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Biological toxicity testing plays an essential role in identifying the possible negative effects induced by substances such as organic pollutants or heavy metals. As an alternative to conventional methods of toxicity detection, paper-based analytical device (PAD) offers advantages in terms of convenience, quick results, environmental friendliness, and cost-effectiveness. However, detecting the toxicity of both organic pollutants and heavy metals is challenging for a PAD. Here, we show the evaluation of biotoxicity testing for chlorophenols (pentachlorophenol, 2,4-dichlorophenol, and 4-chlorophenol) and heavy metals (Cu2+, Zn2+, and Pb2+) by a resazurin-integrated PAD. The results were achieved by observing the colourimetric response of bacteria (Enterococcus faecalis and Escherichia coli) to resazurin reduction on the PAD. The toxicity responses of E. faecalis-PAD and E. coli-PAD to chlorophenols and heavy metals can be read within 10 min and 40 min, respectively. Compared to the traditional growth inhibition experiments for toxicity measuring which takes at least 3 h, the resazurin-integrated PAD can recognize toxicity differences between studied chlorophenols and between studied heavy metals within 40 min.

Three grades of pectin xanthates (PX1, PX2, and PX3) have been prepared by the reaction of pectin with carbon disulfide (CS2) in an alkaline medium using NaOH, via the xanthation process. The percentage yield of prepared pectin xanthates has been found to be 87.06%, 90.38%, and 93.80% for PX1, PX2, and PX3, respectively. Prepared pectin xanthates and raw pectin were utilized for heavy metals (Cu(II) and Ni(II)) and lignin enriched paper industry wastewater (LEPIW) treatment. The removal percentage of pectin, PX1, P X2, and PX3 for Cu removal at optimum condition (adsorbent dose: 5.14 g/L, pH: 5 for Cu and 7 for Ni, optimum temperature: 50°C and time: 80 min for Cu(II) and 100 min for Ni(II)) has been found as 85%, 92.33%, 93.5%, and 94.66% and 76.66%, 89.44%, 91.66%, and 93.33%, respectively, for Ni removal. The LEPIW treatment efficacy for pectin, PX1, PX2, and PX3 has been found to be 54%, 77%, 83%, and 86% for the initial COD: 2000 mg/L, pH: 7, optimum temperature: 40°C in 105 min operation time. Adsorption isotherm studies suggest that Langmuir isotherm is most appropriate which indicates adsorption follows chemisorption. The adsorption capacities of PX1, PX2, and PX3 are found as 309.59, 352.11, and 380.22 mg/g for Cu(II) and 299.40, 315.45, and 328.94 mg/g and for Ni(II), respectively, which is very high in comparison with many other recent literature studies. [ABSTRACT FROM AUTHOR]

The performance of an asphalt mixture does not only rely on its engineering properties. Yet, the service characteristics of an asphalt mixture do play an important role on the durability of pavements. This study was conducted to evaluate the effect of different aggregate types (granite and limestone) and the incorporation of recycled paper mill sludge (RPMS) on mixtures behaviour in terms of workability and compaction energy index (CEI). The effect of RPMS incorporation on the leaching potential was also assessed. A test was evaluated through the toxicity characteristics leaching procedure (TCLP) to identify the leaching behaviour of heavy metals with a possibility to contaminate the nearby water sources. Next, a surface morphological analysis was also conducted through the Scanning Electron Microscopy (SEM) to assess the relationship of fillers addition to the optimum binder content and water absorption. In this study, RPMS was used at rates of 0.5% and 1%. Based on the TCLP's results, the leaching potential of RPMS incorporated mixture was addressed and proven to be less than the standardised requirements. The addition of different percentages of RPMS into limestone and granite asphalt mixtures had resulted in the increment of optimum binder content; however, still lower than control samples. Whereas their small increment in the combined water absorption percentage are relatively same to the control samples. The workability indices of asphalt mixtures peaked upon the usage of 0.5% RPMS but slightly reduced at 1% RPMS but nevertheless remained higher than the control specimen. This is due to the ability of RPMS reduce the surface tension, hence enabling less energy for compaction. The 0.5% RPMS addition was found to be the optimal content required to obtain a better service performance of asphalt mixture during mixing and compaction processes. [ABSTRACT FROM AUTHOR]

Abstract Patterned paper sensors such as letter- and barcode-shaped sensors have become a subject of growing interest due to the potential in information embedding and data interpretation, which brings a requirement on easily fabricating these paper-based analytical devices. The answer, in part, may lie in the influence of paper structure on the performance of paper-based analytical devices. After investigating the effect of physical properties of paper on precipitation and non-precipitation assays for detecting Fe(II), here we propose a simple and promising approach for barrier-free paper patterning. Without building hydrophobic boundaries, the precipitates of sensing reactions on low-bulk and medium-thick paper substrates allow patterned signal readout directly. As a proof of concept, barrier-free patterned paper sensors for detecting heavy metals were fabricated, with detection limits of 0.25 ppm for Fe(II), 0.4 ppm for Ni(II), and 0.5 ppm for Cu(II). Our work provides a valuable perspective on fabrication of patterned paper sensors. Graphical abstract fx1 Highlights • Skipping the hydrophobic treatment in fabrication of patterned paper sensors. • Providing a versatile platform for facile preparation of patterned paper sensors. • Low-bulk and medium-thick paper substrate holds the key to barrier-free fabrication. [ABSTRACT FROM AUTHOR]

