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Purpose This work deals with the application of a solidification/stabilization process with the aim to obtain safe and reusable granular materials from a polluted soil and to elucidate the mechanisms involved in the retention of several heavy metals. Materials and methods The High Performance Solidification/Stabilization (HPSS®) process was applied to the selected contaminated soil by using both ordinary Portland cement and calcium aluminate cement, as well as several binders prepared by combining these two types of cement in different proportions. Leaching and mechanical tests were carried out to evaluate the performances of the proposed binders in the pellets produced by the HPSS® process, while XRD analysis and SEM/EDX imaging were used to investigate the phase composition and internal microstructure of the treated samples. Result and discussion The examination of the obtained granular materials revealed that the immobilization of Sb was mainly related to its inclusion within calcium silicate hydrates’ structure; the immobilization of Cr, Pb, Ni, Co, Zn and Tl was associated with the eluate pH and their incorporation within ettringite structure, while for Se, Cu, Ba and V, the main retention mechanism was physical encapsulation. In addition, the application of a wet conditioning process improved the materials’ performance, leading to granules always satisfying the Italian regulatory requirements for reuse. Conclusions The findings obtained in this study were useful to better elucidate the mechanisms involved in the retention of heavy metals by several binders, contributing to the development of sustainable management strategies for contaminated soils and sediments through their transformation into reusable materials. Graphical abstract

The progression of urban industrialization releases large quantities of heavy metals into water, resulting in the severe heavy metal contamination of the aquatic environment. Traditional methods for removing heavy metals from wastewater generally have varying removal efficiencies, whereas algae adsorption technology is a cost-effective and sustainable bioremediation technique. A green technology that immobilizes algae through a carrier to improve biosorbent’s stability and adsorption performance is immobilization technology. The purpose of this review is to study the optimization strategy of the immobilization of algae for the bioremediation of heavy metals and to comprehensively analyze immobilized algae technology in terms of sustainability. The analysis of the mechanism of heavy metal removal by immobilized algae and the parameters affecting the efficiency of the biosorbent, as well as the approach based on life cycle assessment and economic analysis, allowed the identification of the optimization of the adsorption performance of immobilized algae. This provides a theoretical basis for the practical application of algal bioremediation.

The treatment of metal-contaminated sediment generated in environmental dredging projects often requires both reduction and remediation, and the electric field has good application prospects in the integration of reduction and remediation. In this study, based on the electro-osmosis, vacuum, and vacuum electro-osmosis methods, a detachable test system was made. Experiments of the three methods were carried out independently on the reduction and remediation of dredged sediment from Tai Lake under pollution-free and Cu-contaminated conditions. The results show that copper contamination weakens the effect of reduction, and the production of copper precipitates makes the soil more prone to cracking and blocking drainage channels, which has the greatest impact on the electro-osmosis method. In terms of copper concentration, vacuum electro-osmosis achieves the transport and discharge of contaminants, and has the best remediation effect. The removal rates at the anode and cathode are 45.1% and 50.0%, respectively. A correlation model based on electrical conductivity, moisture content, and contaminant concentration was established to facilitate the determination of contaminant concentrations in actual projects. Electro-migration plays a dominant role in the remediation process, and the reduction affects the electric field distribution and, thus, the migration efficiency.

11 páginas.- 8 figuras.- 5 tablas.- 52 referencias.- Supplementary data to this article can be found online at https://doi.org/10.1016/j.envpol.2021.118025, Biochar application to soils has become a focus of research during the last decade due to its high potential for C sequestration. Nevertheless, there is no exhaustive information on the long-term effects of biochar application in soils contaminated with trace elements. In this work, a 2-year field experiment was conducted comprising the application of different types of biochar to acidic and moderately acidic soils with high concentrations of As, Cu, Pb, Ba and Zn. In addition, representative samples of each biochar were buried in permeable bags that allowed the flow of water and microorganisms but not their physical interaction with soil aggregates. The biochars significantly adsorbed trace elements from polluted soils. However, given the high total concentration of these persistent trace elements in the soils, the application of biochars did not succeed in reducing the concentration of available metals (CaCl2 extractable fraction). After 2 years of ageing under field conditions, some degradation of the biochars from olive pit, rice husk and wood were observed. This study provides novel information concerning the biochar alterations during ageing in polluted soils, as the decrease of aryl C signal observed by 13C nuclear magnetic resonance (NMR) spectroscopy and the presence of O-containing groups shown by Fourier Transform mid-Infrared Spectroscopy (FT-IR) in aged biochar which enhanced trace elements adsorption. Scanning electron microscopy (SEM) revealed slight changes on surface morphology of aged biochar particles., EI / FEDER and The Spanish Ministry of Economy, Industry and Competitiveness (MINEICO) are acknowledged for funding this research [projects CGL2016-76498-R and CGL2015-64811-P]. P. Campos is grateful to “Fundaci ́on Tatiana P ́erez de Guzm ́an el Bueno” is thanked for funding pre-doctoral contract of Paloma Campos. MINEICO is also thanked for funding the post-doctoral contract (Ram ́on y Cajal) of J.M. De la Rosa. ́Agueda S ́anchez-Martín and Araceli de la Rosa are thanked for technical assistance in laboratory and field.

Substances found in watersheds and sediments in artisanal and small-scale gold mining (ASGM) areas contaminated by heavy metals are becoming tremendously critical issues in Asia. This study aimed at clarifying the pollution caused by heavy metals in sediments in river basins near ASGM sites in Gorontalo Province, North Sulawesi, Indonesia. Sediment samples collected from experimental areas were classified into nine clay samples and twenty-seven sand samples, whereas three other samples were collected from the control area. Particle-induced X-ray emission was used to analyze these samples. The Statistical Package for the Social Science and the geo-accumulation index (Igeo) were also used for analysis. Based on the results, Hg, Pb, As, and Zn had a concentration of 0–334 µg/g, 5.5–1930 µg/g, 0–18,900 µg/g, and 0–4923.2 µg/g, respectively, which exceeded limits recommended by the U.S. Environmental Protection Agency consensus (1991) and the Indonesian Government Regulation Number 38, 2011. Furthermore, Igeo showed the order of the pollution degree Hg < Zn < Pb < As and reflected an environment contaminated by heavy metals, ranging from unpolluted to extremely polluted areas. Therefore, sediments contaminated by Hg, Pb, As, and Zn could be found along the river basin of mining areas.

