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1.
Huan Jing Ke Xue ; 42(7): 3206-3214, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212646

RESUMO

The contents of heavy metals (Cd, Cu, Cr, As, Mn, Ni, Pb, and Zn) in sediments from 20 representative sections of the ancient town of Suzhou were analyzed to determine the pollution degree and potential ecological risk, and pollution sources were identified. The results showed that the average concentrations of Cd, Cu, Cr, As, Mn, Ni, Pb, and Zn in river sediments from the ancient town of Suzhou were 1.1, 142.6, 90.2, 17.2, 800.1, 63.3, 199.1, and 384.2 mg·kg-1, respectively, and the proportions of sampling points that exceeded the soil background value of Jiangsu Province were 100%, 100%, 65%, 95%, 70%, 100%, 95%, and 100%, respectively. The geo-accumulation index indicated that the pollution degree of heavy metals followed the order of Pb > Cd > Cu > Zn > Cr > Ni > As > Mn. In general, high Pb pollution, moderate Cd, Cu, Zn, and Cr pollution, slight Ni and As pollution, and no Mn pollution were observed. The potential ecological risk index for heavy metals was determined to follow the order of Cd > Pb > Cu > As > Ni > Zn > Cr > Mn. Generally, Cd, Pb, and Cu presented moderate potential ecological risk, and the others presented low potential ecological risk. The average concentration of heavy metals, geo-accumulation index, and potential ecological risk index of river sediments in the northern and southern of ancient town were all higher than that of Ganjiang River and Huancheng River, indicating that the control of heavy metals should focus on the inner part of the ancient town. According to correlation analysis and principal component analysis, Cd, Cu, Cr, As, Ni, Pb, and Zn might be derived from man-made factors such as fertilizer, road aging, tire wear, exhaust emissions and so on, which Mn was mainly derived from natural factors.


Assuntos
Metais Pesados , Poluentes Químicos da Água , China , Monitoramento Ambiental , Sedimentos Geológicos , Metais Pesados/análise , Medição de Risco , Rios , Poluentes Químicos da Água/análise
2.
Huan Jing Ke Xue ; 42(7): 3215-3222, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212647

RESUMO

In the present study, the spatio-temporal distribution characteristics of heavy metals (Cd, Hg, As, Pb, Cr, Cu, Ni, and Zn) in soil around 19 centralized drinking water sources in Wuhan were investigated. Single-factor and comprehensive pollution indexes were used to determine soil pollution levels. The potential ecological hazard index was employed to evaluate soil potential ecological risks. The correlation and cluster analysis were conducted to identify pollution sources. The results showed that higher concentrations of heavy metals were present in soil from centralized drinking water source located in core area than suburb area of Wuhan. The concentrations of heavy metals in soil from centralized drinking water sources near the Yangtze River were higher than that in the sites near the tributaries of the Yangtze River. The average single potential ecological risk index of Hg, As, Pb, Cr, Cu, Ni, and Zn were lower than 40, which suggests a slight potential ecological risk. The average single potential ecological risk index of Cd was 80-160, which indicates a high potential ecological risk. The average comprehensive potential ecological risk index of heavy metals in soil around centralized drinking water sources in Wuhan was 142.12, which corresponded to a slight potential ecological risk. The correlation analysis showed that the sources of Cu, Pb, and Cr were similar and came from transport. The sources of Ni, As, Cr, and Cu were similar and could be attributed to metallurgical industries. The sources of Zn, Hg, and Cr were similar and could be related to antiseptic and catalytic industries. The long-term monitoring of Wuhan Dijiao and Baishazhou waterworks indicated that the concentrations of heavy metals around centralized drinking water sources in Wuhan were markedly decreased after 2017 and that ecological risk may be further reduced in the future.


