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1.
J Environ Sci (China) ; 148: 591-601, 2025 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39095192

RESUMO

To explore air contamination resulting from special biomass combustion and suspended dust in Lhasa, the present study focused on the size distribution and chemical characteristics of particulate matter (PM) emission resulting from 7 types of non-fossil pollution sources. We investigated the concentration and size distribution of trace elements from 7 pollution sources collected in Lhasa. Combining Lhasa's atmospheric particulate matter data, enrichment factors (EFs) have been calculated to examine the potential impact of those pollution sources on the atmosphere quality of Lhasa. The highest mass concentration of total elements of biomass combustion appeared at PM0.4, and the second highest concentration existed in the size fraction 0.4-1 µm; the higher proportion (12 %) of toxic metals was produced by biomass combustion. The elemental composition of suspended dust and atmospheric particulate matter was close (except for As and Cd); the highest concentration of elements was all noted in PM2.5-10 (PM3-10). Potassium was found to be one of the main biomass markers. The proportion of Cu in suspended dust is significantly lower than that of atmospheric particulate matter (0.53 % and 3.75 %), which indicates that there are other anthropogenic sources. The EFs analysis showed that the Cr, Cu, Zn, and Pb produced by biomass combustion were highly enriched (EFs > 100) in all particle sizes. The EFs of most trace elements increased with decreasing particle size, indicating the greater influence of humanfactors on smaller particles.


Assuntos
Aerossóis , Poluentes Atmosféricos , Poeira , Monitoramento Ambiental , Tamanho da Partícula , Material Particulado , Poluentes Atmosféricos/análise , Aerossóis/análise , Material Particulado/análise , Poeira/análise , Oligoelementos/análise , Poluição do Ar/estatística & dados numéricos , Poluição do Ar/análise , China , Atmosfera/química
2.
J Environ Sci (China) ; 149: 500-511, 2025 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39181662

RESUMO

Formic and acetic acids are the most abundant gaseous organic acids and play the key role in the atmospheric chemistry. In iodine-adduct chemical ionization mass spectrometry (CIMS), the low utilization efficiency of methyl iodide and humidity interference are two major issues of the vacuum ultraviolet (VUV) lamp initiated CIMS for on-line gaseous formic and acetic acids analysis. In this work, we present a new CIMS based on VUV lamp, and the ion-molecular reactor is separated into photoionization and chemical ionization zones by a reducer electrode. Acetone was added to the photoionization zone, and the VUV photoionization acetone provided low-energy electrons for methyl iodide to generate I-, and the addition of acetone reduced the amount of methyl iodide by 2/3. In the chemical ionization zone, a headspace vial containing ultrapure water was added for humidity calibration, and the vial changes the sensitivity as a function of humidity from ambiguity to well linear correlation (R2 > 0.95). With humidity calibration, the CIMS can quantitatively measure formic and acetic acids in the humidity range of 0%-88% RH. In this mode, limits of detection of 10 and 50 pptv are obtained for formic and acetic acids, respectively. And the relative standard deviation (RSD) of quantitation stability for 6 days were less than 10.5%. This CIMS was successfully used to determine the formic and acetic acids in the underground parking and ambient environment of the Shandong University campus (Qingdao, China). In addition, we developed a simple model based formic acid concentration to assess vehicular emissions.


Assuntos
Espectrometria de Massas , Espectrometria de Massas/métodos , Poluentes Atmosféricos/análise , Iodetos/análise , Iodetos/química , Raios Ultravioleta , Formiatos/análise , Formiatos/química , Atmosfera/química , Monitoramento Ambiental/métodos , Processos Fotoquímicos , Ácido Acético/análise , Ácido Acético/química , Hidrocarbonetos Iodados/análise , Hidrocarbonetos Iodados/química
3.
J Hazard Mater ; 480: 136039, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39366051