Graphical abstract, Indiscriminate disposal of wastes on landfills has led to increase in heavy metal contamination in landfill soils. However, the ability of the indigenous microorganisms to remediate the polluted environment can be of great influence in reclamation of such soils. The objectives of this study were to assess the bioremediation potential of the screened indigenous bacteria and evaluate the effects of carbon source and pH in the enhancement of the bioremediation process. Bacterial isolates from landfill sites were screened for their capability to utilize heavy metal (Cd and Pb). Nutrient Agar was supplemented with five different concentrations of each metal (25 to 600 mgL-1). Viable counts of the isolates were taken four times at two days interval. Pseudomonas aeruginosa, Klebsiella edwardsii and Enterobacter cloacae were selected based on their tolerance to heavy metal for remediation process. Peptone broth was also supplemented using different concentrations of heavy metals. The remediation process was assessed by monitoring the growth of biomass using UV spectrophotometer at 600 nm and the residual heavy metal was evaluated after 8 days of incubation using AAS. Pseudomonas aeruginosa exhibited the highest bioremediation potential among the bacterial isolates with 58.80 and 33.67 remediation percentage in 50 mg Cd L-1 and 300 mg Pb L-1 . However, higher remediation percentage (79.87 and 92.41) was observed by Klebsiella edwardsii through addition of carbon source (5 g/L) and varying the pH (6) of the media in the heavy metal contaminated medium. The results of this study indicate that the effectiveness of the indigenous bacteria in remediation process can be enhanced through the addition of carbon source and increase pH for effective reclamation of contaminated soil.

This paper quantified the level of heavy metals contamination, identified possible sources of pollution, and assessed the human health risks associated with drinking water resources in Ojoto Province, Nigeria. The study’s gross findings revealed that the suitability of some water sources for consumption purposes in this province is questionable. Based on water quality index, 57.14% of the total samples are within acceptable limits, while 42.86% are unsuitable for drinking. It was observed that the northwestern and southern parts of the study area have more of deteriorated water quality. The health hazard index revealed that 25% of the samples predispose their consumers (both adult and children populations) to high chronic health risks. Moreover, heavy metal pollution index, contamination index, and probability of cancer risk (CR) revealed that about 25% of the total samples were unsuitable and off the CR standard acceptable range of ≤ 1 × 10−6–1 × 10−4. Correlation and component factor analyses linked the origin of major ions to geogenic processes and that of the heavy metals to both natural and anthropogenic processes. Cluster analysis divided the samples into two equal classes (50% each): poor and excellent quality waters. This study indicated that Pb is the priority pollutant impacting the water quality. The various assessments revealed that waters from hand-dug wells and deeper boreholes are the least contaminated and hence best suited for drinking than waters from springs, streams, and shallow wells.

Heavy metals cause deleterious effects on human health and drastically alter the biogeochemical cycles within freshwater habitats. The main human activities leading to heavy metal contamination of various aquatic ecosystems comprise the industry, agriculture, urbanization, transport and mining. Lake Nasser is the main freshwater source in Egypt, usually polluted from upstream human activities from the hydrographic basin of the River Nile. The current study surveyed the impact of heavy metals contamination (i.e., Cd, Zn, Pb and Cu) in water, sediment and two Nile Tilapia (Oreochromis niloticus) fish organs (liver and muscles) at six sampling sites along Lake Nasser. Additionally, the effects of heavy metals bioaccumulation in the aquatic ecosystem, via water, sediments and fish organs were investigated. The conclusion is that the water of Lake Nasser is safe for use in terms of human consumption, agricultural utilization and public sanitation.

The pollution of agricultural soils by the heavy metals affects the productivity of the land and has an impact on the quality of the surrounding ecosystems. This study investigated the bacterial community structure in the heavy metal contaminated sites along a smelter and a distantly located paddy field to elucidate the factors that are related to the alterations of the bacterial communities under the conditions of heavy metal pollution. Among the study sites, the bacterial communities in the soil did not show any significant differences in their richness and diversity. The soil bacterial communities at the three study sites were distinct from one another at each site, possessing a distinct set of bacterial phylotypes. Among the study sites, significant changes were observed in the abundances of the bacterial phyla and genera. The variations in the bacterial community structure were mostly related to the general soil properties at the phylum level, while at the finer taxonomic levels, the concentrations of arsenic (As) and lead (Pb) were the significant factors, affecting the community structure. The relative abundances of the genera Desulfatibacillum and Desulfovirga were negatively correlated to the concentrations of As, Pb, and cadmium (Cd) in the soil, while the genus Bacillus was positively correlated to the concentrations of As and Cd. According to the results of the prediction of bacterial community functions, the soil bacterial communities of the heavy metal polluted sites were characterized by the more abundant enzymes involved in DNA replication and repair, translation, transcription, and the nucleotide metabolism pathways, while the amino acid and lipid metabolism, as well as the biodegradation potential of xenobiotics, were reduced. Our results showed that the adaptation of the bacterial communities to the heavy metal contamination was predominantly attributed to the replacement process, while the changes in community richness were linked to the variations in the soil pH values.

In this study, copper toxicity, was investigated after the addition of zeolite to the diet of common carps (Cyprinus carpio). The experiment included four groups with three replicates each. The 4 group feeds were [CuSO4; CuSO4 + Zeolite; Zeolite, and the control without CuSO4 or Zeolite with three replicates each. Fishes were kept in 80 L glass aquariums with 10 fishes with a mean weight of 60.6 ± 0.2 g. At the end of each period, a necropsy was performed on fishes from each treatment, and gross clinical signs were recorded. We found significant changes in the blood parameters of the common carps with or without different levels of zeolite and copper. Changes in cholesterol (CHOL), triglyceride (TG), low density lipoprotein (LDL), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), calcium (Ca2+), phosphorus (P+), sodium (Na+), potassium (K+), chloride (Cl-), magnesium (Mg2+), and ferrous (Fe+2) were also significant. Our results suggest that zeolite can be used in fish feeds at a rate of 40 mg/l to mitigate the toxic effects of copper.