Assuntos
Água Potável , Metais Pesados , Poluentes do Solo , China , Monitoramento Ambiental , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise
3.
Huan Jing Ke Xue ; 42(7): 3304-3315, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212656

RESUMO

Urban surface runoff is an important non-point pollution source, and research on contamination characteristics of runoff is urgent for improving urban aquatic environment quality. Typical cities along the downstream Yangtze River, Wuxi and Nanjing, were selected in this study, and runoff samples from various underlying surfaces were collected to investigate contamination characteristics of heavy metals and dissolved organic matter (DOM). The results indicated that the concentration of heavy metals have exceed water quality standards in underlying surfaces partly, the decreasing order of metal contaminations was Zn > Cu > Pb > Sb > Cd. Contamination characteristics of surface runoff were found to exhibit significant differences, and arterial traffic exhibited the severe contamination of both heavy metals and DOM. Spectral characteristics indicated that the structure of DOM exhibited significant differences in various underlying surfaces, and DOM humification levels in Wuxi showed the following decreasing order:roof covering > sidewalk > parking area > grassy area > arterial traffic, aromaticity indexes exhibited order as:arterial traffic > grassy area > sidewalk > roof covering > parking area. Differential absorption spectroscopy (DAS) and FT-IR analyses indicated that DOM exhibited strong combination effects with cationic metal pollutants (Cu), which mainly occur with C=C structure and carboxylic and phenolic groups; DOM presented weak combination with anion metal pollutant (Sb), indicating that Sb likely exists as a free anion in runoff. The annual total loadings of metal contaminations in the study area were as follows:Zn > Cu > Pb > Sb > Cd. The loadings of Zn were 4.83 kg·a-1 and 3.21 kg·a-1 in Wuxi and Nanjing, respectively. Annual loadings of DOM reached 0.93 g·(m2·a)-1 and 8.72 g·(m2·a)-1. The results indicated that corresponding pollution reduction measures should be implemented for different underlying surfaces to reduce contaminant concentrations; our findings may provide essential information for improving the aquatic environment quality in downstream Yangtze River.


Assuntos
Metais Pesados , Poluentes Químicos da Água , China , Cidades , Monitoramento Ambiental , Metais Pesados/análise , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise
4.
Huan Jing Ke Xue ; 42(7): 3507-3517, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212677

RESUMO

In this study, we hypothesized that the distribution patterns of trace metal elements in montane regions would be controlled by the local climate, human activities, vegetation distribution and soil development. Hence, we selected nine forest sites among the elevation of 850 m to 2650 m on the windward (western slope) and leeward (eastern slope) slopes of Ailao Mountain in Yunnan Province of China to determine the typical heavy metal concentrations in forest surface soils, and their differences for distribution trends along with the increasing elevations, and the corresponding environmental factors. The results showed that surface soil Cd, Sb, As, Cr, and Pb had relatively higher concentrations and distinct enrichment factors both on eastern and western slopes. Specifically, the concentrations of Cd and Sb in surface soils of the eastern and western slopes and Pb on the western slope all had obvious altitude distribution trends, which showed their concentrations increased with the increasing elevation. In addition, we found the concentrations of Cd, Sb, As, and Cr in surface soils of the western slope were significantly higher than those of the eastern slope at the same altitude. The correlation analysis and principal component analysis further depicted that the elevation trends of Cd and Sb were mainly controlled by the strong combining effects from long-range atmospheric input and soil organic matter strong absorption, and there was an obvious "cold trapping" effect in high altitude areas. The distribution variations of As and Cr were mainly derived from the weathering difference of soil parent material, while the variations for Pb were controlled by the weathering of bedrock minerals. This study highlights the important role of combining effects from long-range atmospheric input, and from precipitation and vegetation (such as "cold trapping" effect, promoting canopy filtration, litterfall deposition and bedrock weathering) on the distribution trends of trace metals in remote alpine soils.


Assuntos
Metais Pesados , Poluentes do Solo , China , Monitoramento Ambiental , Florestas , Humanos , Metais Pesados/análise , Solo , Poluentes do Solo/análise
5.
Huan Jing Ke Xue ; 42(7): 3518-3526, 2021 Jul 08.
Artigo em Chinês | MEDLINE | ID: mdl-34212678