RESUMO

Copper (Cu) and zinc (Zn), two potentially toxic trace elements, are commonly abundant in organic wastes (OWs) recycled in soils as fertilizer. Yet current knowledge on the long-term behavior and fate of Cu and Zn in soil following OW spreading is scant. We addressed this issue by studying the fate of OW-borne Cu and Zn in amended soils from four different long-term field experiments. By combining the stable isotope analysis and X-ray absorption spectroscopy, we identified changes in Cu and Zn concentrations, speciation and isotopic compositions in the amended soils only when OW had been applied at high rates over long periods. Under these conditions, we highlighted that: (i) all OW-derived Cu and Zn had accumulated in the topsoil layer regardless of the soil and OW type; (ii) the amended soil isotopic signatures were the result of the mixing of OW-borne and natural Cu and Zn; and (iii) Cu and Zn exhibited distinct speciation patterns in amended soils. Indeed, the unprecedented persistence of OW-borne crystallized Cu(I)-sulfide in the amended soils contrasted with the complete transformation of pig slurry-borne nanosized Zn-sulfide or household compost-derived amorphous Zn phosphate and Zn complexed by organic matter.

4.
Water Res ; 267: 122542, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39366325

RESUMO

To mitigate groundwater level decline, managed aquifer recharge (MAR) with secondary treated wastewater (STWW) is increasingly considered and implemented. However, the effectiveness and potential risks of such systems need evaluation prior to implementation. In this study, we present a large-scale sand tank experiment to analyse processes related to the infiltration of real STWW through the vadose zone and subsequent mixing with oxic native groundwater. The varying composition of STWW from 15 infiltration cycles over six months of operation and the retention times were the main drivers of the observed processes, which were characterized by a wide range of analytical techniques such as in situ high-resolution oxidation-reduction potential (ORP) measurements, closed mass balances of solutes, characterization of dissolved organic carbon (DOC), stable nitrate isotopes analysis, as well as numerical flow and transport modelling. Depending on the composition and infiltration rates of the STWW, both nitrification and denitrification could be observed, even simultaneously at different locations in the tank. Furthermore, due to the variability of the real STWW we observed enhanced arsenic mobilisation during times of elevated phosphate concentrations of the infiltrating STWW. Additionally, uranium was mobilised in our experimental system via carbonate mineral dissolution caused by the infiltrating STWW which was undersaturated of calcite for all infiltration cycles. Overall, our results showed the importance of conducting studies with waters of complex matrix, such as real STWW, and considering mixing with groundwater to assess the full range of possible processes encountered at MAR field sites.

5.
Arh Hig Rada Toksikol ; 75(3): 159-171, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39369326

RESUMO

Neutral bis(amino acidato)copper(II) [Cu(aa)2] coordination compounds are the physiological species of copper(II) amino acid compounds in blood plasma taking the form of bis(l-histidinato)copper(II) and mixed ternary copper(II)-l-histidine complexes, preferably with l-glutamine, l-threonine, l-asparagine, and l-cysteine. These amino acids have three functional groups that can bind metal ions: the common α-amino and carboxylate groups and a side-chain polar group. In Cu(aa)2, two coordinating groups per amino acid bind to copper(II) in-plane, while the third group can bind apically, which yields many possibilities for axial and planar bonds, that is, for bidentate and tridentate binding. So far, the experimental studies of physiological Cu(aa)2 compounds in solutions have not specified their complete geometries. This paper provides a brief review of my group's research on structural properties of physiological Cu(aa)2 calculated using the density functional theory (DFT) to locate low-energy conformers that can coexist in aqueous solutions. These DFT investigations have revealed high conformational flexibility of ternary Cu(aa)2 compounds for tridentate or bidentate chelation, which may explain copper(II) exchange reactions in the plasma and inform the development of small multifunctional copper(II)-binding drugs with several possible copper(II)-binding groups. Furthermore, our prediction of metal ion affinities for Cu2+ binding with amino-acid ligands in low-energy conformers with different coordination modes of five physiological Cu(aa)2 in aqueous solution supports the findings of their abundance in human plasma obtained with chemical speciation modelling.