Pollutants emerging from the effluents of paper mills eventually destroy the environment of our ecosystem. To find a proper solution of it, a cost-effective and environmentally benign technique is proposed here to remediate contaminants present in the effluent of paper mill in a sequential steps using advanced oxidation processes including Fenton reaction (FO) (Fe(II)/H2O2), modified Fenton oxidation (MFO) (Fe(II)/Zn(II)/H2O2) and biological flocculation process. A comparison and compilation among these techniques were carried out on the basis of the percentage removal of chemical oxygen demand (COD) as well as the observed degradation pattern in gas chromatography–mass spectrometry. Results revealed that MFO could remove ≥ 90% of COD at ~ 90 min, whereas FO could eliminate ≥ 80% COD at ~ 120 min. Further, the bioflocculation technique was found to reduce the heavy metal contents such as Fe, Mn, Zn, Co, Cd and Pb by ≥ 60%. In the sequential treatment process, lignin, phenolic and colour contents were also found to be reduced by ~ 84% ~ 97% and ~ 96%, respectively. Again, the bioassay tests were performed to verify the toxicity reduction in the industrial effluent after the application of the sequential treatment process. This study demonstrates that the sequential treatment technique could be an effective alternative for the treatment of paper mill effluent. [ABSTRACT FROM AUTHOR]

Precipitation of heavy metals in synthetic and actual wastewater with lime mud (solid waste generated from the pulp and paper production process) was experimented using Jar-tests. Separate synthetic wastewater samples were prepared for each of the following heavy metals: lead (1,433.7 mgPb2+/L), chromium (506.7 mgCr3+/L), cadmium (1,095 mgCd2+/L) and mercury (9.37 mgHg2+/L). The actual wastewater was tanning wastewater containing 74.49 mgCr3+/L and COD wastewater containing 683 mgHg2+/L. Adjustments of pH in the acidic range, pH 2-7, were made for each type of synthetic wastewater except for the Hg synthetic wastewater. The optimum conditions obtained from the tests of the synthetic wastewater were used for theactual wastewater samples. Precipitation of heavy metals with lime mud was effective as indicated by the removal efficiency as high as 90% up for Pb, Cd and Hg and 100% for Cr. However, the removal efficiency for the Hg-COD wastewater was only 67%. The precipitating pH was in the range of 10 up, which is the common pH range for metal carbonate precipitation. The optimum dosage of lime mud for Pb, Cr, Cd and Hg synthetic wastewater was 0.4-1.0 g/L, 2.0-4.0 g/L, 1.6-2.0g/L and 0.8 g/L, respectively. While the optimum dosage of lime mud for precipitating chromium in tanning wastewater was 3.8 g/L and 3.6 g/L for precipitating mercury in COD wastewater.

The JK Paper industry located at Rayagada discharges biologically untreated effluent more than the permissible limit prescribed by Pollution Control Board, Odisha in to the environment. The industry is seriously polluting the surrounding aquatic and terrestrial environment. No detailed intensive study was carried out by previous workers on this industry earlier. The present study aims at finding out the impact of effluent on the flora at the contaminated site. The chemically treated effluent (TE) contained significant amount of mercury and cadmium. The TE has high BOD, COD, dissolved solids and suspended solids when compared to normal river water at the site of discharge. The TE deteriorated the natural water bodies changing the physico-chemical properties of natural river water. After meeting the river water the TE was diluted after 1 km distance from the meeting point of the river. Crop plants collected from the contaminated site showed higher level of residual Hg and Cd and significant depletion in pigment was observed. Plants collected from both the sides of the treated effluent canal showed significant amount residue mercury and cadmium in the plant leaves. The plants exposed to the TE, showed variation in chlorophyll and Phaeophytin pigment content when compared to their respective control values in all terrestrial plants collected from the contaminated site. In some plant leaves little increment in the pigment level was noted but the values were not significant. The changes observed in the plant pigment might be due to heavy metal accumulation. The presence of residual Hg and Cd in crop plants and plant leaves grazed by grazing animals after absorption, accumulation and enrichment may lead to a possible biological magnification, warrants attention. Proper biological treatment, treatment of effluent by modern methods and removal of heavy metals from the effluent before discharge by the industry is suggested. • Biological treatment of the effluent was not carried out by the industry & chemicals present in the effluent were significantly high.. • The water quality of the river water deteriorated due to the discharge of effluent of the paper mill. • Plants collected from the contaminated site showed significant accumulation of cadmium and mercury in leaf tissues • Significant depletion in pigment content of exposed plant leaves was noticed. • Depletion in plant pigment was due to accumulation of cadmium and mercury in plant tissues absorbed from the effluent. [ABSTRACT FROM AUTHOR]

This paper presents a green manufacturing-recycling network design approach for multi-echelon electronic assembly process under a complex product mix scenario which incorporates trade-off between economic cost and heavy metal pollutants. The approach is developed by formulating the green manufacturing-recycling network into a closed-loop logistics bi-objective optimisation model, in order to alleviate negative environmental influence by applying proper cleaner production technologies. The environmental influence is quantified by pollution equivalent numbers which are integrated in the model. Moreover, the volume of the heavy metal pollutants is optimised by selecting the cleaner production level and thus is jointly coordinated with the operation cost. To solve the bi-objective optimisation model, an enhanced global criterion approach is presented to improve the effectiveness on dealing with non-convexity of the Pareto-optimal frontier with computational efficient solutions. The proposed model is implemented on a case study to verify its flexibility to handle the closed-loop manufacturing-recycling network design of different sizes, as well as to obtain trade-off between operation cost and environmental influence by the heavy metal pollutants under various scenarios. [ABSTRACT FROM AUTHOR]