RESUMO

Research on the characteristics of environmental background values of soil can provide a scientific basis for setting regional standards for soils. To determine the characteristics of environmental background values and main influencing factors of heavy metals (Cr, Cu, Zn, Ni, Pb, Co, V, Cd, and Hg) in soils in Shenzhen, 500 topsoil samples (0-20 cm) were collected by decision unit multi increment sampling (DUMS) from 500 soil background sites in the whole city, including 405 latosolic red soil, 77 red soil, and 18 yellow soil samples. The results show that the concentrations of heavy metals in red soil are relatively low in general, and those of Cr, Ni, Co, and V in latosolic red soil and Cu, Zn, Hg, Pb, and Cd in yellow soil are higher. Compared with the environmental background values of soil in the Seventh Five-year Plan of China in 1980s, the concentrations of Cr, Cu, Zn, Ni, Co, and V in latosolic red soil, red soil, and yellow soil are lower, the concentrations of Cd and Hg are similar, and the concentration of Pb is higher. The spatial distribution patterns of the nine heavy metals are significantly different. Pb, Zn, and Co present an obvious zonal distribution pattern, while Cr, Cu, Ni, V, Cd, and Hg present a point-like distribution pattern. Moreover, the correlation analysis between heavy metal content and physicochemical properties of different soils showed that the correlation between heavy metal content and physicochemical properties of latosolic red soil was the most significant. Stepwise regression analysis was used to elucidate the relationship between heavy metal content in latosolic red soil, and physicochemical properties were quantified. The physicochemical properties affecting heavy metal content in latosolic red soil were found to be mechanical composition, pH, organic matter, and cation exchange capacity.


Assuntos
Metais Pesados , Poluentes do Solo , China , Cidades , Monitoramento Ambiental , Metais Pesados/análise , Medição de Risco , Solo , Poluentes do Solo/análise
6.
Environ Monit Assess ; 193(8): 461, 2021 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-34216277

RESUMO

This study evaluated the level of heavy metal pollution in soils within the vicinity of hot mix asphalt (HMA) plants and the health risk consequences of human exposure to the heavy metals. Soil samples collected from two asphalt plants during dry and rainy seasons were analyzed for Cr, Co, Cu, Ni, Mn, Cd, Pb, and Zn with atomic absorption spectrophotometer (AAS). Health risk indices were assessed as chronic daily intake (CDI), hazard quotient (HQ), hazard index (HI), and carcinogenic risk (CR) while the degree of pollution was assessed with geo-accumulation index (Igeo) and contamination factor (CF). The pollution assessment revealed that the soil samples were moderately to highly polluted with Cd. In both seasons, Zn and Mn, respectively, had the highest CDI values for ingestion, inhalation, and dermal route for both asphalt plants while Cd has the least CDI values for all the routes in both plants. The HQ and HI values for all the metals were less than 1.00E + 00 indicating no non-carcinogenic risk from exposure to any of the metals. Furthermore, the dermal route was found to be the least likely model for health risks associated with human exposure to soil heavy metals within the vicinity of the plants. The CR values for the metals were also within threshold value indicating non-significant cancer risk from exposure to the metals. Though no significant health risks were observed in the study, clean and efficient production of hot mix asphalt should be encouraged to minimize health risks and environmental pollution during production and usage.


Assuntos
Metais Pesados , Poluentes do Solo , China , Monitoramento Ambiental , Poluição Ambiental/análise , Humanos , Hidrocarbonetos , Metais Pesados/análise , Nigéria , Medição de Risco , Solo , Poluentes do Solo/análise
7.
Talanta ; 233: 122490, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34215111

RESUMO

In natural environments, Acid Volatile Sulfides (AVS) contained in anoxic waters or sediments, are composed of dissolved sulfides and neo-formed sulfides colloids or particles. Under acidic addition, AVS emit hydrogen sulfide gas and release the so-called simultaneously extracted metals (SEM). The measurement of AVS coupled with that of the SEM enables to evaluate the metal trapping capacity of sulfides in the environment. Because AVS are extremely reactive to oxidation, the most accurate methodology to quantify AVS and SEM requires to be able to process the samples extraction on-site, directly after sampling and avoiding oxygen exposure. However, most of available systems are based on glassware 'purge and trap' techniques developed for the laboratory and are not often adapted to field studies. In these systems, AVS extraction time can range from 30 min to 3 h with relative standard deviation from 7 to 44%. In this study, we developed a new 'purge and trap' system designed for both laboratory use and field AVS/SEM extractions. The system is optimized with a shortened extraction time, miniaturized, unbreakable, easy and reproducible to develop parallel extraction benches. Analytical yields, precision and stability have been improved, allowing to reduce the extraction time to 1 h with an absolute quantification limit of 0.12 µmol S(-II) with a relative standard deviation between 7 and 11% and under a complete extraction efficiency.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Monitoramento Ambiental , Sedimentos Geológicos , Laboratórios , Metais , Metais Pesados/análise , Sulfetos/análise , Volatilização , Poluentes Químicos da Água/análise
8.
Artigo em Inglês | MEDLINE | ID: mdl-34205068