Assuntos
Aminoácidos , Cobre , Cobre/química , Cobre/sangue , Aminoácidos/química , Aminoácidos/sangue , Humanos , Complexos de Coordenação/química , Complexos de Coordenação/sangue
6.
Artigo em Inglês | MEDLINE | ID: mdl-39361200

RESUMO

This study focused on 120 specimens of the shrimp Palaemon elegans collected in intertidal zones in eight selected areas. This study aimed to assess the suitability of P. elegans as a bioindicator of natural and anthropogenic marine pollution. Metal concentrations of aluminum (Al), cadmium (Cd), copper (Cu), iron (Fe), lead (Pb), and zinc (Zn) were measured in shrimp collected from various sites in the Canary Islands, including areas affected by volcanic activity, industrial activity, and control zones. The determination of metal concentrations was conducted using inductively coupled plasma optical emission spectrophotometry (ICP-OES). The results showed significant differences in metal concentrations across the studied sites, with the highest levels of Al, Cu, Fe, Pb, and Zn observed in areas impacted by the Tajogaite volcanic eruption and harbor activity. Sites near old landfills and sewage pipes also exhibited elevated levels of Cd, Cu, and Pb, indicating strong anthropogenic influence. Al was found in the highest concentration in Harbour, reaching 25.7 ± 6.2 mg/kg, while the lowest concentration was observed in Control Lp at 11.5 ± 0.69 mg/kg. Conversely, lower metal concentrations were detected in control zones and areas with high dinoflagellate presence, suggesting a potential role of bioremediation by marine phytoplankton. The ability of P. elegans to accumulate metals in its tissues, particularly in areas of high pollution, highlights its potential as a bioindicator species. This study underscores the importance of P. elegans in monitoring marine pollution and provides insights into the environmental impact of both natural and human-induced contamination on coastal ecosystems.

7.
Artigo em Inglês | MEDLINE | ID: mdl-39365535

RESUMO

Microplastics (MP) pollution is a pressing concern in today's marine environments. MPs can significantly affect marine ecosystems by altering nutrient and pollutant dynamics. This review analyses the existing literature to investigate interactions between MPs and micronutrients/pollutants, specifically trace and toxic metals in marine environments. It explores the adsorption of metals onto MP surfaces, emphasizing kinetics, isotherms, and underlying mechanisms of the process. The review highlights the potential consequences of MPs on the biogeochemical cycles of trace and toxic metals, emphasizing disruptions that could result in metal toxicity, metal limitations, reduced bioavailability, and adverse effects on primary productivity in marine ecosystems. It further underscores the need for future research to unravel the wide-ranging implications of MPs on trace and toxic metal cycling in marine ecosystems and their broader environmental impacts.

8.
Sci Rep ; 14(1): 22867, 2024 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-39354012

RESUMO

Dust particles and their associated compounds can adversely affect human health and ecosystems. The aim of this study was to investigate the concentration, health, and ecological risks of selected potentially toxic elements (e.g. Pb, Cd, Cr, Co, Cu, Zn, V, Ni, and As) bound to air particles generated by dust storms in the Sejzi plain desert area within the industrial district of Isfahan metropolitan, Iran. The enrichment factor revealed the highest values for Zn, Pb, and Cd which among them Zn showed the highest value (8.1) with the potential source of industrial activities confirmed by the integrated pollution index, accumulation coefficient, and ecological risk index. Regarding health risk analysis (non-cancer and cancer risks) the elements including Co, As, and Cr showed a significant risk for adults and children across all seasons. It's concluded that mitigation of air particles originated from both natural and industrial activities is necessary to reduce their relevant risks to human being and ecosystems in the region.