A graphene paper-based flexible solid-contact ion-selective electrode (SC-ISE) was developed to detect lead ion sensitively. Graphene paper obtained via a simple vacuum filtration method was used as the electrode substrate for direct coating of an ion-selective membrane. The Nernstian slope of the prepared paper-based potentiometric sensor toward lead ion detection was demonstrated as 29.4 mV per decade. A detection limit as low as 2.5 x 10-7 mol L-1 was achieved. Reversed chronopotentiometry and water layer test revealed that the graphene paper-based SC-ISE possessed excellent potential stability because of the hydrophobicity of graphene paper. Furthermore, reliable data were obtained from the detection of lead ion levels in real water samples using the graphene paper-based potentiometric sensor, which shows great potential in practical application. [ABSTRACT FROM AUTHOR]

Abstract: Through sampling reed in Shuangtai estuary wetland in April, 2009 and simulation test in Shenyang Agricultural University, we analyze the removal efficiency of Cu, Zn, Pb and Cd during different growth period of reed and distribution of them in various parts of reed. The results show that the removal efficiency is best in jointing stage, the removal of Pb largest with 21% increase and 30% in sprout and exhibition leaf period, the removal of Zn largest with 53% and 29% increase in jointing stage and the maturity period, the removal of Cd largest with 40% increase in the different growing season. The absorption amount of Cu, Zn, Pb and Cd in roots of reed reaches maximum during the growth, followed by in stems and in leaves. Absorptive capacity in the whole plant for Cu, Zn, Pb and Cd exists extremely significant difference (p <0.01). The order is Pb>Zn>Cu>Cd. The absorption in root is higher than in stems and in leaves (p <0.05), but Zn and Cd absorption amount has no significant differences in stems and leaves (p >0.05). [Copyright &y& Elsevier]

[Display omitted] • GQD-DDT and GQD-MPA was synthesized using novel hydrothermal protocol. • GQD-DDT and GQD-MPA was used for the identification of cations using colorimetric and spectrophotometric assay. • GQD-DDT and GQD-MPA have well activity for ion sensing in aqueous solution. This study describes the synthesis of various types of thiolated-graphene quantum dots (GQDs) for the simultaneous multi-sensing of heavy metal ions using one-droplet microfluidic paper-based analytical devices (OD- µ PADs). For the first time, functionalized GQDs were synthesized and stabilized on the surface of hydrophobic fiber-glass with simple manufacturing and assembly strategy towards colorimetric chemosensing of ions including iron, copper, cobalt, mercury, chrome, manganese, and nickel. For this purpose, GQDs are functionalized by various organic species including cysteamine, decanethiol, and mercaptopropionic acid (MPA) towards specific electrostatic interaction with metal ions of Fe (II), Cu (II), Co(II), Hg (II), Mn (II), and Ni (II). Therefore, an innovative GQDs-based miniaturized chemo-system was proposed for the environmental analysis. Additionally, the results were confirmed using fluorescence spectrometry as an optical detection method. Finally, this simple and efficient colorimetric platform was used for facile metal ions detection in human urine models, and environmental fluids, which can provide a commercial device for sensing contaminants by non-professional users in biomedical/environmental mixture. As an economical technique, this platform presents a "mix-and-sense" system without dye (as a side substance) or chemical treatments. The low instrumental requirements, the color uniformity, and the disposability of OD- μ PADs approve the commercial application of the engineered ion-chemosensor. [ABSTRACT FROM AUTHOR]

Biological toxicity testing plays an essential role in identifying the possible negative effects induced by substances such as organic pollutants or heavy metals. As an alternative to conventional methods of toxicity detection, paper-based analytical device (PAD) offers advantages in terms of convenience, quick results, environmental friendliness, and cost-effectiveness. However, detecting the toxicity of both organic pollutants and heavy metals is challenging for a PAD. Here, we show the evaluation of biotoxicity testing for chlorophenols (pentachlorophenol, 2,4-dichlorophenol, and 4-chlorophenol) and heavy metals (Cu2+, Zn2+, and Pb2+) by a resazurin-integrated PAD. The results were achieved by observing the colourimetric response of bacteria (Enterococcus faecalis and Escherichia coli) to resazurin reduction on the PAD. The toxicity responses of E. faecalis-PAD and E. coli-PAD to chlorophenols and heavy metals can be read within 10 min and 40 min, respectively. Compared to the traditional growth inhibition experiments for toxicity measuring which takes at least 3 h, the resazurin-integrated PAD can recognize toxicity differences between studied chlorophenols and between studied heavy metals within 40 min. [ABSTRACT FROM AUTHOR]

Highlights: [•] Disposal of toxic sludge containing heavy metals poses an environmental risk. [•] Pyrolysis of sludge was performed to explore the potential of biochar for reuse. [•] The effect of pyrolysis temperature on partitioning of heavy metals was studied. [•] Fractionation and bioavailability of heavy metals in sludge and biochar was analyzed. [•] The leachability and ecotoxicity of heavy metals in biochar were determined. [Copyright &y& Elsevier]

