Although maternal exposure to endocrine disrupting chemicals (EDCs) may increase the risk for preterm birth, associations have not been confirmed. We performed a meta-analysis to elucidate the relationships between maternal exposure to EDCs and preterm birth. A systematic search of PubMed, Ovid-EMBASE, and the Cochrane Library (CENTRAL) for relevant published studies providing quantitative data on the association between maternal EDC exposure and preterm birth in humans was conducted in July 2021. To calculate the overall estimates, we pooled the adjusted regression coefficients with 95% confidence intervals (CIs) from each study by the inverse variance method. A total of 59 studies were included. The pooled results indicated that maternal exposure to metals (OR, 1.23; 95% CI, 1.17 to 1.29) and phthalates (OR, 1.31; 95% CI, 1.21 to 1.42) was related to an increased risk for preterm birth. Specifically, maternal exposure to lead, cadmium, chromium, copper and manganese appeared to be correlated with an elevated risk for preterm birth. Additionally, maternal exposure to monoethyl phthalate (MEP), mono-2-ethyl-5-carboxypentyl phthalate (MECPP), monobenzyl phthalate (MBzP), and di (2-ethylhexyl) phthalate (DEHP) was also associated with preterm birth. In conclusion, maternal exposure to metals and phthalates may increase the risk for preterm birth based on current evidence.


Asunto(s)
Disruptores Endocrinos , Contaminantes Ambientales , Ácidos Ftálicos , Nacimiento Prematuro , Niño , Preescolar , Exposición a Riesgos Ambientales , Femenino , Humanos , Recién Nacido , Exposición Materna , Ácidos Ftálicos/toxicidad , Embarazo , Nacimiento Prematuro/inducido químicamente , Nacimiento Prematuro/epidemiología , Análisis de Regresión
16.
Chemosphere ; 287(Pt 4): 132457, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34610373

RESUMEN

Lead (Pb) is the most widely used anode in zinc (Zn) electrowinning and other metallurgical industries. The resource loss and environmental pollution caused by Pb anode corrosion are urgent problems to be solved. A γ-MnO2 precoated anode was prepared successfully to reduce the Pb-containing pollutant. The size effects with its controllable preparation on an industrial scale were studied. Severe nonuniform distribution of γ-MnO2 film was observed with curbing the reduction of anode slime only 68%, when anode size increased from lab to industry. Nonuniform rate (R) and average thickness (d) were found to be the key indicators to determine the film structure distribution and their performance differences, which were random and difficult to be controlled in scale-up size. However, a controllable industrial γ-MnO2 precoated anodes (IMPA) fabricated through optimized current density (J0) and electrodeposition time (t) in our developed film-forming system. Then, the long-term performances of two IMPA with different indicators (IMPA-1: R = 34%, d = 108 µm, IMPA-2: R = 23%, d = 55 µm) were compared with the industrial typical Pb-based anode (ITPA). Of the three different anodes, the optimized IMPA-2 displayed the best performance. Within 24 d of electrowinning cycle, the corrosion inhibition effect and the anode slime reduction rate for IMPA-2 improved by 56% and 30% than IMPA-1, and improved by 100% and 91% than ITPA. Furthermore, the mechanism analysis of size effect change showed that R of IMPA was contributed to the local gas holdup distribution along the anode. Controlled size effect of uniform oxide film will have a future application prospect for the sustainability of industry, which provides an important cleaner production of Zn electrowinning and related hydrometallurgy industries.


Asunto(s)
Contaminantes Ambientales , Zinc , Electrodos , Plomo , Compuestos de Manganeso , Metalurgia , Óxidos
17.
J Environ Manage ; 301: 113869, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34619588

RESUMEN

Untreated domestic wastewater and agricultural runoff are emerging as a potent cause of non-point source (NPS) pollutants which are a major threat to aquatic ecosystems. Periphyton biofilm-based technologies due to their high growth rate, energy efficiency and low input costs offer promising solutions for controlling nutrient pollution in agricultural systems. In this study we employed periphyton floway to treat NPS pollution from the agricultural watershed. The process performance of outdoor single pass algae floway (AFW) was evaluated. Steady state average biomass concentration of 11.73 g m-2 d-1 and removal rate of nitrogen: 0.60 g m-2 d-1, phosphorus: 0.27 g m-2d-1, arsenic: 9.26 mg m-2 d-1, chromium: 255.3 mg m-2 d-1 and lead: 238.6 mg m-2 d-1 was achieved. In addition, the microalgae and their associated bacterial diversity and dynamics were analyzed. The results revealed a high diversity and rapid variations in the microbiome structure with diatom and cyanobacteria dominance combined with high N fixing and P solubilizing bacteria during most of the operational period. Elemental analysis of periphyton biomass was done for its safe use as slow-release fertilizer. Biofuel feedstock potential and nanoparticle generation potential of the biomass were analyzed. This work highlights the potential use of periphyton biofilms in remediation and recycling of NPS pollutants with simultaneous resource recovery.