Heavy metal pollution of soil, water bodies and air is one of the alarming issues in all over the world. The present investigation mainly deals with the isolation, identification and screening of the metal sorption capacity of indigenous fungal strains isolated from iron mining area, Barbil, Odisha, India. Major fungal genera observed were Aspergillus sp., Rhizopus sp., Fusarium sp., Penicillium sp., Trichoderma sp., etc. Iron tolerance studies were carried out on Potato dextrose agar and Czapekdox agar using disc diffusion method with FeCl3 concentrations ranging from 200 to 1000 mg/l. Out of 14 isolates, 6 showed maximum tolerance at 1000 mg/l. The percentage of iron removal was maximum i.e. 96.62% by Aspergillus japonicus strain VIT-SB1 at 36 hrs at pH 6 and ambient temperature without any pre-treatment of fungal biomass. Hence, the isolated fungi exhibits great tolerance to iron and can be used successfully for bioremediation purpose.

Miscanthus x giganteus is a high biomass producing plant with tolerance to heavy metals. This makes Miscanthus interesting to be used for phytoremediation of heavy metal contaminated areas coupled with energy production. Since plant performance in metal polluted areas is impaired, their growth and phytoremediation effect can be improved with bacterial assistance. To identify positive and negative responders of M. x giganteus associated microbiome influenced by Cd, Pb and Zn stress compared to noncontaminated controls, we designed a greenhouse experiment. Structure of the bacterial community in three rhizocompartments, namely rhizosphere, rhizoplane and root endosphere was analysed using an isolation independent molecular approach based on 16S rRNA gene barcoding. Furthermore, quantitative PCR (qPCR) was used for bacterial biomass estimation. Our results indicated that biomass and total bacterial diversity in rhizosphere, rhizoplane and root endosphere did not significantly change despite of substantial root uptake of heavy metals. Overall, we detected 6621 OTUs, from which 171 were affected by metal addition. Whereas Streptomyces and Amycolatopsis taxa were negatively affected by the heavy metal treatment in endosphere, taxa assigned to Luteolibacter in rhizosphere and rhizoplane (log(2) fold change 1.9-4.1) and Micromonospora in endosphere (log2 fold change 10.2) were found to be significantly enriched and highly abundant (0.1-3.7% relative abundance) under heavy metal stress. Those taxa might be of key importance for M. x giganteus performance under heavy metal pollution and might be interesting candidates for the development of new bioinocula in the future to promote plant growth and phytoremediation in heavy metal contaminated soils. (C) 2019 Elsevier B.V. All rights reserved.

This study was performed to improve the ability to predict the concentrations of Escherichia coli in oyster meat and estuarine waters by using environmental parameters, and microbiological and heavy metal contamination from shellfish growing area in southern Thailand. Oyster meat (n = 144) and estuarine waters (n = 96) were tested for microbiological and heavy metal contamination from March 2016 to February 2017. Prevalence and mean concentrations of E. coli were 93.1% and 4.6 × 103 most probable number (MPN)/g in oyster meat, and 78.1% and 2.2 × 102 MPN/100 mL in estuarine water. Average 7-day precipitation, ambient air temperature, and the presence of Salmonella were associated with the concentrations of E. coli in oyster meat (p < 0.05). Raw data (MPN/g of oyster meat and MPN/100 mL of estuarine water) and log-transformed data (logMPN/g of oyster meat and logMPN/100 mL of estuarine water) of E. coli concentrations were examined within two contrasting regression models. However, the more valid predictions were conducted using non-log transformed values. These findings indicate that non-log transformed data can be used for building more accurate statistical models in microbiological food safety, and that significant environmental parameters can be used as a part of a rapid warning system to predict levels of E. coli before harvesting oysters.

The uptake of nickel [Ni(II)] by Paenibacillus sp., Methylobacterium sp., Paraburkholderia sp., and Pseudomonas sp. strains isolated from a boreal bog was studied using batch experiments. All strains removed Ni(II) from the solution and the uptake efficiency was affected by the nutrient source, incubation temperature, time, and pH. As highest Ni uptake (with a maximum Kd of 1890 L/kg DW) was recorded for the Pseudomonas sp. strains, these bacteria were used in the following protein expression (SDS-PAGE and MALDI-TOFF), transmission electron microscopy (TEM) and EDS experiments. In addition, Freundlich and Langmuir sorption isotherms were determined. In the Ni(II) treated cells, dense crystalline intra-cellular accumulations were observed in TEM examinations, which were identified as Ni accumulations using EDS. SDS-PAGE and MALDI-TOFF spectra of Ni(II) treated cells showed several changes in the protein profiles, which can indicate active accumulation of Ni in these bacteria. Concurrently, we observed Ni(II) uptake to follow Freundlich and Langmuir isotherms, suggesting straight cellular biosorption in addition to the intra-cellular accumulation. The role of cellular (cell membrane and cell wall) functional groups involved in Ni(II) binding were therefore studied using Fourier transformation infrared spectroscopy. These analyses supported the potential role of the alcoholic hydroxyl, carboxyl and amine groups in Ni(II) binding in these bacteria, therefore suggesting two different Ni(II) uptake mechanisms; (i) intra-cellular accumulation [possibly connected to detoxification of Ni(II)], and (ii) straight biosorption on cell membrane/wall functional groups.

Elevated concentrations of heavy metals in water can cause deformities of the mouthparts in chironomid larvae reared on artificial sediment. This investigation is an attempt to study effects of increased copper concentrations on mouthparts deformities of Chironomus plumosus larvae reared on natural sediment obtained from carp pond. Since the bioavailability of heavy metals is greater in artificial substrates than in natural ones usage of carp pond sediment, especially due to its low heavy metals content according to sediment quality guidelines, should provide more realistic assessment of biomarker potential of chironomid mouthparts deformities in biomonitoring of copper sediment pollution. It is demonstrated in the experiment that an increase of copper concentration in sediment leads to progressive increase in the frequency and severity of deformities of the mentum in C. plumosus larvae. Thus, shortening of median teeth in 2.0 +/- 0.2% individuals was the only deformity recorded in control tanks (at 15 mu gg-1 Cu), at 30 mu gg-1 Cu its frequency increased to 16 +/- 2%, and shortening of median-lateral teeth appeared at the same frequency, while at 60 mu gg-1 Cu frequency of both deformities increased to 24 +/- 2% and 28 +/- 4%, respectively, in addition to the appearance of tooth loss in 16 +/- 3% of individuals.