The results of physico-chemical analysis of pulp and paper mill effluent sedimented sludge revealed the presence of heavy metals (mg l −1 ) Fe (67.53), Zn (13.90), Cu (2.15), Cr (2.30), Cd (0.255), Mn (11.0), Ni (3.30), and Pb (1.05) along with persistent chlorolignin. The major persistent organic pollutants detected by GC–MS were ethane, 1,1-diethoxy; tetradecanoic acid; furane 2,5-dimethyl; n -hexadecanoic acid; nonacosane, trimethylenebis-1,3-dioxolane; 1,3-dioxolane, 2-(phynylmethyl). Twelve representative native plants were noted based on their population number growing on pulp and paper sludge and evaluated for their phytoextraction potential of heavy metals. The result revealed that Triticum aestivum was found as root accumulator for all metals except Cu. Similarly, the Brassica campestris accumulated all metals maximum in root except Ni, Fe and Pb. While, Eclipta alba accumulated majority of metals in their shoot and leaves, But Solanum nigrum, Rumex dentatus accumulated metals in root and shoot both. Rananculus scleratus accumulated all the tested metals in their aerial parts except Cd and Pb. Cammelina benghalensis accumulated metals in root except Cd, Pd. Similarly the Phragmites cummunis and Ricinus cummunis accumulated majority of metals in their shoot and leaves. It was also noted that several evaluated plant showed bioconcentration factor (BCF) greater than one for accumulated metals i.e. Pb in T . aestivum (1.285), C . benghalensis (5.142), Cannabis sativa (3.466), P . cummunis (7.180), R . cummunis (66.80) was also noted. Furthermore, greater than one translocation factor (TF) for all these plants showed strong evidence for phytoextraction and in situ remediation potential of these plants. The overall order of phytoextraction potential of native wetland plants were C . sativa > P . cummunis > C . benghalensis > T . aestivum > B . campestris > E . alba . [ABSTRACT FROM AUTHOR]

Abstract: Metal pollution of soils is a great environmental problem. The major risks due to metal pollution of soil consist of leaching to groundwater and potential toxicity to plants and/or animals. The objective of this study is to evaluate by means of chemical and ecotoxicological approach the effects of paper mill sludge addition on the mobile metal fraction of polluted metal soils. The study was carried out on acidic soil derived from mining activities and thus polluted with heavy metals, and on two paper mill sludges having different chemical features. The results obtained by leaching experiments showed that the addition of a paper mill sludge, consisting mainly of carbonates, silicates and organic matter, to a heavy-metal polluted soil produces a decrease of available metal forms. The carbonate content seems to play a key role in the chemical stabilisation of metals and consequently in a decrease of toxicity of soil. The leached solutions have a non-toxic effect. The mild remediation by addition of sludge has moreover a lasting effect. [Copyright &y& Elsevier]

Heavy metal contamination of soil poses risks and hazards to environment and human being. Many amendments were used to remediate the contaminated soil. In this report, paper sludge was used to reduce the bioavailability of Pb in soil, and the remediation mechanism was studied by investigating the redistribution of Pb speciation after paper sludge addition. In pot experiments, significantly increased weights of shoots (from 1.6 to 3.3 mg per plant) and roots (from 0.7 to 0.8 mg per plant), as well as significantly decreased Pb content in shoots (from 153.8 to 24.4 mg kg−1) and roots (from 467.1 to 38.0 mg kg−1) of rape were observed after paper sludge was added. The addition of paper sludge resulted in redistribution of Pb from the liable fractions (carbonate-bound Pb from 58.3 to 3.7%) to the Fe–Mn oxide-bound fraction (from 29.2 to 74.9%). Paper sludge addition increased the content of organic matters and pH of soil, and induced Pb redistribution, which ultimately inhibited Pb uptake and improved plant growth. [ABSTRACT FROM AUTHOR]

[Display omitted] • A three-electrode system for cadmium detection with paper-based channels. • Detection areas and channels were created by forming a hydrophobic barrier on a paper using the wax. • Usage of 5 wt/wt% antimony precursor the carbon working electrode increased the sensitivity by 2.18 times. • The usage of a PET film decreased the price of the electrode, thereby rendering it suitable for disposable sensors. This paper describes the development of a heavy metal sensor with point-of-care detection for heavy metal detection based on paper channel. A heavy metal detection sensor using a three-electrode system was fabricated on the surface of PET by screen printing. The working electrode is made of carbon paste containing antimony precursors, the reference electrode is made of Ag/AgCl paste, and the auxiliary electrode is made of carbon paste. The fabricated three electrodes were designed to deliver target substance through a paper-based channel to allow very easy point-of-care detection. When measuring cadmium, the fabricated three electrodes showed the highest sensitivity when the antimony precursor concentration was 5 wt/wt%, which was about 2.18 times higher than that of the carbon paste electrode. The fabricated heavy metal sensor had a cadmium detection range of 20–2000 μg/L and a linear coefficient (R2) of 0.988 in the detection range of 20–500 μg/L. The developed paper channel-based heavy metal sensor can be fabricated at a very low cost and is expected to be applicable to other heavy metal detection applications. [ABSTRACT FROM AUTHOR]