Assuntos
Poluentes Atmosféricos , Poeira , Irã (Geográfico) , Poeira/análise , Humanos , Medição de Risco , Poluentes Atmosféricos/análise , Poluentes Atmosféricos/efeitos adversos , Monitoramento Ambiental/métodos , Metais Pesados/análise , Metais Pesados/toxicidade , Clima Desértico , Exposição Ambiental/efeitos adversos , Material Particulado/análise , Material Particulado/efeitos adversos , Indústrias , Criança , Adulto
9.
Photoacoustics ; 40: 100650, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39351139

RESUMO

This paper proposes a novel microcone-curved resonant photoacoustic cell (MCR-PAC) for highly sensitive trace gas detection. The MCR-PAC features with microcone-curved resonant region and cylindrical buffer chamber, which dominates the photoacoustic signal amplification. By introducing the hyperbolic eccentricity as a new optimization dimension, the quality factor of the MCR-PAC is remarkably strengthened to enhance the acoustic pressure amplitude. At an eccentricity value of 5, the volume of the photoacoustic resonant cavity is approximately 0.23 cm3. Targeting trace acetylene, the system achieves a minimum detection limit of 1.41 ppb with an integration time of 290 s, corresponding normalized noise equivalent absorption coefficient is 1.88×10-9 W·cm-1·Hz-1/2. Compared to the traditional T-type PAC, the overall performance of MCR-PAC has been enhanced nearly fourfold. With its compact millimeter-scale dimensions and high sensitivity, the MCR-PAC demonstrates extensive potential for application in environmental monitoring and breath diagnostics.

10.
J Hazard Mater ; 480: 135960, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39353272

RESUMO

Current total concentration-based methods for source attribution and risk assessment often overestimate metal risks, thereby impeding the formulation of effective risk management strategies. This study aims to develop a framework for source-specific risk assessment based on metal bioavailability in surface river sediments from a human-dominated seaward catchment in eastern China. Metal bioavailability was quantified using chemical fractionation results, and source apportionment was conducted using the positive matrix factorization (PMF) model. Risk assessment integrated these findings using two indices: the Potential Ecological Risk Index (PERI) and the Mean Probable Effect Concentration Quotient (mPEC-Q), with uncertainty addressed via Monte Carlo simulations. Results indicated that average total concentrations of Cu, Pb, Zn, Cr, Hg, Cd, and As exceeded their respective background levels by 1.63 to 15.00 times. The residual fraction constituted the majority, accounting for 53.84 % to 77.79 % of total concentrations, suggesting significant natural origins. However, source apportionment revealed a predominant contribution from anthropogenic activities, including industrial smelting, agricultural practices, and atmospheric deposition. The contributions were found to vary between 5.35 % and 40.03 % when the total concentration was adjusted to bioavailable content. Total concentration-based PERI/mPEC-Q assessments indicated high/moderate risk levels, decreasing to considerable/low risk levels with bioavailability adjustment. Hg and Cd were identified as priority metals. Further incorporating source appointment parameters into the risk assessment, industrial smelting was identified as the primary contributor, accounting for 66.06 % of total risk by total concentration and 65.63 % by bioavailability. This underscores the role of bioavailability in mitigating risk overestimation. Monte Carlo simulations validated industrial smelting as a major risk contributor. This study emphasizes the importance of considering bioavailability in the source-risk assessment of sediment-metals, crucial for targeted risk management in urbanized catchment areas.

11.
Food Chem ; 463(Pt 4): 141460, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39357309

RESUMO

This review focuses on trace element speciation in edible mushrooms, providing information on analytical methods, available literature data, and health risk assessment. All steps of analytical procedures were presented, including extraction, separation and quantification. It compiles fragmented literature data on trace element speciation, focusing on arsenic, chromium, selenium, mercury, and antimony. Key findings include non-bioaccumulative chromium, the prevalence of Sb(V), mercury accumulation in contaminated sites, diverse arsenic and selenium speciation. Safe intake limits by agencies like USEPA indicate low risk for Cr(VI) and Sb but significant hazards from mercury and methylmercury, especially in contaminated areas: about 10 % of samples exceed safe limits for inorganic arsenic, and selenium enrichment often surpasses safety thresholds. The review underscores the need for standardized methods, speciation analyses of all toxicologically relevant species, and research on cooking impacts to improve health risk evaluations: establishing safe conditions for mushroom consumption remains a far-fetched goal.