RESUMO

Concentrations of potentially toxic elements (PTEs) (Al, As, Cd, Cr, Cu, Ni, Pb, and Zn) were measured in topsoil samples collected from parks in the cities of Salzburg (Austria), Thessaloniki (Greece), and Belgrade (Serbia) in order to assess the distribution of PTEs in the urban environment, discriminate natural (lithogenic) and anthropogenic contributions, identify possible sources of pollution, and compare levels of pollution between the cities. An assessment of the health risks caused by exposure to PTEs through different pathways was also conducted. The study revealed that, with the exception of Pb in Salzburg, levels of PTEs in the soils in polluted urban parks were higher than in unpolluted ones, but still lower than those recorded in other European soils. Results of sequential analyses showed that Al, Cr, and Ni were found in residual phases, proving their predominantly lithogenic origin and their low mobility. In contrast, the influence of anthropogenic factors on Cu, Pb, and Zn was evident. Site-dependent variations showed that the highest concentrations of As, Cu, Pb, and Zn of anthropogenic origin were recorded in Salzburg, while the highest levels of Al, Cr, and Ni of lithogenic origin were recorded in Belgrade and Thessaloniki, which reflects the specificity of the geological substrates. Results obtained for the health risk assessment showed that no human health risk was found for either children or adults.


Assuntos
Metais Pesados , Poluentes do Solo , Áustria , Criança , Cidades , Monitoramento Ambiental , Grécia , Humanos , Metais Pesados/análise , Metais Pesados/toxicidade , Medição de Risco , Sérvia , Solo , Poluentes do Solo/análise
9.
Environ Monit Assess ; 193(8): 482, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34241689

RESUMO

Determination of the water quality monitoring network (WQMN) is a vital stage for surveying ecosystem health. Studies have been done in determining the optimal number and location of sampling points, but seasonality of water quality, especially for heavy metals, has been rarely studied. For the first time, this study proposes a framework to determine the optimal location of sampling points to monitor lead (Pb). This study was conducted for the Karoun River, located in southwestern Iran. First, hydraulic characteristics of the river were simulated by implementing of MIKE11 software as well as water quality(variation of Pb concentration). Nash­Sutcliffe coefficient were 0.91 and 0.91 for discharge calibration and validation, respectively. Second, 16 potential sampling points were proposed using modified Sanders' approach considering seasonality. For a better accuracy in the WQMN layout and a more efficient site selection of sampling points, a 1-km buffer is stretched along the river for determining non-point source pollution sources and prioritizing candidate points. This leads to considering different land uses in the study area, while GIS software has been employed. Seasonal changes and land use have a significant impact on the location of optimal sampling points. The presented framework can be used to improve water quality and support watershed protection efforts.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental , Hidrodinâmica , Irã (Geográfico) , Metais Pesados/análise , Rios , Poluentes Químicos da Água/análise , Qualidade da Água
10.
Environ Monit Assess ; 193(8): 483, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34241745

RESUMO

This work investigated heavy metal and cyanide pollution in surface soils and edible plants around Yanzhuang gold tailings ponds in the region of Yanzhuang Village in Pinggu District, Beijing. Surface soil samples were collected from 33 sites around gold tailings ponds, and concentrations of seven heavy metals (i.e., Sb, As, Cd, Cu, Pb, Zn, and Hg) and cyanide were analyzed to determine their spatial distributions, pollution degrees, and sources. The potential ecological risks of As, Cd, Cu, Pb, Zn, and Hg were preliminarily assessed. The results showed that the mean cyanide, Sb, As, Cd, Cu, and Pb concentrations were higher than the standard values. The pollutant concentrations around the tailings ponds were high and decreased with increasing distance from the ponds. The single pollution index indicated that cyanide, As, and Cd were the main pollutants. The Nemerow pollution index revealed a large region and serious degree of heavy metal pollution in soils. The potential ecological risk level of the study area was moderate, with Cd and As posing the main risks. Multivariate statistical analysis suggested that the heavy metal and cyanide pollution present mainly derived from gold tailings, with agricultural pollution also had a certain effect. However, the 12 edible plants sampled were basically not polluted.