Heavy metal pollution has shown great threat to the environment and public health worldwide. Current methods for the detection of heavy metals require expensive instrumentation and laborious operation, which can only be accomplished in centralized laboratories. Various microfluidic paper-based analytical devices have been developed recently as simple, cheap and disposable alternatives to conventional ones for on-site detection of heavy metals. In this review, we first summarize current development of paper-based analytical devices and discuss the selection of paper substrates, methods of device fabrication, and relevant theories in these devices. We then compare and categorize recent reports on detection of heavy metals using paper-based microfluidic devices on the basis of various detection mechanisms, such as colorimetric, fluorescent, and electrochemical methods. To finalize, the future development and trend in this field are discussed. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: The preparation of new adsorbents for heavy metals consisting of cellulose paper grafted with polyamine moieties is described. The tosylation of pristine cellulose paper allowed the subsequent displacement of the tosylated leaving groups with either ethylenediamine or spermine provided the corresponding cellulose-based polyaminated adsorbents Cell-Ed and Cell-Sperm, respectively. Optimizations related to the influence of experimental conditions (time and pH) on the adsorption processes associated to detailed studies devoted to the understanding of the mechanism of adsorption through kinetic experiments and isotherm modeling provided a rational understanding for the removal Cu(II) and Pb(II). Interestingly, Cell-Sperm also displayed outstanding adsorption properties for other metal cations such as Cd(II), Zn(II) and Fe(II).Graphical Abstract: [ABSTRACT FROM AUTHOR]

Municipal sewage sludge, paper mill sludge, and slaughterhouse sludge were pyrolyzed and liquefied for the production of bio-char. The migration and transformation behavior of Cu, Cr, and Zn during pyrolysis and liquefaction of these sludges were studied. Pyrolysis and liquefaction promoted mobile fraction (F1 and F2) to stable fraction (F3 and F4). The results showed that pyrolysis and liquefaction largely affected the redistribution of Cu and Zn in raw materials. The environmental risk assessment results indicated that the environmental risk levels of Cu and Zn were significantly reduced in bio-char, and risk level of Cr was slightly decreased after pyrolysis or liquefaction. Both pyrolysis and liquefaction were promising detoxification technologies for the three sludges in terms of the mitigation of heavy metals toxicity. It was suggested that dewatered sludge could be reduced toxicity/risk before utilization by pyrolysis or liquefaction technology, especially for Cu and Zn in slaughterhouse sludge. [ABSTRACT FROM AUTHOR]

This experiment was conducted to evaluate the effects of cadmium toxicity on the seed germination properties of sesame cultivars (Halil, Nazok Shakhei, Oltan, and Yellow White) using nonlinear growth models. Seeds were germinated in petri dishes (90mm diameter), with a double layered of filter paper soaked in distilled water as control treatment or cadmium (CdSO4) solutions in concentrations of 0, 100, 200, 400, 600, 800 and 1000 ppm. Each treatment was replicated four times and included 50 seeds in each petri dishes. Hyperbolastic growth models for the description of seed germination data were compared to Richards, Weibull, Logistic and Gompertz models. Our results revealed that all studied cultivars were germinated at the cadmium-polluted germination medium to a maximum of 200 ppm without reduction in germination fraction, while seed germination rate was decreased at this concentration compared to 0 and 100 ppm. Increasing cadmium concentration resulted in the germination fraction reduction from 1 to 0.4 at the 400 ppm. The recommended hyperbolastic growth model was type III or (H3) as it provided the best model with the lowest Corrected Akaike Information Criterion for cv. Halil (AICc =-14.6) and cv. Nazok Shakhei, (AICc =-14.2). Cette expérience a été menée pour évaluer les effets de la toxicité du cadmium sur la cinétique de germination de graines issues de différents cultivars de sésame (Halil, Nazok Shakhei, Oltan et Yellow White), en comparant des modèles de croissance non linéaire. Les graines ont germé dans des boîtes de Pétri (90mm de diamètre), entre deux couches de papier filtre imbibées d'eau distillée (contrôle) ou dans des solutions de cadmium (CdSO4) à des concentrations de 0, 100, 200, 400, 600, 800 et 1000 ppm. Chaque traitement a été répété quatre fois et comprenait 50 graines par boîte. Les cinétiques de croissances ont été modélisées avec modèles de croissance hyperbolastique, dont l'ajustement a été comparé aux modèles sigmoïdes classiques (Richards, Weibull, Logistic et Gompertz). Nos résultats ont révélé que tous les cultivars étudiés ont germé, sans réduction du taux de germination, jusqu'à une concentration de de 100 ppm. Au-delà, le taux de germination était réduit. À la concentration de 400 ppm, le taux de germination est passé de 1 à 0,4. Le modèle de croissance hyperbolastique recommandé était de type III ou (H3), car il présentait un critère d'information d'Akaike (AIC) corrigé le plus bas pour les cultivars Halil (AICc =-14,6) et Nazok Shakhei, (AICc =-14,2). [ABSTRACT FROM AUTHOR]

[Display omitted] • CysA@AuNPs supported amino acids was synthesized using hydrothermal protocol. • CysA@AuNPs supported was used for the identification of Hg(II) and Cu(II). • CysA@AuNPs have well activity for ion sensing in aqueous solution. In this study, an innovative methods was proposed for the synthesis of cysteamine@gold nanoparticle (CysA@AuNPs) using one step protocol. Also, application of CysA@AuNPs for the sensitive recognition of Hg (II) and Cu (II) in aqueous media was investigated using optical techniques. This research work explains the development of a lightweight stamp for manufacturing of a novel microfluidic paper-based analytical device (μ PADs), as a simple colorimetric sensor for selective recognition of Hg2+ and Cu2+ within the other metal ions (Fe(III), Mn(II), Zr(IV), Ba(II), Mg(II), Sr(II), As(III), B(III), Al(III), V(III), K(I), Na(I), Mo(II), Co(II), Zn(II), Sn(II), Se(IV), Cr(III), Bi(III)) in aqueous, and human biofluids. CysA@AuNPs supported amino acids were used as the ion detection probs. The specific colorimetric response of Hg2+ and Cu2+ amongst the other ions through the innovative sensor allows naked-eye discrimination of the mercury and copper metal ions in this work with excellent selectivity in the presence of cysteine, and methionine. The results revealed our new strategy (μ PADs) for the colorimetric recognition of mercury and copper ions, in both urine and aqueous samples, is selective, simple, fast, sensitive, quantitative, cost-effective, and eco-friendly, which can be detected by naked eye through color alternation with LLOQ of 0.001 ppm for Hg2+, and 0.02 ppm for Cu2+ with admirable stability. The low instrumental needs of the stamp, and disposability of μ PADs enable the application of the suggested paper-based device for the commercial diagnostics biosensor. [ABSTRACT FROM AUTHOR]