12.
Sci Total Environ ; : 176701, 2024 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-39370007

RESUMO

Trace metals and metalloids occur in small quantities in the subsurface water generated from oil wells, called produced water (PW). While these substances are present in low concentrations, PW volumes are sufficiently large that they are still a potential environmental concern. This study has focused on quantifying 71 trace metals and metalloids present in PW from Danish offshore oil production sites. These metals are often a challenge to measure and are globally underreported. By employing optimized sample treatment and ICP-OES and ICP-SFMS methods, the full elemental screening of PW samples collected from various offshore platforms has been carried out with high accuracy. Distinct geochemical signatures involving 35 elements have been discovered and they are associated with significant site-specific variations in the concentrations of key trace metals, including W, Ba, Mo, Cu, and Tl. Utilizing Principal Component Analysis (PCA), the study has effectively distinguished between PW samples from different fields, highlighting the relevance of certain trace metals and elemental ratios as potential geochemical markers. Geochemical analysis of the chalk rock material from the same production wells as the fluid samples has shown a correlation of key elements Tl, W, Cu, Mo, Ba, and As in the chalk with the produced water, indicating the origin of the metals. The study has revealed a high compositional variability of PW and found that elements including Zn, Co, Hg, and Cs occur in concentrations of magnitude higher than previous estimates. In addition, there is high variability in concentrations at different sampling times, underlining the need for environmental monitoring and developing more informed management strategies for the main offshore PW stream. The variability in concentrations in space and time leads to large uncertainties in environmental reporting based on a few samples. The detailed sampling campaign reported here for the first time highlights need for much more frequent sampling, ideally continuous monitoring. The safety of produced water discharge to sea can be significantly underestimated by limited sampling. This paper provides the first field-specific and time varied screening of heavy metals in real produced water and shows the discrepancy in our understanding of the environmental impact of PW.

13.
Pharmacol Rep ; 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39352642

RESUMO

BACKGROUND: Ethanol disrupts brain activity and memory. There is evidence supporting the beneficial effect of levetiracetam on alcohol consumption. Therefore, the aim of the study was to examine whether levetiracetam has a protective activity against ethanol-induced memory impairment, alterations in selected neurotransmission activities, oxidative stress, and selected essential elements in rats. METHODS: The rats were given levetiracetam (300 mg/kg b.w. po) with ethanol for three weeks prior to behavioral tests. Spatial memory was tested using the Morris water maze, while recognition memory was evaluated using the Novel object recognition test. The GABA and glutamate concentration was determined in three rat brain regions (cerebellum, hippocampus, and cerebral cortex). Serum oxidative stress parameters and selected essential elements concentration (Cu, Mn, Zn, Fe, Mg) in the rat brain were analyzed. RESULTS: Levetiracetam administered with ethanol improved spatial memory, but did not affect abstinence-induced impairment. The drug also decreased ethanol-induced long-term recognition memory impairment. No alterations in glutamate levels were observed. GABA levels were elevated by levetiracetam in the cerebral cortex and by ethanol in the cerebellum. Ethanol increased catalase activity (CAT) and decreased superoxide dismutase activity (SOD) in the serum. Levetiracetam significantly increased the activity of SOD. Alcohol disrupted the levels of trace elements (Mn, Zn, Mg) in the rat brain. Additionally, levetiracetam alone increased Mg, Fe, and Cu concentrations while all animals receiving the drug also had significantly lower concentrations of Zn. CONCLUSIONS: Levetiracetam had differential effects against ethanol-induced impairments. These findings could have important implications for future levetiracetam treatment in patients.