Asunto(s)
Contaminantes Ambientales , Perifiton , Contaminantes Químicos del Agua , Biopelículas , Biomasa , Ecosistema , Fósforo , Contaminantes Químicos del Agua/análisis
18.
J Environ Manage ; 301: 113796, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34626951

RESUMEN

Arsenic (As) is one of the most investigated elements worldwide due to its negative impact on the natural system. Its geochemical behavior depends on several geogenic processes, which can cause hazardous enrichment into natural waters, even in remote areas, far from anthropogenic sources. In this work the arsenic pollution issue has been addressed by studying water-rock interaction processes and applying reaction path modelling as a tool to understand the rock-to-water release of As and the fate of this natural pollutant in crystalline aquifers. In-depth geochemical characterization of several water samples discharging from crystalline aquifers was performed. The obtained data were used to fix the boundary conditions and validate the modelling outcomes. The performed modelling allowed to reconstruct the water-rock interaction processes which occur (i) in shallow and relatively shallow crystalline aquifers in which no As anomalies were observed and (ii) in As-rich areas, coupling reaction path modelling of granite dissolution with adsorption of dissolved As onto precipitating crystalline and amorphous Fe(III)-oxyhydroxides given the widespread presence of these phases in the studied environment. The results of the geochemical modelling are in agreement with the analytical data and reproduce them satisfactorily. The performed geochemical modelling is of high environmental significance because it is a flexible and powerful tool that correctly defines the water-rock interaction processes occurring in crystalline aquifers, providing valuable data to improve the knowledge on As behavior, not only in the study area, but also in similar geological settings worldwide. Therefore, the present research has broad future perspectives in the environmental field.


Asunto(s)
Arsénico , Contaminantes Ambientales , Agua Subterránea , Contaminantes Químicos del Agua , Arsénico/análisis , Monitoreo del Ambiente , Compuestos Férricos/análisis , Contaminantes Químicos del Agua/análisis
19.
Environ Pollut ; 292(Pt A): 118315, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34634397

RESUMEN

Fluorinated pesticides acquired a significant market share in the agrochemical sector due to the surge of new fluoroorganic ingredients approved in the last two decades. This growing trend has not been accompanied by a comprehensive scientific and regulatory framework entailing all their potential negative impacts for the environment, especially when considering the hazardous properties that may result from the incorporation of fluorine into organic molecules. This review aims to address the safe/hazardous dichotomy associated with fluorinated pesticides by providing an updated outlook on their relevancy in the agrochemical sector and how it leads to their role as environmental pollutants. Specifically, the environmental fate and distribution of these pesticides in the ecosystems is discussed, while also analysing their potential to act as toxic substances for non-target organisms.


Asunto(s)
Contaminantes Ambientales , Plaguicidas , Contaminantes Químicos del Agua , Ecosistema , Contaminación Ambiental , Plaguicidas/análisis , Contaminantes Químicos del Agua/análisis
20.
Bioresour Technol ; 343: 125913, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34649060

RESUMEN

Biofilm wastewater treatment had been applied in practice. Conventionally the biofilm was modeled as a uniform structure to simplify the analysis. This study for the first time established a three-dimensional biofilm model with distributions separating living cells, Extracellular polymeric substances (EPS) and pores, based on which the local fluid flow velocity and pollutant diffusion and reaction fluxes inside the biofilm were numerically evaluated. Both the uniform structured and previously proposed heterogeneous models had been confirmed to overestimate the performances of a biofilm for wastewater treatment. The survival strategies of living cells in biofilm were discussed. Besides exposing to fresh pollutants for maximizing pollutant uptake, the tendency to form small aggregates of cells for shortening diffusion length so furnishing the pollutant with reduced diffusional resistance to living cells was also for the first time noted. This communication advanced the knowledge to comprehend the detailed processes in biofilm.


Asunto(s)
Contaminantes Ambientales , Biopelículas , Reactores Biológicos , Difusión , Matriz Extracelular de Sustancias Poliméricas
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