Heavy metal pollution in rivers and lakes arising due to rapid economic development has been extensively studied by various countries due to its direct impact on ecological health and human well-being. However, there is a lack of comprehensive and systematic reviews addressing the current research status of this subject. In this study, we conducted a visual metrological analysis of the literature from 2001 to 2021 using the Web of Science (WoS) and China National Knowledge Infrastructure (CNKI) citation databases. The results show that studies conducted in other countries initially outnumbered those in China; after 2010, China emerged as the foremost contributor. Furthermore, both the WoS and CNKI databases indicate active engagement of Chinese researchers through a significant proportion of published papers on metal research, with prominent contributions coming from institutions such as the Chinese Academy of Sciences (CAS) and University CAS. Nevertheless, Chinese research institutions still have relatively low total paper citation numbers and have yet to establish themselves as key players in international scientific research efforts. Additionally, core authors from different countries share substantial similarities in their research directions and focuses. Consistent research hotspots regarding heavy metals in rivers and lakes were identified across both databases, including heavy metal pollution, adsorption, human activities, water quality, and sediment. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Agro-Environment Science is the property of Journal of Agro-Environment Science Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, Web of Science (a database) is used to retrieve related literature in the field of heavy metal pollution in desert. CiteSpace is used to make a quantitative and qualitative evaluation on the literature in the field on the basis of a brief analysis on the research status, research focus, and evolution process in the field. Through CiteSpace visual analysis, a comparative analysis is given on related literature in terms of annual number of published papers, author groups, and their countries and regions, journals, publishing institutions, highly cited papers, research focuses, and burst terms, so as to explore the research status and future development trend of the field on a global scale. The results are shown as follows: (1) The literature in the field was originally published in 2000; the number of published papers increased steadily. The literature was mostly published on high-quality journals, the USA topped in terms of the number of published papers, and the research results achieved by developed countries had a greater influence. Chinese Acad Sci topped with the highest centrality and most published papers, which have made outstanding contributions to the field and occupy a leading position in the field. However, the fact is that there lacks communication and cooperation among research institutions. The most influential journal is Science of the Total Environment. (2) The hot research words in the field are as follows: heavy metal, soil, pollution, lead, desert, cadmium, and microelement. (3) In the field, burst terms have transformed from atmospheric deposition, biomonitoring, and phytoremediation to trace element, stream sediment, street dust, and water quality, and finally transformed to river and sediment. New words keep emerging in the research, and more and more attention is paid to the issue of heavy metal pollution in river sediment, which will be a future research hotspot in the field. [ABSTRACT FROM AUTHOR]

Phytoremediation is recognized as an environmentally friendly technique. However, the low biomass production, high time consumption, and exposure to combined toxic stress from contaminated media weaken the potential of phytoremediation. As a class of plant-beneficial microorganisms, arbuscular mycorrhizal fungi (AMF) can promote plant nutrient uptake, improve plant habitats, and regulate abiotic stresses, and the utilization of AMF to enhance phytoremediation is considered to be an effective way to enhance the remediation efficiency. In this paper, we searched 520 papers published during the period 2000–2023 on the topic of AMF-assisted phytoremediation from the Web of Science core collection database. We analyzed the author co-authorship, country, and keyword co-occurrence clustering by VOSviewer. We summarized the advances in research and proposed prospective studies on AMF-assisted phytoremediation. The bibliometric analyses showed that heavy metal, soil, stress tolerance, and growth promotion were the research hotspots. AMF–plant symbiosis has been used in water and soil in different scenarios for the remediation of heavy metal pollution and organic pollution, among others. The potential mechanisms of pollutant removal in which AMF are directly involved through hyphal exudate binding and stabilization, accumulation in their structures, and nutrient exchange with the host plant are highlighted. In addition, the tolerance strategies of AMF through influencing the subcellular distribution of contaminants as well as chemical form shifts, activation of plant defenses, and induction of differential gene expression in plants are presented. We proposed that future research should screen anaerobic-tolerant AMF strains, examine bacterial interactions with AMF, and utilize AMF for combined pollutant removal to accelerate practical applications. [ABSTRACT FROM AUTHOR]