14.
Nano Lett ; 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39374070

RESUMO

The composition and physiochemical properties of the solid electrolyte interphase (SEI) significantly impact the electrochemical cyclability of the Li metal. Here, we introduce a trace dual-salt electrolyte additive (TDEA) that accelerates LiF production from FEC decomposition and improves the LiF distribution, resulting in earlier LiF precipitation and the formation of a LiF-rich SEI on the Li anode. TDEA at a millimolar-level concentration was found to alter the morphology of deposited Li, suppress Li dendrite formation, and increase the cycling time and operating current density for Li anodes. Li∥NCM811 full cells using TDEA-based electrolytes exhibited approximately two times longer lifespan than those without additives. Additionally, the TDEA-based electrolytes enabled a high energy density of 347 Wh kg-1 for 500-mAh pouch cells, maintaining stable cycling over 180 cycles under stringent conditions (N/P = 1.26 and E/C = 2.2 g A h-1). Our findings suggest that the proposed TDEA strategy offers a promising path to achieving high-performance Li metal batteries.

15.
Environ Geochem Health ; 46(11): 438, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39316175

RESUMO

The concentrations of heavy metals (HMs) can be increased by various anthropogenic activities such as mining, fuel combustion, pesticide use, and urban development, which can alter the mechanisms determining their spatial variability in the environment. Determining natural concentrations, monitoring, and assessing potential ecological risks are essential in the management of pollution prevention policies and soil conservation in watersheds. The aim of this study was to determine HMs natural concentrations, establish quality reference values (QRVs), and evaluate pollution indices in a watershed-scale. Composite surface soil samples (n = 115) were collected from areas: native vegetation, pasture, perennial crops, urbanization, planted forest, annual crops, and desertification. The soil samples digestion followed the EPA 3051A, and metals determination in ICP-OES. The data were subjected to the Kruskal-Wallis test, Spearman's correlation, multivariate clustering analysis and. geostatistics. The QRVs established (75th) for the Gurgueia River watershed in descending order were (mg kg-1): V (26.16) > Cr (18.06) > Pb (6.24) > Zn (3.86) > Cu (2.66) > Ni (1.45) > Co (0.57) > Mo (0.46) > Cd (0.07). The concentrations of Cd, Co, Cr, Mo, Ni, V, and Zn in types of land and management practices were significantly increased compared to those in natural vegetation. Overall, the watershed falls into the categories of minimal to moderate enrichment, moderate to considerable contamination, and low to moderate potential ecological risk, with Cd presenting elevated values. The percentages of polluted samples ranged from 14.3 to 82.5%, indicating the need for monitoring these areas to ensure environmental quality and food safety.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Metais Pesados , Rios , Poluentes do Solo , Metais Pesados/análise , Brasil , Medição de Risco , Poluentes do Solo/análise , Sedimentos Geológicos/química , Rios/química , Solo/química , Poluentes Químicos da Água/análise
16.
Sensors (Basel) ; 24(17)2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39275538

RESUMO

Wearable sensors for sweat trace metal monitoring have the challenges of effective sweat collection and the real-time recording of detection signals. The existing detection technologies are implemented by generating enough sweat through exercise, which makes detecting trace metals in sweat cumbersome. Generally, it takes around 20 min to obtain enough sweat, resulting in dallied and prolonged detection signals that cannot reflect the endogenous fluctuations of the body. To solve these problems, we prepared a multifunctional hydrogel as an electrolyte and combined it with a flexible patch electrode to realize real-time monitoring of sweat Zn2+. Such hydrogel has magnetic and porous properties, and the porous structure of hydrogel enables a fast absorption of sweat, and the magnetic property of the addition of fabricated Fe3O4 NPs not only improves the conductivity but also ensures the adjustable internal structures of the hydrogel. Such a sensing platform for sweat Zn2+ monitoring shows a satisfied linear relationship in the concentration range of 0.16-16 µg/mL via differential pulsed anodic striping voltammetry (DPASV) and successfully detects the sweat Zn2+ of four volunteers during exercise and resting, displaying a promising path for commercial application.