The goal of this research was to evaluate the chemical composition of some herbal products consumed in Brazil through the Energy Dispersive X-ray Fluorescence (EDXRF). The methodology used encompassed the selection of 14 plants’ dried extracts and six ground plants. The qualitative and quantitative analyses of samples indicating the presence of As, Cr, Cu, Fe, Ni, Zn, Si, P, S, Cl, K, Ca, Ti, V, Mn, Co, Rb, Zr, Cd, Sn, Ba, Hg, Pb, Bi, Mo, and Pt in different concentrations. It is feasible that part of the contamination found in the herbal products come from the adjuvants/excipients used in the production process. Also, it was found that the extract production process seems to have a low efficiency for the extraction of the main chemical elements present in the ground plants. In the other hand, it has the benefit of reducing the contamination by harmful elements to health, such as heavy metals. EDXRF can replace atomic absorption spectrometry as low-cost and high precision technique to quantify all elements of interest in the pharmaceutical and food industries, within the limits established by regulatory agencies

This paper focus on how to treat the wastewater after soil washing since water pollution is a severe threat to the water security of China. Ca (OH)2 and two kinds of biochars (biochar and ZnCl2 modified biochar) were tested to treat the waste FeCl3 washing effluent. Two kinds of biochars (biochar and ZnCl2-modified biochar) were prepared from maize straws. Soil samples were collected near a smelter for adsorption experiments. ICP-OES was used to determine the concentration of metal ions in the samples, as well as calculating their adsorption capacity and removal rate. As to Ca(OH)2 treatment, the maximum removal rates of Cd, Pb, Cu, and Zn could exceed 99%, and the concentrations of Cd, Pb, Cu, and Zn in solution could reduce to 0.08, 0.018, 0.15, 0.44 mg/dm3, respectively. However, both of the two biochars had relatively low removal rates compared with Ca (OH)2 treatment. The wastewater shows significantly lower environmental implications after the two treatments, and the lime precipitation method has better effects than biochar adsorption. The activated carbon adsorption method discussed can significantly improve the environmental pollution caused by soil washing wastewater, which is suitable for environmental treatment projects.

Steel slag has been used widely as an aggregate in road application, but it could pose a contamination risk for the environment due to considerable heavy metals (HMs). To explore the leaching behavior and contamination risk of HMs from steel slag and its asphalt mixture is of great significance. In this study, the physical-chemical features, batch leaching test and semi-dynamic test were conducted to determine the mobility capability and leaching characteristics of HMs. The results show that steel slag presents a low pollution risk in short-term leaching, whereas the cumulative release mass of Cd, Ni, As and Pb are more than or approach the limits, which indicates that steel slag exhibits environment impacts to a certain extent. Steel slag covered with asphalt binder results in As and Cu reduced by 3.64% and 4.83%. Diffusion is the main controlling mechanism of HMs in asphalt mixture and the mobility capability of most HMs were classed as &ldquo, low mobility&rdquo, (LI &gt, 8). Asphalt stripping off can aggravate the release potential of HMs from asphalt mixture, but the pollution risk remains controllable.

Loess soil is a kind of widespread soil type in northwest China. Human engineering activities such as mining have caused numerous problems related to heavy metal pollution in soils, which threaten people&rsquo, s health. The band formation mechanism of the near-infrared (NIR) spectral features in loess soils forms the theoretical basis for the study of the soil environment by hyperspectral remote sensing. Some NIR features of loess soils will shift because of the variations of the soil composition and microstructure after they adsorb heavy metal cations. In this study, we focused on the heavy metal adsorption of the illite, smectite, and illite&ndash, smectite (I/S) mixed layer in loess soils, evaluated the pollution by Nemerow indexing, applied X-ray diffraction (XRD), mid-infrared (MIR) spectral analysis, and inductively coupled plasma mass spectrometry (ICP-MS), and carefully observed the shift behavior of the MIR and NIR features. Then, the NIR bands were assigned to MIR bands according to the vibration behavior. Furthermore, the relationships between the NIR band positions and the six heavy metal cations as well as the Nemerow index were investigated via multiregression and simple linear correlation methods. Finally, the relationship obtained from the experiments was analyzed using the physical and chemical mechanisms of the heavy metal cations in the clay minerals. These findings may benefit the application of NIR and remote sensing techniques for detecting heavy-metal-polluted soils.

