Suitability of using diffusive gradients in thin films (DGT) to study metal bioavailability in mine tailings: possibilities and constraints

Background, aim, and scope  

Diffusive gradients in thin films (DGT) have been recognized as a suitable tool to assess in situ metal bioavailability in soils. Mine tailings have some singular characteristics such as high heavy-metal concentrations, low pH, or absence of water retention capacity that may compromise the correct application of this technique whose applicability is known to be pH dependent. The goal of this study was to determine the response of DGT devices in heavy-metal-polluted mine tailings with different pH. In addition some experiments were performed in order to determine the effect of acidic pH and dissolved ions on the binding properties of the chelating resin.     

Effect of factors on decolorization of azo dye methyl orange by oxone/natural sunlight in aqueous solution

Purpose  

The oxone process for azo dye decolorization has drawbacks such as difficulties with reuse, risks of secondary pollution, and high costs associated with UV irradiation. This study aims to explore the use of oxone for decolorization in the absence of catalyst and under natural sunlight conditions (i.e., oxone/natural sunlight system) and evaluate the impacts of operating parameters (reagent dosage, initial methyl orange (MO) concentration, and initial pH) and coexisting substances (humic acid, NO₃⁻, metal ions) on the system’s decolorization efficiency.     

Effluent characterization and different modes of reuse in agriculture—a model case study

Background, aim, and scope  

High-quality waters are steadily retreating worldwide. Discharge of industrial effluent in the environment again declines soil/water quality to a great extent. On the other hand, effluent reuse in agriculture could be a means to conserve natural resources by providing assured water supply for growing crops. But industrial effluents are highly variable in nature, containing a variety of substances, and all are not favorable for farming. Appraisal and developing modes of effluent reuse is therefore a prerequisite to enable its proper use in agriculture. Effluents of various industries were assessed and approaches for their use in farming were developed for a particular region in this study. As per availability of effluents, the same could be implemented in other water-scarce areas.     

Major and trace elements in soils in the Central Pyrenees: high altitude soils as a cumulative record of background atmospheric contamination over SW Europe

Background, aim, and scope  

High mountain soils constitute a long-term cumulative record of atmospherically deposited trace elements from both natural and anthropogenic sources. The main aims of this study were to determine the level of major and trace metals (Al, Ti, Mn, Fe, and Zr) of lithologic origin and airborne contaminating trace elements (Ni, Cu, Zn, As, Cd, and Pb) in soils in the Central Pyrenees as an indication of background contamination over SW Europe, to establish whether there is a spatial pattern of accumulation of trace elements in soils as a function of altitude, and to examine whether altitude-related physicochemical properties of soils affect the accumulation of major metals and trace elements.     

Influence of linear alkylbenzene sulfonate (LAS) on the structure of Alphaproteobacteria,Actinobacteria, and Acidobacteria communities in a soil microcosm

Background, aim, and scope  

Linear alkylbenzene sulfonate (LAS) is the most used anionic surfactant in a worldwide scale and is considered a high-priority pollutant. LAS is regarded as a readily biodegradable product under aerobic conditions in aqueous media and is mostly removed in wastewater treatment plants, but an important fraction (20–25%) is immobilized in sewage sludge and persists under anoxic conditions. Due to the application of the sludge as a fertilizer, LAS reaches agricultural soil, and therefore, microbial toxicity tests have been widely used to evaluate the influence of LAS on soil microbial ecology. However, molecular-based community-level analyses have been seldom applied in studies regarding the effects of LAS on natural or engineered systems, and, to our knowledge, there are no reports of their use for such appraisals in agricultural soil. In this study, a microcosm system is used to evaluate the effects of a commercial mixture of LAS on the community structure of Alphaproteobacteria, Actinobacteria, and Acidobacteria in an agricultural soil.     

EU Water Framework Directive and Stockholm Convention

Background, aim and scope

Water is a renewable resource and acceptable quality is important for human health, ecological and economic reasons, but human activity can cause great damage to the natural aquatic environment. Managing the water cycle in a sustainable way is the key to protect natural resources and human health. On a global level, the microbiological contamination of water sources is a major problem in connection with poverty and the United Nations Millennium Development Declaration is an important initiative to handle this problem. In terms of environmental health, persistent organic pollutants (POPs) circulate globally; as they travel long distances, they are found in remote areas far from their original source of application and can cause damage wherever they move to. On a global scale, United Nations Environmental Programme (UNEP) issued the Stockholm Convention to reduce POPs; in the European Union (EU), one intention of the Water Framework Directive (WFD) is to reach the good chemical status of waters; beside these regulations, there are other directives in support of these goals. The aim of this paper is to discuss whether the Stockholm Convention and the WFD allows meeting the targets of protection of human and environmental health, which are established in the different directives and how could we approach the targets.

Materials and methods

The aims and scopes of different directives are compiled and compared with the actual quality of water, different approaches of standard settings are compared and potential treatment options are discussed.