Assuntos
Hidrogéis , Suor , Dispositivos Eletrônicos Vestíveis , Zinco , Suor/química , Humanos , Magnetismo , Zinco/análise , Óxido Ferroso-Férrico/química , Técnicas Biossensoriais
17.
Sci Total Environ ; 953: 175924, 2024 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-39233086

RESUMO

Sewer overflows are an environmental concern due to their potential to introduce contaminants that can adversely affect downstream aquatic ecosystems. As these overflows can occur during rainfall events, the influence of rainwater ingress from inflow and infiltration on raw untreated wastewater (influent) within the sewer is a critical factor influencing the dilution and toxicity of the contaminants. The Vineyard sewer carrier in the greater city of Sydney, Australia, was selected for an ecotoxicological investigation of a sanitary (separate from stormwater) sewerage system and a wet-weather overflow (WWO). Three influent samples were collected representing dry-weather (DW), intermediate wet-weather (IWW) and wet-weather (WW). In addition, a receiving water sample was also collected downstream in Vineyard Creek (WW-DS) coinciding with a WWO. We employed direct toxicity assessment (DTA) and toxicity identification evaluation (TIE) approaches to gain comprehensive insights into the nature and magnitude of the impact on influent from rainwater ingress into the sewer. Three standard ecotoxicological model species, a microalga, Chlorella vulgaris, the water flea, Ceriodaphnia dubia and the midge larva, Chironomus tepperi were used for both acute and chronic tests. The study revealed variable toxicity responses, with the sample of influent collected in wet-weather displaying lower toxicity compared to the dry-weather sample of influent. Ammonia, and metals, were identified in dry weather as contributors to the observed toxicity, however, this risk was alleviated through rainwater ingress in wet-weather with further dilution within the receiving water. Based on toxicity data, dilutions of influent to minimise effects on C. vulgaris and C. dubia ranged from 1 in 12 in DW to 1 in 2.8 in WW, and further diminished in the receiving water to 1 in 1.8. The successful application of ecotoxicological approaches enabled the assessment of cumulative effects of contaminants in influent, offering valuable insights into the sanitary sewer system under rainwater ingress.


Assuntos
Ecotoxicologia , Monitoramento Ambiental , Chuva , Poluentes Químicos da Água , Monitoramento Ambiental/métodos , Animais , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Esgotos , Águas Residuárias/toxicidade , Chironomidae , Daphnia , Chlorella vulgaris/efeitos dos fármacos , Testes de Toxicidade
18.
Environ Sci Pollut Res Int ; 31(44): 55851-55894, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39251536

RESUMO

In recent times, increased geogenic and human-centric activities have caused significant heavy metal(loid) (HM) contamination of soil, adversely impacting environmental, plant, and human health. Phytoremediation is an evolving, cost-effective, environment-friendly, in situ technology that employs indigenous/exotic plant species as natural purifiers to remove toxic HM(s) from deteriorated ambient soil. Interestingly, the plant's rhizomicrobiome is pivotal in promoting overall plant nutrition, health, and phytoremediation. Certain secondary metabolites produced by plant growth-promoting rhizobacteria (PGPR) directly participate in HM bioremediation through chelation/mobilization/sequestration/bioadsorption/bioaccumulation, thus altering metal(loid) bioavailability for their uptake, accumulation, and translocation by plants. Moreover, the metallotolerance of the PGPR and the host plant is another critical factor for the successful phytoremediation of metal(loid)-polluted soil. Among the phytotechniques available for HM remediation, phytoextraction/phytoaccumulation (HM mobilization, uptake, and accumulation within the different plant tissues) and phytosequestration/phytostabilization (HM immobilization within the soil) have gained momentum in recent years. Natural metal(loid)-hyperaccumulating plants have the potential to assimilate increased levels of metal(loid)s, and several such species have already been identified as potential candidates for HM phytoremediation. Furthermore, the development of transgenic rhizobacterial and/or plant strains with enhanced environmental adaptability and metal(loid) uptake ability using genetic engineering might open new avenues in PGPR-assisted phytoremediation technologies. With the use of the Geographic Information System (GIS) for identifying metal(loid)-impacted lands and an appropriate combination of normal/transgenic (hyper)accumulator plant(s) and rhizobacterial inoculant(s), it is possible to develop efficient integrated phytobial remediation strategies in boosting the clean-up process over vast regions of HM-contaminated sites and eventually restore ecosystem health.