The problem of persistent and potentially toxic heavy metal-contaminated soils is widespread worldwide. These heavy metal concentrations have continued to accumulate in soils over the past three decades, posing a threat to the environment and human health. Therefore, the problem of heavy metal soil contamination needs to be addressed urgently. In this paper, we describe the sources of heavy metal pollution and their hazardous properties, emphasizing the urgent need for treatment. Traditional remediation techniques for heavy metal contamination include physical, chemical, and biological methods. Each of these methods has its advantages and disadvantages and can be combined to remove (transform) or reduce heavy metals in contaminated soils to safe levels. The article provides a comparative analysis of traditional remediation techniques for heavy metal contamination, focusing on a review of the current status of research and application of microbial remediation methods in heavy metal contamination of mine soils. The paper also discusses the combined microbial and chemical/plant remediation techniques. In conclusion, the remediation and treatment of heavy metal-contaminated soils should consider both the economy and effectiveness of the remediation technology. Microbial remediation is a typical remediation technology that will become the main development trend due to its effectiveness and low cost. [ABSTRACT FROM AUTHOR]

Composting is an effective and cost-efficient engineering technique used to treat agricultural waste. It involves the conversion of organic materials into stable compounds and the rapid degradation of organic matter through microorganisms found in feces. The resulting high-quality fertilizer can improve soil physical, chemical, and biological properties. However, the excessive use of heavy metals in livestock breeding can restrict the use of livestock manure for composting. Long-term application of compost products containing heavy metals can cause irreversible damage to farmland soil environments. This paper summarizes several important factors that affect the detoxification of heavy metals in composting and discusses the passivation effect of typical heavy metal passivators. The detoxification mechanism of heavy metals in compost is summarized from two perspectives: the humification effect of heavy metals and the environmental interface effects of microorganisms. This paper provides a foundation for improving the agronomic use value of avian manure aerobic composting products and for studying heavy metal passivation in compost. The application of aerobic composting in the remediation of petroleum-contaminated soil exhibits a dual impact, primarily focusing on the synergistic effects on petroleum hydrocarbon degradation and soil improvement. Such research endeavors are poised to offer innovative solutions towards achieving comprehensive restoration of petroleum-contaminated soils. [ABSTRACT FROM AUTHOR]

Community gardens are often seen as a means for producing sustainable food resources in urban communities. However, the presence of trace metals and metalloids such as lead, arsenic, and cadmium in urban soils poses a health risk to gardeners who participate in urban community gardens. They are exposed to these contaminates through multiple exposure pathways such as inhalation and ingestion directly through soil or through crops grown in the soil. Hot spots of soil contamination are higher in areas of cities with greater minority populations and lower incomes. This paper reviews the state of heavy metal contamination in community garden soils across the United States. This paper outlines the major sources of heavy metals in urban soils, exposure pathways, the ways to reduce heavy metal levels in garden soils, the means to slow down the uptake of heavy metals, and limit the exposure of these contaminates. The application of biochar and compost, implementing raised beds, and maintaining a natural pH are all examples of ways to mitigate heavy metal contaminants. [ABSTRACT FROM AUTHOR]

Soil contamination presents a significant hazard to both ecosystems and human well-being. Therefore, there is a need for cost-effective and environmentally friendly approaches to decontaminate polluted soils. Soil remediation involves the treatment of contaminated land to enhance soil quality, safeguarding public health and the ecosystem. Among the promising technologies for remediating soils contaminated with various substances, including inorganic, organic, and mixed contaminants, is electrochemical remediation. Electroremediation (ER) is an in-situ method that employs low direct electric current among electrodes fixed in contaminated soils to create an electric field. This review paper examines the advancements made in recent years in electrochemical remediation as an effective method for decontaminating polluted soil. The discussion begins by exploring electrochemical remediation, followed by the classification of contamination types in soil. The focus then shifts to the application of electrochemical treatment methods for removing heavy metals and organic contaminants from the soil. Additionally, the paper highlights recent progress in the exploration of integrating electrochemical treatment with other remediation techniques, such as phytoremediation and bioremediation. [ABSTRACT FROM AUTHOR]

Soil heavy metal pollution is one of the hottest topics in soil environmental research. There are a large number of small abandoned metal mines in China. Due to the lack of timely restoration and treatment, the heavy metal concentration in the soil within these mining areas often exceeds the local background levels, facilitating pollution spread to other natural factors such as precipitation, resulting in a wider extent of continuous contamination. This paper investigates the current status of heavy metal pollution in an abandoned small lead-zinc mine, particularly examining the concentrations of 10 specific heavy metals (V, Cr, Ni, Zn, As, Cd, Hg, Pb, Cu, Co) in soil samples. Additionally, it explores the extent of contamination caused by these heavy metals within the area. Besides, principal component analysis and positive matrix factorization model (PMF) were adopted to determine the sources of these heavy metals. The risk assessment of the pollution status was also carried out. The provision of a scientific basis for mining area management under similar conditions holds significant importance. The results indicate a significant positive correlation among the majority of these 10 heavy metals in soil. The presence of these heavy metals in the soil within the concentrator and tailings reservoir area primarily stems from mining operations, construction activities, and discharges from the power system. Hg, Pb, Zn, and As in the surrounding agricultural land mainly come from the heavy metal spillover from the mining area. Furthermore, the area is plagued by severe contamination from As and Pb. The Nemerow comprehensive index method has confirmed substantial pollution in both the concentrator and tailings reservoir. Additionally, there exists a substantial ecological risk ranging from moderate to high. [ABSTRACT FROM AUTHOR]