A busca por medidas sustentáveis para melhorar e suprir a demanda por alimentos que o crescimento populacional exige, aliado a escassez de terras produtivas, além do acúmulo excessivo de metais no ambiente devido a atividades como mineração e aplicação de fertilizantes no solo, foram as duas problemáticas que motivaram o presente estudo. O uso de fungos promotores do crescimento vegetal: Beauveria bassiana, Metarhizium anisopliae, Pochonia chlamydosporia, Purpureocillium lilacinum e Trichoderma asperella, pode tanto vir a influenciar o aumento da produtividade como potencializar a fitorremediação de metais pesados no solo. Esses fatos são explicados pela capacidade do consórcio fúngico de sintetizar e induzir as plantas a produzir fitohormônios direcionados para o melhor desenvolvimento das raízes do hospedeiro. O maior desenvolvimento de raízes pode estimular a fitoextração de metais do solo e conferir tolerância das plantas à contaminação. Na intenção de avaliar a influência dos fungos no desenvolvimento das plantas, foram realizados tratamentos das sementes de soja e milho e aplicação na parte aérea da cultura da cana-de-açúcar. Já para analisar a influência desses organismos no processo de fitorremediação de Cu, Zn e Mn em colunas de solos cultivados com Jacaranda mimosifolia D. Don, os fungos foram inoculados no solo e na parte aérea das plantas. Todos os tratamentos tiveram 6 repetições e suas médias foram submetidas à análise de variância e teste de média ao nível de 5% de probabilidade. O consórcio fúngico condicionou o crescimento de raízes de soja e milho, aumentou a colonização micorrízica arbuscular em soja e cana-de-açúcar. No jacarandá, os fungos melhoraram o desenvolvimento de raízes e parte aérea, maior acúmulo de Mn e Zn na planta, melhor translocação de Mn e Zn das raízes para a parte aérea, além de diminuir o estresse fisiológico. Além disso, a aplicação conjunta de fungos e biochar nas mudas proporciona proteção à sua atividade fotossintética e reduz o risco ambiental de contaminação por metais por diminuir o total de Cu, Mn e Zn lixiviado. O biochar foi adquirido por meio da pirólise lenta do resíduo do beneficiamento da madeira de eucalipto e aplicado superficialmente no solo. Com isso, esse estudo mostrou que os fungos utilizados apresentam potencial para colaborar com o aumento da produtividade de culturas comerciais e colaborar com a melhoria na remediação de solos contaminados com íons metálicos. The search for sustainable measures to improve and meet the demand for food that population growth requires, combined with the scarcity of productive land, in addition to the excessive accumulation of metals in the environment due to activities such as mining and application of soil fertilizers, were the two problems that motivated the present study. The use of fungi plant growth promoters: Beauveria bassiana, Metarhizium anisopliae, Pochonia chlamydosporia, Purpureocillium lilacinum and Trichoderma asperella can both influence on increasing productivity as the phytoremediation of heavy metals in the soil. These facts are explained by the capacity of the fungal Consortium to synthesize and induce plants to produce phytohormone targeted for the better development of the roots of the host. The further development of roots can stimulate phytoextraction of metals from the soil and give plants tolerance to contamination. In order to evaluate the influence of fungi on the development of plants, were done seed treatments of soybeans and corn and application in aerial part of the culture of sugar cane. To analyze the influence of these organisms in the process of phytoremediation of Cu, Zn and Mn in soil columns cultivated with Jacaranda mimosifolia D. Don, fungi were inoculated in soil and aerial part of plants. All treatments had 6 reptitions and their averages were subjected to analysis of variance and average test at 5% probability. The fungal consortium has conditioned the growth of roots of soybeans and corn, mycorrhizal colonization increased in soybeans and sugar cane. In jacarandá, fungi have improved the development of roots and shoots, greater accumulation of Mn and Zn in plant, best of Mn and Zn translocation from roots to shoots, in addition to decrease physiological stress. In addition, the joint application of fungus and biochar in seedlings provides protection to photosynthetic activity and reduces the risk of environmental contamination by metals by decreasing the amount of Cu, Mn and Zn leached. The biochar was acquired through the slow pyrolysis of the eucalyptus wood processing residue and applied superficially to the soil. With that, this study showed that fungi used present potential to contribute to the increased productivity of commercial crops and contribute to the improvement in the remediation of soils contaminated with metal ions. Dissertação (Mestrado)

Bioremediation concerns the use of plants and microorganisms or their parts, for the decontamination and recuperation of polluted areas. The improvement of the bioremediation techniques is possible due to the last decade advances of the microbiological and biotechnological knowledge and methods. This study aimed to shortly review and discuss the bioremediation of mining areas contaminated with heavy metals focusing in some microbiological and biotechnological techniques. Strategies considered to be important on further studies are also presented.

This study investigated the abilities of pre-processing, feature selection and machine-learning methods for the spectroscopic diagnosis of soil arsenic contamination. The spectral data were pre-processed by using Savitzky-Golay smoothing, first and second derivatives, multiplicative scatter correction, standard normal variate, and mean centering. Principle component analysis (PCA) and the RELIEF algorithm were used to extract spectral features. Machine-learning methods, including random forests (RF), artificial neural network (ANN), radial basis function- and linear function- based support vector machine (RBF- and LF-SVM) were employed for establishing diagnosis models. The model accuracies were evaluated and compared by using overall accuracies (OAs). The statistical significance of the difference between models was evaluated by using McNemar’s test (Z value). The results showed that the OAs varied with the different combinations of pre-processing, feature selection, and classification methods. Feature selection methods could improve the modeling efficiencies and diagnosis accuracies, and RELIEF often outperformed PCA. The optimal models established by RF (OA = 86%), ANN (OA = 89%), RBF- (OA = 89%) and LF-SVM (OA = 87%) had no statistical difference in diagnosis accuracies (Z < 1.96, p < 0.05). These results indicated that it was feasible to diagnose soil arsenic contamination using reflectance spectroscopy. The appropriate combination of multivariate methods was important to improve diagnosis accuracies.

Land use conversion could directly or indirectly influence heavy metal geochemistry by changing soil properties. The aim of this study was to explore the effect of land use conversion on surface soil heavy metal contamination in the karst plateau lakeshore wetlands of Southwest China. Based on this, a total of 120 soil samples were collected from 30 sites from different types of land uses (farmlands, grasslands and woodlands) around a lake in Suohuangcang National Wetland Park in August 2017. Contents of As, Cd, Cu, Cr, Hg, Pb and Zn were analyzed, and soil heavy metal contamination was assessed in all three land use types. Results showed that land use transformation from farmland to grassland or woodland was not conducive to the release of soil heavy metal. Surface soil of all three land use types have been moderately polluted by As, Cr, Pb, and Zn, and grassland and woodland also had moderate Cd contamination. The pollution load index (PLI) results revealed low heavy metal contamination in grassland and woodland but no contamination in farmland. Although the integrated contamination in the studied region did not pose a serious potential ecological risk (RI &lt, 150), it might affect human health through the water supply and food chain. Therefore, it is necessary to monitor and control As, Cd, Cr, Pb, and Zn concentrations of surface soil through controlling pollutants, improving waste treatment, as well as strengthening supervision and management in the vicinity of the Suohuangcang National Wetland Park.