Results

Under the Stockholm Convention on POPs, which came into force in May 2004, governments are required to develop a National Implementation Plan (NIP) setting out how they will address their obligations under the convention and how they will take measures to eliminate or reduce the release of POPs into the environment by the use of best available techniques (BAT) and application of best environmental practices (BEP). On a European level, the WFD has been in place as the main European legislation to protect our water resources and the water environment of Europe since 2000. It requires managing river basins so that the quality and quantity of water does not affect the ecological services of any specific water body. Nevertheless, the goals of other directives as for drinking water, bathing water and urban wastewater treatment are not yet harmonised mainly concerning microbiological, priority substances and priority hazardous substances (PS/PHS) contamination. Following the detection of substances, a risk assessment with sound effect data needs to be performed also for regulatory decisions and priorisation of measures to remove emerging contaminants. Beside personal care products and industrial contaminants, faecal pollution of recreational waters is one of the major hazards facing users, although microbial contamination from other sources as well as chemical and physical aspects also affects the suitability of water for recreation. As in arid and semiarid areas, wastewater is considered for irrigation with regulatory needs of hygienic and chemical parameters—health-based targets—to avoid the contamination of crops and food. In surface waters, currently, the relationships between physical and chemical properties and the biological state of surface waters were quite well-understood to enable the management of catchments and rivers to achieve ecological quality.

Discussion

Nevertheless, more work is needed to find out the actual impact of the regulations for single chemicals and complex mixtures, in terms of environmental quality standards to achieve a ‘good chemical status’, on the good biological status. In a next step after the adoption of the list of PS/PHS substances, which also includes the POPs, the Urban Wastewater Treatment Directive (UWWTD) needs to be adjusted and existing or new treatment options (BATs) should comply with the new requirements of the different directives.

Conclusions

Relevant substances threaten human health and the environment by new effects such as CMR, endocrine-disrupting effects or neurotoxicity which are not yet considered in an adequate way by assessment methods and regulatory standards and the application of abatement technologies. The Registration, Evaluation, Authorisation and Restriction of Chemicals helps to control the sources, but WFD, the Stockholm Convention and UWWTD need to be harmonised and a rolling revision process should react on new developments. Finally, to answer the question if the Stockholm Convention and the WFD (2000/60/EC) could reach the target—I would state that they provide a very valuable frame to approach the targets, but there is still way to go to reach them on an EU level and on a global scale, also under the aspects of the Stockholm Convention and the Millennium Development Goals.

Perspectives

The compilation of the goals of different regulations and combined actions will save a lot of administrative efforts and money.

     

Assessment of successful experiments and limitations of phytotechnologies: contaminant uptake, detoxification and sequestration, and consequences for food safety

Purpose  

The term “phytotechnologies” refers to the application of science and engineering to provide solutions involving plants, including phytoremediation options using plants and associated microbes to remediate environmental compartments contaminated by trace elements (TE) and organic xenobiotics (OX). An extended knowledge of the uptake, translocation, storage, and detoxification mechanisms in plants, of the interactions with microorganisms, and of the use of “omic” technologies (functional genomics, proteomics, and metabolomics), combined with genetic analysis and plant improvement, is essential to understand the fate of contaminants in plants and food, nonfood and technical crops. The integration of physicochemical and biological understanding allows the optimization of these properties of plants, making phytotechnologies more economically and socially attractive, decreasing the level and transfer of contaminants along the food chain and augmenting the content of essential minerals in food crops. This review will disseminate experience gained between 2004 and 2009 by three working groups of COST Action 859 on the uptake, detoxification, and sequestration of pollutants by plants and consequences for food safety. Gaps between scientific approaches and lack of understanding are examined to suggest further research and to clarify the current state-of-the-art for potential end-users of such green options.     

Is phytoremediation a sustainable and reliable approach to clean-up contaminated water and soil in Alpine areas?

Background, aim and scope  

Phytoremediation does exploit natural plant physiological processes and can be used to decontaminate agricultural soils, industrial sites, brownfields, sediments and water containing inorganic and organic pollutants or to improve food chain safety by phytostabilisation of toxic elements. It is a low-cost and environment friendly technology targetting removal, degradation or immobilisation of contaminants. The aim of the present review is to highlight some recent advances in phytoremediation in the Alpine context.     

The effect of continuous exposure of copper on the properties and extracellular polymeric substances (EPS) of bulking activated sludge

Introduction  

This study investigated the effect of copper on chemical oxygen demand (COD) removal efficiency and on the properties (mainly settling and dewatering) and the composition of extracellular polymeric substances (EPS) when 20 mg/L Cu(II) was continuously dosed to a sequencing batch reactor (SBR) inoculated with activated sludge.     

Factors that have an effect on degradation of diclofenac in aqueous solution by gamma ray irradiation

Purpose  

Gamma ray irradiation is considered as an effective way to degrade diclofenac. However, due to the extensive coexisting substances in natural waters, the use of gamma ray irradiation for degradation is often influenced by multiple factors. The various factors that affect degradation efficiency, such as initial diclofenac concentration, initial pH, and the concentration of the additives including H₂O₂ (·OH radical promoter), CH₃OH (·OH radical scavenger), thiourea (·OH, H·, and e_aq⁻ scavenger), humic acid, and NO₃⁻ (coexisting substances in natural waters), are investigated. Furthermore, possible intermediate products are identified and corresponding transformation pathways are proposed.     