Recent advancements in urban economies and population growth have led to an escalation in urban soil heavy metal pollution, thereby posing significant threats to human life and health. This paper presents a comprehensive bibliometric analysis, detailing the developmental trajectory, research hotspots, and emerging trends in the field of urban soil heavy metal pollution research. Utilizing the CiteSpace and VOSviewer software tools, we conducted an analysis of 1247 articles sourced from the Web of Science Core Collection Database (WoSCC) spanning the period from 2000 to 2022. Our analysis revealed a significant upward trend in the number of publications during the period 2000–2022, a trend expected to persist. Ahmad Kafeel, Khan Zafar Iqbal, and Huang Biao emerged as the leading authors in this domain. The journal, Science of the Total Environment, held the most influence, while China led in the number of publications, with the Chinese Academy of Sciences as the foremost contributor. The research predominantly focused on source apportionment of urban soil heavy metal pollution, pollution risk assessment, and the application of environmental magnetism. Future research priorities include assessing the human health risks from diverse sources of heavy metal pollution, a key aspect of ensuring urban safety and soil health. Our findings delineate the evolutionary trajectory of urban soil heavy metal pollution research over the past two decades and underscore the viability of employing a dynamic bibliometric approach to investigate this research discipline. [ABSTRACT FROM AUTHOR]

Numerous research papers on biosorption have been published in the past four decades. This paper reviews and compares heavy metal uptake capacities of various biological and non-biological materials. Adsorption mechanisms and processes of heavy metal ions (HMIs) onto biomasses are summarised and discussed, respectively. In general, all types of adsorbents exhibit certain uptake capacities for HMIs, but the capacity values for different types of biomasses and non-biological materials vary significantly. For HMIs, the reported values for bacterial biomasses typically range from 0.06 mmol·g−1 to 2.84 mmol·g−1; for fungi and yeasts, 0.03 mmol·g−1 to 2.44 mmol·g−1; for fresh water algae, 0.02 mmol·g−1 to 3.15 mmol·g−1; for marine algae, 0.23 mmol·g−1 to 3.77 mmol·g−1; for other biological materials/derivatives, 0.01 mmol·g−1 to 1.78 mmol·g−1 and for non-biological materials, 0.003 mmol·g−1 to 2.40 mmol·g−1. Thereinto, a few macroalgal species exhibit much higher adsorption capacities for HMIs relative to other types of adsorbents. Statistical analysis of heavy metal uptake capacities of various biological and non-biological materials indicates that marine algae are most suitable for the development of industrial biosorbents for the remediation of diluted HMIs-bearing effluents. Biosorption mechanisms of HMIs by biomasses include physical adsorption, ion exchange, electrostatic interaction, surface complexation and inorganic microprecipitation. the physicochemical properties of biosorbents and HMIs as well as external adsorption conditions significantly influence the adsorption process of HMIs onto biomasses. It could be concluded from numerous previous studies that pseudo-first-order and pseudo-second-order models are the most commonly utilised to characterise adsorption process. Up to date biosorption of HMIs remains largely in the laboratory stage. Combining microscopic mechanisms with macroscopic models may be one of the future research directions for removal of HMIs by biomasses. [ABSTRACT FROM AUTHOR]

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This paper refers to a survey conducted in Zhengzhou section of the Yellow River for the purpose of investigating heavy metal pollution characteristics and of exploring the pollution sources. Monitoring was thereby carried on August 29-31, 2022 along the riparian zone collecting samples of the river sediments and analyzing the concentrations of nine kinds of heavy metal, including Cd, Pb, Cu, Zn, As, Hg, Cr, Ni and Mn. Then the Tessier five-step sequential extraction method was used for the morphological analysis of the heavy metals; the ground accumulation index (Igeo) was used to evaluate heavy-metal pollution degree, with Nemero pollution index being applied to the comprehensive assessment of the pollution situation; and the principal component analysis (PCA) and absolute factor analysis-multiple linear regression analysis model (APCS-MLR) were used to analyze the source of the pollutants. Consequently, the survey showed that both of the mean concentrations of Pb and Cd in the sediments of the riverine zone of Zhengzhou section of the Yellow River exceeded the soil background value of heavy-metal in Henan Province. Results of the speciation analysis showed that the environmental activities of Mn, Cd, Pb and Hg were relatively high; the evaluation of geo-accumulation index (Igeo) indicated that Cd had resulted in slight to moderate pollution in the sediments of the River; and the evaluation results of the Nemero pollution index showed that all the above-mentioned heavy-metal elements were on the safety level. Result of the source apportionment suggested that tannery industry, agricultural activities and automobile parts production, as well as the natural source were the major heavy-metal pollution sources in the riparian zone of Zhengzhou section of the Yellow River. [ABSTRACT FROM AUTHOR]

Traditionally, the assessment of heavy metal concentrations using remote sensing technology is sample-intensive, with expensive model development. Using a mining area case study of Daxigou, China, we propose a cross-time-domain transfer learning model to monitor heavy metal pollution using samples collected from different time domains. Specifically, spectral indices derived from Landsat 8 multispectral images, terrain, and other auxiliary data correlative to soil heavy metals were prepared. A cross time-domain sample transfer learning model proposed in the paper based on the TrAdaBoost algorithm was used for the Cu content mapping in the topsoil by selective use of soil samples acquired in 2017 and 2019. We found that the proposed model accurately estimated the concentration of Cu in the topsoil of the mining area in 2019 and performed better than the traditional TrAdaBoost algorithms. The goodness of fit (R2) of the test set increased from 0.55 to 0.66; the relative prediction deviation (RPD) increased from 1.37 to 1.76; and finally, the root-mean-square deviation (RMSE), decreased from 8.33 to 7.24 mg·kg−1. The proposed model is potentially applicable to more accurate and inexpensive monitoring of heavy metals, facilitating remediation-related efforts. [ABSTRACT FROM AUTHOR]