This study was performed to improve the ability to predict the concentrations of Escherichia coli in oyster meat and estuarine waters by using environmental parameters, and microbiological and heavy metal contamination from shellfish growing area in southern Thailand. Oyster meat (n = 144) and estuarine waters (n = 96) were tested for microbiological and heavy metal contamination from March 2016 to February 2017. Prevalence and mean concentrations of E. coli were 93.1% and 4.6 &times, 103 most probable number (MPN)/g in oyster meat, and 78.1% and 2.2 &times, 102 MPN/100 mL in estuarine water. Average 7-day precipitation, ambient air temperature, and the presence of Salmonella were associated with the concentrations of E. coli in oyster meat (p &lt, 0.05). Raw data (MPN/g of oyster meat and MPN/100 mL of estuarine water) and log-transformed data (logMPN/g of oyster meat and logMPN/100 mL of estuarine water) of E. coli concentrations were examined within two contrasting regression models. However, the more valid predictions were conducted using non-log transformed values. These findings indicate that non-log transformed data can be used for building more accurate statistical models in microbiological food safety, and that significant environmental parameters can be used as a part of a rapid warning system to predict levels of E. coli before harvesting oysters.

We monitored heavy metal (As, Cd, Hg, and Pb) concentrations in surface water, sediments, and oligochaetes in four major rivers in Calabria (southern Italy) over the course of 1 year. As, Cd, and Pb showed accumulation factors of 103-105 for water to sediment and 1-10 for sediment to oligochaetes. Hg showed a water to sediment accumulation factor of 10-100. Finally, Hg concentrations exceeded the Italian quality standard for freshwater in all of the rivers, and As concentrations in sediments exceeded the respective Canadian standard. However, the application of an ecological risk assessment method indicated low risks for all monitored rivers. © 2013 Springer Science+Business Media New York.

Heavy metal contamination has caused seriousenvironmental and health-related problems around the world. To identify theconcentrations and sources of heavy metals, 3400 surface soil samples (0-20 cmdepth) were collected from the study area. Subsequently, the concentrations ofCd, Co, Cu, Ni, Pb and Zn in the samples were measured. In order to evaluatenatural or anthropogenic sources of heavy metal content andtheir spatial distribution in agricultural fields ofCentral and East Parts of Black Sea Region soil geostatisticapproach were combined with geographic information system(GIS). GIS technology was employed to produce spatialdistribution maps of the 6 elements in the study area. The results showed that theconcentration of Ni and Co exceeded its threshold level. The local pollutionfrom Ni was attributed to the natural influences. The concentrations of theother heavy metals are relatively lower than the critical values. The meanvalues of the heavy metal contents arranged in the following decreasing order: Ni> Zn > Cu >Pb> Co > Cd in the study area. On the other hand,according to distribution ratio of heavy metals in total soil samples, exceptfor Co and Ni distribution in total soil samples, all other heavy metal elementexceeded concentration in samples were determined about less than 10% totalsoil samples. However, in some regions of the study area, the Cd, Cu and Zncontents were also slightly raised, this case possibly stem from excessive Pfertilization and field traffic.

Background Xiangjiang River (Hunan, China) has been contaminated with heavy metal for several decades by surrounding factories. However, little is known about the influence of a gradient of heavy metal contamination on the diversity, structure of microbial functional gene in sediment. To deeply understand the impact of heavy metal contamination on microbial community, a comprehensive functional gene array (GeoChip 5.0) has been used to study the functional genes structure, composition, diversity and metabolic potential of microbial community from three heavy metal polluted sites of Xiangjiang River. Results A total of 25595 functional genes involved in different biogeochemical processes have been detected in three sites, and different diversities and structures of microbial functional genes were observed. The analysis of gene overlapping, unique genes, and various diversity indices indicated a significant correlation between the level of heavy metal contamination and the functional diversity. Plentiful resistant genes related to various metal were detected, such as copper, arsenic, chromium and mercury. The results indicated a significantly higher abundance of genes involved in metal resistance including sulfate reduction genes (dsr) in studied site with most serious heavy metal contamination, such as cueo, mer, metc, merb, tehb and terc gene. With regard to the relationship between the environmental variables and microbial functional structure, S, Cu, Cd, Hg and Cr were the dominating factor shaping the microbial distribution pattern in three sites. Conclusions This study suggests that high level of heavy metal contamination resulted in higher functional diversity and the abundance of metal resistant genes. These variation therefore significantly contribute to the resistance, resilience and stability of the microbial community subjected to the gradient of heavy metals contaminant in Xiangjiang River. Electronic supplementary material The online version of this article (doi:10.1186/s12866-016-0800-x) contains supplementary material, which is available to authorized users.

Magnetska osjetljivost (MS) je konstanta nedimenzijske proporcionalnosti koja pokazuje stupanj magnetizacije materijala u magnetskom polja. U našem radu, cilj je predviđanje klasifikacije magnetske osjetljivosti tla primjenom algoritama za dubinsko istraživanje podataka (dobivanje korisnih, ranije nepoznatih podataka računarskom analizom velikih baza podataka). Vrijednosti magnetske osjetljivosti ovise o sastavu, veličini zrna magnetičnih minerala i njihovih izvora, litogeničnog, pedogeničnog i antropogeničnog porijekla. U radu smo primijenili dva d klasifikacijska algoritma za dubinsko istraživanje podataka nazvana ID3 i C4.5 za predviđanje vrste MS i stupnja zagađenja u području Izmir u Turskoj. Primjenom algoritama, dobivaju se moguće vrste MS prema vrijednostima koncentracije teških metala (Pb, Cu, Zn, Co, Cd, Ni). Cilj primjene algoritama je izrada dijagrama i pravila za donošenje odluka u svrhu dobivanja vrijednosti MS. Na taj način, eliminiraju se greške nastale promjenom uvjeta okoline i teškoća u mjerenju. Prema tim pravilima, dobili smo uvjete točnosti od 82 % i pokazali da su vrijednosti ispitivanja i vrijednosti mjerenja međusobno kompatibilne., Magnetic susceptibility (MS) is a dimensionless proportionality constant that indicates the degree of magnetization of a material in response to an applied magnetic field. In our study, the focus is to predict the magnetic susceptibility classification of the soil by using data mining algorithms. Magnetic susceptibility values depend on the composition, grain size of magnetic minerals and their source, such as lithogenic, pedogenic and anthropogenic origins. In this paper, we applied two data mining classification algorithms which are called ID3 and C4.5 for predicting MS class and the degree of pollution along the Izmir area in Turkey. By applying the algorithms, possible MS classes are obtained, according to the heavy metal concentration (Pb, Cu, Zn, Co, Cd, Ni) values related to MS. The aim of applying the algorithms is constructing the decision tree and the rules so as to obtain MS values. Thus, errors resulting from the change of ambient conditions and the measurement difficulties are eliminated. According to the rules, we reached 82 % accuracy condition and it is shown that test values and the measurement values are compatible with each other.