Assuntos
Poluentes Ambientais , Metais Pesados , Poluentes do Solo , Pequim , China , Monitoramento Ambiental , Ouro , Metais Pesados/análise , Lagoas , Medição de Risco , Solo , Poluentes do Solo/análise
11.
Molecules ; 26(11)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34205887

RESUMO

Increasing heavy metal pollution in the environment and the fact that pine needles are good bio-monitors for air pollutants was the reason to investigate their accumulation in pine needles in Vienna (Austria). Pinus nigra is widespread over the city, thus allowing the study of different parameters influencing metal accumulation. The sampling sites were chosen based on traffic volume (low, medium, high). Fresh shoots were collected alongside one-year-old needles once per week from May to August 2015. The needle samples were washed and dried prior to acidic microwave-assisted digestion followed by quantitative determination using spectrometric methods. The investigation was focused on the following elements: Ag, Al, As, B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, Pb, Se, Sr, U, V, and Zn. The one-year-old needles mainly contained higher contents of elements than fresh shoots; in many cases, the values differed statistically significantly. By correlating needle elemental contents with the sampling site, statistically significant differences were registered for the majority of the investigated elements. These differences originate from the local traffic situation, soil elemental levels, translocation processes, and not traffic-related sources. No general trend of metal accumulation from spring to summer was registered.


Assuntos
Metais Pesados/análise , Pinus/química , Oligoelementos/análise , Áustria , Monitoramento Ambiental , Especificidade de Órgãos , Brotos de Planta/química , Solo/química
12.
Molecules ; 26(11)2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34199536

RESUMO

Accumulation of heavy metals (HMs) by ornamental plants (OPs) from contaminated agriculture soils is a unique technique that can efficiently reduce the metal load in the food chain. Amaranthus tricolor L. has attractive characteristics acquiring a higher growth rate and large biomass when grown at heavy metal contaminated soils. Site-specific detailed information is not available on the use of A. tricolor plant in metal phytoremediation from the polluted sites. The study aimed to enhance the uptake of HMs (Pb, Zn, and Cu) via amending poultry litter extract (PLE), vinasse sugarcane (VSC), and humic acid (HA) as natural mobilized organic materials compared to ethylene diamine tetraacetic acid (EDTA), as a common mobilized chemical agent by A. tricolor plant. The studied soils collected from Helwan, El-Gabal El-Asfar (Cairo Governorate), Arab El-Madabeg (Assiut Governorate), Egypt, and study have been conducted under pot condition. Our results revealed all organic materials in all studied soils, except EDTA in EL-Gabal El-Asfar soil, significantly increased the dry weight of the A. tricolor plant compared to the control treatment. The uptake of Pb and Zn significantly (p > 0.05) increased due to applying all organic materials to the studied soils. HA application caused the highest uptake as shown in Pb concentration by more than 5 times in Helwan soil and EDTA by 65% in El-Gabal El-Asfar soil while VSC increased it by 110% in El-Madabeg soil. Also, an increase in Zn concentration due to EDTA application was 58, 42, and 56% for Helwan, El-Gabal El-Asfar, and El-Madabeg soil, respectively. In all studied soils, the application of organic materials increased the remediation factor (RF) than the control. El-Madabeg soil treated with vinasse sugarcane gave the highest RF values; 6.40, 3.26, and 4.02% for Pb, Zn, and Cu, respectively, than the control. Thus, we identified A. tricolor as a successful ornamental candidate that, along with organic mobilization amendments, most efficiently develop soil health, reduce metal toxicity, and recommend remediation of heavy metal-contaminated soils. Additionally, long-term application of organic mobilization amendments and continued growth of A. tricolor under field conditions could be recommended for future directions to confirm the results.