Assuntos
Biodegradação Ambiental , Metais Pesados , Poluentes do Solo , Metais Pesados/metabolismo , Poluentes do Solo/metabolismo , Desenvolvimento Vegetal , Plantas/metabolismo , Microbiologia do Solo
19.
bioRxiv ; 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39314371

RESUMO

Trace amine-associated receptor 1 (TAAR1) is known to negatively regulate dopamine (DA) release. The partial TAAR1 agonist RO5263397 promotes wakefulness and suppresses NREM and REM sleep in mice, rats, and non-human primates. We tested the hypothesis that the TAAR1-mediated effects on sleep/wake were due, at least in part, to DA release. Male C57BL6/J mice (n=8) were intraperitoneally administered the D1R antagonist SCH23390, the D2R antagonist eticlopride, a combination of D1R+D2R antagonists or saline at ZT5.5, followed 30 min later by RO5263397 or vehicle (10% DMSO in DI water) at ZT6 per os. EEG, EMG, subcutaneous temperature, and activity were recorded in each mouse across the 8 treatment conditions and sleep architecture was analyzed for 6 hours post-dosing. Consistent with our previous reports, RO5263397 increased wakefulness as well as the latency to NREM and REM sleep. D1, D2, and D1+D2 pretreatment reduced RO5263397-induced wakefulness during the first 1-2 hours after dosing, but only the D1+D2 combination attenuated the wake-promoting effect of RO5263397 from ZT6-8, mostly by increasing NREM sleep. Although D1+D2 antagonism blocked the wake-promoting effect of RO5263397, only the D1 antagonist significantly reduced the TAAR1-mediated increase in NREM latency. Neither the D1 nor the D2 antagonist affected TAAR1-mediated suppression of REM sleep. These results suggest that, whereas TAAR1 effects on wakefulness are mediated in part through the D2R, D1R activation plays a role in reversing the TAAR1-mediated increase in NREM sleep latency. By contrast, TAAR1-mediated suppression of REM sleep appears not to involve D1R or D2R mechanisms.

20.
Sci Total Environ ; 954: 176320, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39322077

RESUMO

Trace elements (TE) in living organisms can have detrimental health impacts depending on their concentration. As many TEs are obtained through diet, trophic niche changes associated with the impacts of anthropogenic activities and climate-change may influence exposure to top predators. The Australian fur seal (Arctocephalus pusillus doriferus; AUFS) represents the greatest resident, marine predator biomass in south-eastern Australia. With adult female foraging ranges limited to the continental shelf, their source of TEs is geographically restricted. Plasma, red blood cell and milk samples collected between 1998 and 2022 at Kanowna Island, were analysed for TEs (As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, Sn, V and Zn) using inductively-coupled plasma mass-spectrometry (ICP-MS). Plasma fatty-acid profiles and ocean climate variables were used to investigate trophic and environmental influences, respectively, on TE concentrations. Estimated whole blood concentrations in lactating females were comparable to levels reported in other marine mammals, except for Se and Mn. Correlations between adult tissues were negative for Mn and positive for As, Hg and Sn. Molar Se:Hg were high but within reported levels for pinnipeds. Element concentrations in pup plasma were greater than lactating females for Fe, Mn and Sn indicative of high transplacental transfer while doses of Se and As from milk exceeded tolerable effect levels for humans. Relationships with fatty-acid profiles suggest diet influenced concentrations of Cu, Hg, Mn, Sn, V and Zn in adult plasma. In addition, inter-annual variation in TE concentrations were influenced by broad-scale climate indices, including the Southern Annular Mode and the Southern Oscillation Index, and local conditions associated with the seasonally-active Bonney Upwelling. These findings indicate that TE concentrations in blood and milk of AUFS are and will continue to be affected by anticipated oceanographic changes, mediated by alterations in prey type availability, with potential impacts on the population's health.

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