O rio Negro, na orla de Manaus, recebe de seus tributários urbanos resíduos domésticos e industriais, cuja composição variada vem modificando as características naturais de suas águas. Com o intuito de avaliar o efeito da ação antrópica sobre o rio Negro foram coletadas amostras de água e analisadas as variáveispH, Eh, condutividade elétrica e alcalinidade (por potenciometria); oxigênio dissolvido (titrimetria); nitrogênio amoniacal e de nitritos (espectrofotometria); os cátions Ca, Mg, Na e K, e os metais Cd, Cu, Cr, Fe, Mn, Ni, Pb e Zn (por espectroscopia de absorção atômica - EAA). Os resultados obtidos para pH, condutividade, oxigênio dissolvido, nitrogênio amoniacal e nitritos mostram piora na qualidade da água do rio Negro, na foz dos igarapés São Raimundo (FISR) e Educandos (FIE) e a jusante destes (JIE), que são os dois maiores tributários urbanos e receptores de esgotos domésticos e efluentes industriais. Os metais predominaram na fase dissolvida e, a maior parte, está acima do limite máximo desejável, preconizado pelo ministério da saúde para águas destinadas ao abastecimento público, exceto cobre e zinco. O estudo mostrou que apesar da contribuição antrópica dos tributários urbanos, o rio Negro mantém, ainda, sua capacidade de diluir os poluentes, principalmente, no período de maior volume de água. The Negro river, on the shoreline of the city of Manaus, receives an input of industrial and domestic wastes from its urban tributaries, which varying composition has been changing the natural characteristics of its waters. Aiming to assess the effect of the human action on the Negro River water samples were collected, and pH, Eh, electric conductivity and alkalinity (by potentiometry); dissolved oxygen (titrimetry); ammonia and nitrite (spectrophotometry); cations Ca, Mg, Na and K, and the metals Cd, Cu, Cr, Fe, Mn, Ni, Pb and Zn (by atomic absorption spectroscopy, AAS) were analyzed. The results for pH, electric conductivity, dissolved oxygen, ammoniacal nitrogen and nitrite values, indicated a worsening water quality in the Negro river, at the mouths of the São Raimundo (FISR) and Educandos (FIE) streams, which are the two major urban tributaries and receptors of domestic wastes and industrial effluents and downstream from them (JIE). Metals predominate in the dissolved phase and, apart from copper and zinc, are mostly above the maximum desirable limit allowed by the Health Ministry for human consumption. This study showed that in spite of the human contribution from its urban tributaries, the Negro river, still maintains its ability for diluting pollutants, mainly during the period of high water.

Background The interaction mechanism between microbial communities and environment is a key issue in microbial ecology. Microbial communities usually change significantly under environmental stress, which has been studied both phylogenetically and functionally, however which method is more effective in assessing the relationship between microbial communities shift and environmental changes still remains controversial. Results By comparing the microbial taxonomic and functional shift pattern along heavy metal contamination gradient, we found that both sedimentary composition and function shifted significantly along contamination gradient. For example, the relative abundance of Geobacter and Fusibacter decreased along contamination gradient (from high to low), while Janthinobacterium and Arthrobacter increased their abundances. Most genes involved in heavy metal resistance (e.g., metc, aoxb and mer) showed higher intensity in sites with higher concentration of heavy metals. Comparing the two shift patterns, there were correlations between them, because functional and phylogenetic β-diversities were significantly correlated, and many heavy metal resistance genes were derived from Geobacter, explaining their high abundance in heavily contaminated sites. However, there was a stronger link between functional composition and environmental drivers, while stochasticity played an important role in formation and succession of phylogenetic composition demonstrated by null model test. Conclusions Overall our research suggested that the responses of functional traits depended more on environmental changes, while stochasticity played an important role in formation and succession of phylogenetic composition for microbial communities. So profiling microbial functional composition seems more appropriate to study the relationship between microbial communities and environment, as well as explore the adaptation and remediation mechanism of microbial communities to heavy metal contamination. Electronic supplementary material The online version of this article (doi:10.1186/s12866-016-0731-6) contains supplementary material, which is available to authorized users.

Measuring the spatial distribution of heavy metal contaminants is the basis of pollution evaluation and risk control. Considering the cost of soil sampling and analysis, spatial interpolation methods have been widely applied to estimate the heavy metal concentrations at unsampled locations. However, traditional spatial interpolation methods assume the sample sites can be located stochastically on a plane and the spatial association between sample locations is analyzed using Euclidean distances, which may lead to biased conclusions in some circumstances. This study aims to analyze the spatial distribution characteristics of copper and lead contamination in river sediments of Daye using network spatial analysis methods. The results demonstrate that network inverse distance weighted interpolation methods are more accurate than planar interpolation methods. Furthermore, the method named local indicators of network-constrained clusters based on local Moran’ I statistic (ILINCS) is applied to explore the local spatial patterns of copper and lead pollution in river sediments, which is helpful for identifying the contaminated areas and assessing heavy metal pollution of Daye.

Thesis (Ph.D. (Environmental Science))--North-West University, Potchefstroom Campus, 2012. Sustainable development and resource efficiency are the common global strategies of the 21st century. The actual global natural resource consumption of humankind went far over the limit and to cover this worldwide resource consumption the productivity of 1.5 earths is now necessary. The work “Reduction of anthropogenic environmental influences by advanced and optimized technologies” discussed the problem of advanced resource efficiencies with mining activities in South Africa as an example. Related strategies to reverse anthropogenic impacts to such an extent that it resembles former natural conditions were also discussed. Heavy metal contaminated soil and water were treated with natural techniques and different natural media to reduce and eliminate contamination and to provide a market value for former unusable material. Specially developed soil ameliorants and natural filter media could increase the total quality of soil and water. Even plants could be established in these changed conditions. Applied to the natural environment an overall upgrade of mining activities could be achieved. To optimize these laboratory and field results support was generated by using evolutionary algorithms as part of the artificial intelligence. By combining applied technologies with the evolution strategy an optimization tool could be developed to simulate, optimize and forecast procedures of anthropogenic impact reversion. With this tool a transfer of solutions to other similar applications in under–developed and developing countries could be shown. The trans–disciplinary scientific approach of balancing the trigger element carbon proved that the reduction to the smallest common element carbon can be used to balance processes and to indicate pollution. As stated in the United Nations Framework, carbon balances are one of the most significant causes of environmental problems, including environmental pollution and health and are also closely related to climate change in general. With carbon balances resource efficiency and resource protection can be transferred into practice. Finally, all results were collected and verified in a decision support system with the aim to optimize the treatment steps and to make the results transparent and available for users in academia and practice. The work was exemplary in showing that the approach of environmental sciences and techniques to reverse anthropogenic interferences back to natural sustainability and evolution, optimized the equilibrium of nature. Doctoral