Assuntos
Amaranthus/crescimento & desenvolvimento , Metais Pesados/análise , Poluentes do Solo/análise , Amaranthus/metabolismo , Biodegradação Ambiental , Biomassa , Ácido Edético/química , Egito , Substâncias Húmicas/análise
13.
Microbiome ; 9(1): 156, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34229757

RESUMO

Manufacturing and resource industries are the key drivers for economic growth with a huge environmental cost (e.g. discharge of industrial effluents and post-mining substrates). Pollutants from waste streams, either organic or inorganic (e.g. heavy metals), are prone to interact with their physical environment that not only affects the ecosystem health but also the livelihood of local communities. Unlike organic pollutants, heavy metals or trace metals (e.g. chromium, mercury) are non-biodegradable, bioaccumulate through food-web interactions and are likely to have a long-term impact on ecosystem health. Microorganisms provide varied ecosystem services including climate regulation, purification of groundwater, rehabilitation of contaminated sites by detoxifying pollutants. Recent studies have highlighted the potential of methanotrophs, a group of bacteria that can use methane as a sole carbon and energy source, to transform toxic metal (loids) such as chromium, mercury and selenium. In this review, we synthesise recent advances in the role of essential metals (e.g. copper) for methanotroph activity, uptake mechanisms alongside their potential to transform toxic heavy metal (loids). Case studies are presented on chromium, selenium and mercury pollution from the tanneries, coal burning and artisanal gold mining, respectively, which are particular problems in the developing economy that we propose may be suitable for remediation by methanotrophs. Video Abstract.


Assuntos
Mercúrio , Metais Pesados , Cromo/análise , Ecossistema , Poluição Ambiental , Metais Pesados/análise
14.
Environ Pollut ; 284: 117533, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34261227

RESUMO

The Pearl River Estuary (PRE) is the largest estuary in southern China and under high metal stress. In the present study, we employed an integrated method of transcriptomics and proteomics to investigate the ecotoxicological effects of trace metals on the Hong Kong oyster Crassostrea hongkongensis. Three oyster populations with distinct spatial distributions of metals were sampled, including the Control (Station QA, the lowest metal levels), the High Cd (Station JZ, the highest Cd), and the High Zn-Cu-Cr-Ni (Station LFS, with the highest levels of zinc, copper, chromium, and nickel). Dominant metals in oysters were differentiated by principal component analysis (PCA), and theirgene and protein profiles were studied using RNA-seq and iTRAQ techniques. Of the 2250 proteins identified at both protein and RNA levels, 70 proteins exhibited differential expressions in response to metal stress in oysters from the two contaminated stations. There were 8 proteins altered at both stations, with the potential effects on mitochondria and endoplasmic reticulum by Ag. The genotoxicity, including impaired DNA replication and transcription, was specifically observed in the High Cd oysters with the dominating influence of Cd. The structural components (cytoskeleton and chromosome-associated proteins) were impaired by the over-accumulated Cu, Zn, Cr, and Ni at Station LFS. However, enhanced tRNA biogenesis and exosome activity might help the oysters to alleviate the toxicities resulting from their exposure to these metals. Our study provided comprehensive information on the molecular changes in oysters at both protein and RNA levels in responding to multi-levels of trace metal stress.


Assuntos
Crassostrea , Metais Pesados , Poluentes Químicos da Água , Animais , China , Monitoramento Ambiental , Estuários , Hong Kong , Metais Pesados/análise , Metais Pesados/toxicidade , Proteômica , Transcriptoma , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
15.
Environ Monit Assess ; 193(8): 465, 2021 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-34218335

RESUMO

This study was conducted on the Danube River locality Visnjica, exposed to the discharge of the largest wastewater collector in Serbia's capital, Belgrade. Concentrations of metals and metalloids (Al, Fe, Cr, As, Sr, Mn, Cd, Zn, Mo, Cu, Li, Ni, B, Co, Pb, and Ba) and histopathological alterations were investigated in different tissues of common bream during one representative month of each season in 2014. This is the first study in which these two biomarkers were assessed parallelly in common bream. The highest concentrations of examined elements were noticed in gills and the lowest in muscle. Statistically significant differences in element concentrations between different seasons were noticed only in gills for Al, Cu, and Fe. Concentrations of As and Pb in fish muscle were below the maximum acceptable concentrations (MAC). The histopathological index (HI) of the liver showed higher values in comparison to the HI of the gills. Histopathological index of the gills had a significantly higher score in November in comparison to August. The liver HI had the highest score in April, and the lowest in August, while the total histopathological index had the highest score in November, and the lowest in August, both without significant differences between the months. This study endorses gills and liver as reliable organs for studying accumulation and histopathology as biomarkers of environmental changes. A faster reaction of the gills was confirmed since seasonal variations of both biomarkers were observed in this organ. Common bream proved as a good indicator of the state of organisms in polluted environments.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Animais , Biomarcadores , Monitoramento Ambiental , Brânquias/química , Metais Pesados/análise , Rios , Sérvia , Águas Residuárias , Poluentes Químicos da Água/análise
16.
Environ Monit Assess ; 193(8): 469, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34226963