WOS: 000284683200011, PubMed ID: 20836060, A detailed study was conducted to determine the current status of the heavy metals Cd Cu Cr Fe Hg Mn Ni Pb and Zn in Eskisehir Turkey The 15 different locations (n = 270) studied were specifically selected to identify the effects of soil pollution on the tramway which has been in service since December 2004 for public transportation in Eskisehir The samples were taken from three different lines tramway only lines traffic only lines and both traffic and tramway lines The pollution level was estimated based on the geoaccumulation index (1(geo)) the enrichment factor (EF) the pollution index and the integrated pollution index (IPI) The values for the IPI were in the following order Pb > Zn > Cu > Fe > Mn > Ni > Cr > Cd but mercury was not detected at any sample point These indexes for metals in the soils under consideration correlated with either low or median levels of pollution In addition descriptive statistics were provided for the heavy metals under consideration and box plots were constructed and interpreted for all measured indices Environ Toxicol Chem 2010 29 2720-2725 (C) 2010 SETAC

Marbled teal (Marmaronetta angustirostris) and white-headed duck (Oxyura leucocephala) are the two European ducks threatened with global extinction. We investigated lead (Pb) poisoning in stifftails (Oxyura spp., n = 83) and marbled teal (n = 80) shot or found dead or moribund in Spanish wetlands via gizzard examination and liver, bone, and blood Pb analysis. Ingested Pb shot was present in 32% of shot stifftails and 70 and 43% of dead or moribund stifftails and marbled teal, respectively. Lead- shot ingestion was more frequent in Valencia (eastern Spain), where Pb-shot densities were higher and grit scarcer. Selection of larger grit similar in size to Pb shot may explain the higher rate of Pb-shot ingestion observed in stifftails. Ingested shot was found more frequently in juvenile stifftails than in adults. Lead bone concentrations were higher in ducklings

A field study involving wheat production was extended in order to study the effects of biochar (BC) amendment in paddy soil that had long-term contamination of Cd. The BC was used as an amendment in Cd-contaminated soil for its special property. BC was amended at rates of 10 to 40 t ha-1 during the rice season before rice transplantation in 2009. BC amendments increased soil pH by 0.11 to 0.24 and by 0.09 to 0.24 units, respectively, while the soil CaCl2-extracted Cd was reduced by 10.1% to 40.2% and by 10.0% to 57.0% in 2010 and 2011, respectively. Consequently, the total wheat Cd uptake was decreased by 16.8% to 37.3% and by 6.5% to 28.3%. Wheat grain Cd concentration was reduced by 24.8% to 44.2% and by 14.0% to 39.2% in 2010 and 2011, respectively. The BC application in soil reduced Cd phyto-availability in two wheat seasons possibly by raising soil pH and soil organic carbon (SOC). Therefore, BC may be used for soil remediation, but not to reduce Cd uptake to an adequate level for food production on Cd contaminated soils.

Department of Environmental Science, The University of Burdwan, Golapbag, Burdwan-713 104, West Bengal, India E-mail : banenvs@gmail.com Manuscript received 16 November 2017, revised 24 January 2018, accepted 25 January 2018 The present study focuses on the analysis of industrial wastewater, characterization of agricultural soil and to examine the heavy metal (Pb, Cd, Mn, Zn and Cu) content in some selected vegetables grown on agricultural land receiving untreated wastewater. The unscientific disposal of untreated wastewater has resulted in an accumulation of heavy metals in soils which may not only result in soil contamination, but also lead to elevated metal uptake by vegetables/crops and ultimately affect the food chain. The concentrations (mg/L) of heavy metals in the wastewater samples ranged between Pb : 0.082–0.279, Cd : 0.007– 0.098, Mn : 0.697–0.875, Zn : 0.595–0.887 and Cu : 0.362–0.482. Average metal concentration in untreated wastewater was in the sequence of Mn > Zn > Cu > Pb > Cd, wastewater irrigated contaminated soil also followed the same sequence though BCF followed the sequence of Cd > Mn > Zn > Pb > Cu. The high concentration of Cd was found in Phaseolus vulgaris (9.865 mg/kg) with its bioconcentration factor (BCF) value (3.446) followed by Pisum sativum (Ave. : 9.742 mg/kg; BCF : 3.403) and Spinacia oleracea (Ave. : 9.241 mg/kg; BCF: 3.228). High level of metal concentrations was also observed in the other vegetables analyzed. This may be due to the accumulation of heavy metals in the agricultural soil due to long-term irrigation. The higher values of metal concentration and BCF indicated heavy metal contamination in the wastewater irrigated site that is may creates a major threat of negative impact on human health.

Lead, cadmium, mercury and arsenic are the most important heavy metals which may cause health risks following consumption of contaminated foods. Table salt is one the mostly used food additive with unique place in food consumption. Although purified table salt is expected to have lower level of contamination, some Iranians still prefer to use rock salt. Use of rock salt for food purposes has been banned by Iranian health authorities. In this study, heavy metal contamination of table salt consumed in Iran has been investigated. One hundred samples of rock and refined table salts were analyzed using atomic absorption spectrophotometeric methods for the presence of toxic heavy metals. The mean concentration of tested tracer metals including Cd, Pb, Hg and As was 0.024, 0.438, 0.021 and 0.094 μg/g, respectively. The concentrations of tested heavy metals were well below the maximum levels set by Codex. However, no statistically significant difference was found between contamination of rock salt and refined salt to heavy metals.