RESUMO

Recently, reservoirs in southern China are witnessing incidents involving black water, which are harmful to the aquatic ecosystem. This study unravels the cause of the black water events by studying the occurrence and the ecological risks of contaminants (Pb, Cu, Cd, Zn, Ni, TFe, Mn, S, P, and DOC) in sediments of Tianbao reservoir. Due to the significantly high concentration of TFe, Mn, and P in the sediments, the study further used the thin film diffusion gradient (DGT) technology and high-resolution dialysis method to investigate the movement of Fe2+, Mn2+, S2-, and reactive P within the sediments. The ecological risk assessment (threshold effect level and probable effect level) showed that the sediments had a low concentration of Pb, Cu, Cd, Zn, and Ni. High organic matter from the Eucalyptus plantation surrounding the reservoir, as well as the intense thermal stratification of the reservoir, caused the hypolimnion to be hypoxic (DO < 2 mg/L). The diffusion fluxes at the water-sediment boundary (WSB) demonstrated a significant movement of Fe2+, Mn2+, and PO43- from the sediments into the overlying water, while the movement of S2- was in both directions due to hypoxia. A high correlation Fe-DOC (r = 0.9), Fe-S (r = 0.8), and Mn-S (r = 0.7) and the redox interaction of Fe2+, Mn2+, S2-, P, and DOC at the hypoxic WSB caused the production of black substances in the hypolimnion contributing to the so-called black water reservoir.


Assuntos
Metais Pesados , Poluentes Químicos da Água , China , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos , Metais Pesados/análise , Diálise Renal , Poluentes Químicos da Água/análise
17.
J Environ Sci (China) ; 106: 1-14, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34210425

RESUMO

The synthesis of biological silicon nano-particles (Bio-Si-NPs) is an eco-friendly and low-cost method. There is no study focusing on the effect of Bio-Si-NPs on the plants grown on saline soil contaminated with heavy metals. In this study, an attempt was made to synthesis Bio-Si-NPs using potassium silica florid substrate, and the identified Aspergillus tubingensis AM11 isolate that separated from distribution systems of the potable water. A two-year field trial was conducted to compare the protective effects of Bio-Si-NPs (2.5 and 5.0 mmol/L) and potassium silicate (10 mmol/L) as a foliar spray on the antioxidant defense system, physio-biochemical components, and the contaminants contents of Phaseolus vulgaris L. grown on saline soil contaminated with heavy metals. Our findings showed that all treatments of Bio-Si-NPs and potassium silicate significantly improved plant growth and production, chlorophylls, carotenoids, transpiration rate, net photosynthetic rate, stomatal conductance, membrane stability index, relative water content, free proline, total soluble sugars, N, P, K, Ca2+, K+/Na+, and the activities of peroxidase, catalase, ascorbic peroxidase and superoxide oxide dismutase. Application of Bio-Si-NPs and potassium silicate significantly decreased electrolyte leakage, malondialdehyde, H2O2, O2•-, Na+, Pb, Cd, and Ni in leaves and pods of Phaseolus vulgaris L. compared to control. Bio-Si-NPs were more effective compared to potassium silicate. Application of Bio-Si-NPs at the rate of 5 mmol/L was the recommended treatment to enhance the performance and reduce heavy metals content on plants grown on contaminated saline soils.


Assuntos
Metais Pesados , Nanopartículas , Phaseolus , Poluentes do Solo , Antioxidantes , Aspergillus , Metais Pesados/análise , Silício , Solo , Poluentes do Solo/análise
18.
Front Public Health ; 9: 620700, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34211949

RESUMO

Many people in the world lack safe basic drinking water sources and rely on untreated water source. Packaged water can be considered as an alternative to other water sources if measures are put in place to ensure its safety for consumption. This study aimed to assess the bacteriological quality and heavy metal analysis of packaged water produced in Lusaka, Zambia and associated quality control measures. A cross-sectional study was conducted in May 2019 where 18 brands of packaged water were analyzed for total and fecal coliforms as well as concentrations of Lead, Chromium, and Cadmium. The study found that 33.5% of the packaged water produced in Lusaka did not comply with the standard for drinking water on bacteriological quality. We also found that the concentrations for Lead were <0.01 mg/l in all the 17 samples, thus compliant to WHO/ZABS standards. Concentrations of Chromium were between 0.002 and 0.62 mg/l and compliance to the standard was 11.8%. Concentrations for Cadmium were between 0.009 and 0.2 mg/l against the acceptable concentration of <0.003 mg/l. Most brands of the packaged water did not conform to the standards for drinking water.


Assuntos
Metais Pesados , Água , Estudos Transversais , Humanos , Metais Pesados/análise , Controle de Qualidade , Água/análise , Microbiologia da Água , Zâmbia
19.
Braz J Biol ; 82: e246979, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34133578

RESUMO

The influence of pharmaceutical residues and heavy metals on living organisms has received global attention. The present study assessed the interactive effect of antibiotic residues and heavy metals in soil, as contaminated food with cadmium (Cd) and oxytetracycline (OTC) on the isopod Porcellio leavis. It was fed on fresh plant leaves contaminated with different concentrations of cadmium, Cd+OTC1000 ppm, Cd+OTC2000 ppm and Cd+OTC3000 ppm for 4 weeks. The changes in the feeding patterns, protein, lipid peroxidation (LPO), catalase activity (CAT), and total free amino acids (TFAA) were recorded. There were significant differences in the obtained results where Cd reduced the egestion ratio (ER) however, OTC enhanced this ratio. Biochemical analysis illustrated that combination between OTC and Cd inhibits the toxic effects of Cd at low concentration (1000 ppm), while at high concentration (3000 ppm) raise the toxicity. Detailed studies are required for further understanding of the interaction between OTC and heavy metals, and also its impact on soil animals and for improving soil risk evaluation.


Assuntos
Isópodes , Metais Pesados , Oxitetraciclina , Poluentes do Solo , Animais , Cádmio/toxicidade , Metais Pesados/análise , Oxitetraciclina/toxicidade , Solo , Poluentes do Solo/toxicidade
20.
Chemosphere ; 279: 130632, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34134423

RESUMO

The accumulated bauxite mine soil had an acidic pH of 5.52 ± 0.12 and more heavy metals such as Cr, Cd, Zn, and Pb, which can cause severe soil and water pollution to the nearby farmlands and water reservoirs. Hence, the work was designed to find the possibility of reclamation of bauxite mine soil through Crotalaria juncea with the amalgamation of native metal degrading bacterial isolates. Out of 15 bacterial cultures, only 2 isolates (B3 and B14) showed excellent metal tolerance (for up to 750 mg L-1), solubilizing (15.27-38.7 mg kg-1) (including phosphate: 47.4 ± 1.79%), and degrading potential (22.8 ± 0.89 to 31.5 ± 1.6%) than the others. These B3 and B14 isolates were recognized as B. borstelensis UTM105 (1432 bp) and B. borstelensis AK2 (1494 bp) through molecular characterization. These isolates have produced a metal stress response protein (205-43 KDa molecular weight protein) during metal stress conditions. The phytoremediation competence of C. juncea under the influence of these bacterial isolates was assessed with various treatment (I-IV) schemes. The treatment IV (C. juncea with two bacterial isolates) showed substantial physiological and biochemical results compared with the control and the other treatments. The phytoremediation competence of C. juncea was also effective in treatment IV than the others. It reduced and extracted a reasonable quantity of metals from the bauxite mine soil. The intact results accomplished that these native metals tolerant, solubilizing, and degrading bacterial isolates, could be used as optimistic bacterial candidates in combination with C. juncea for the effective reclamation of metal enriched bauxite mine soil.


Assuntos
Crotalaria , Metais Pesados , Poluentes do Solo , Óxido de Alumínio , Bactérias , Biodegradação Ambiental , Metais Pesados/análise , Mostardeira , Solo , Poluentes do Solo/análise , Instalações de Eliminação de Resíduos
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