In situ stabilization of trace metals in a copper-contaminated soil using P-spiked Linz-Donawitz slag

Purpose  

A former wood exploitation revealing high Cu and As concentration of the soils served as a case study for assisted phytoextraction.     

Evaluation of environmental magnetic pollution screening in soils of basaltic origin: results from Nashik Thermal Power Station, Maharashtra, India

Background, aim, and scope

Soils of basaltic origin cause difficulties in environmental magnetic screening for heavy metal pollution due to their natural high background values. Magnetic parameters and heavy metal content of highly magnetic topsoils from the Deccan Trap basalts are investigated to assess their potential for use in environmental magnetic pollution screening. This work extends the fast and cost-effective magnetic pollution screening techniques into soils with high natural magnetic signals.

Materials and methods

Fifty-five topsoil samples from N?CS and W?CE transects were collected and subdivided according to grain size using wet sieving technique. Magnetic susceptibility, soft isothermal remanent magnetization (Soft IRM), thermomagnetic analysis, scanning electron microscopy (SEM), and heavy metal analysis were performed on the samples.

Results

Magnetic analyses reveal a significant input of anthropogenic magnetic particulate matter within 6 km of the power plant and the adjacent ash pond. Results depend strongly on the stage of soil development and vary spatially. While results in the W, E, and S directions are easily interpretable, in the N direction, the contribution of the anthropogenic magnetic matter is difficult to assess due to high magnetic background values, less developed soils, and a more limited contribution from the fly ash sources. Prevailing winds towards directions with more enhanced values seem to have a certain effect on particulate matter accumulation in the topsoil. Thermomagnetic measurements show Verwey transition and Hopkinson peak, thus proving the presence of ferrimagnetic mineral phases close to the pollution source. A quantitative decrease of the anthropogenic ferrimagnetic mineral concentration with increased distance is evident in Soft IRM measurements. SEM investigations of quantitatively extracted magnetic particles confirm the fly ash distribution pattern obtained from the magnetic and heavy metal analyses. Evaluation of magnetic and chemical data in concert with the Pollution Load IndiceS (PLIS) of Pb, Zn, and Cu reveals a good relationship between magnetic susceptibility and the metal content.

Conclusions

Integrated approaches in data acquisition of magnetic and chemical parameters enable the application of magnetic screening methods in highly magnetic soils. Combined data evaluation allows identification of sampling sites that are affected by human activity, through the deviation of the magnetic and chemical data from the general trend. It is shown that integrative analysis of magnetic parameters and a limited metal concentration dataset can enhance the quality of the output of environmental magnetic pollution screening significantly.     

Quantifying phosphorus levels in soils, plants, surface water, and shallow groundwater associated with bahiagrass-based pastures

Background, aim, and scope  

Recent assessments of water quality status have identified eutrophication as one of the major causes of water quality ‘impairment’ not only in the USA but also around the world. In most cases, eutrophication has accelerated by increased inputs of phosphorus due to intensification of crop and animal production systems since the early 1990s. Despite substantial measurements using both laboratory and field techniques, little is known about the spatial and temporal variability of phosphorus dynamics across landscapes, especially in agricultural landscapes with cow-calf operations. Critical to determining environmental balance and accountability is an understanding of phosphorus excreted by animals, phosphorus removal by plants, acceptable losses of phosphorus within the manure management and crop production systems into soil and waters, and export of phosphorus off-farm. Further research effort on optimizing forage-based cow-calf operations to improve pasture sustainability and protect water quality is therefore warranted. We hypothesized that properly managed cow-calf operations in subtropical agroecosystem would not be major contributors to excess loads of phosphorus in surface and ground water. To verify our hypothesis, we examined the comparative concentrations of total phosphorus among soils, forage, surface water, and groundwater beneath bahiagrass-based pastures with cow-calf operations in central Florida, USA.     

Estrogenic effects of dissolved organic matter and its impact on the activity of 17β-estradiol

Background and purpose  

The ubiquitous dissolved organic matter (DOM) is actually not inert as we always think, and the hormone-like effects of DOM have been reported. The objective of this study was to investigate the estrogenic effects of DOM and its impact on the activity of the natural estrogen 17β-estradiol (E2).     

The bioaccumulation and translocation of Fe,Zn, and Cu in species of mushrooms from <Emphasis Type="Italic">Russula</Emphasis> genus

Introduction  

Many previous studies revealed a high ability of mushrooms to accumulate heavy metals from environment. This paper concerns the capacity of some wild macromycetes belonging to Russula genus to accumulate heavy metals in natural condition of pH (between 6.5 and 6.8) and the pattern of metal translocation in the fruiting body.     

Chemometric evaluation for the relation of BCR sequential extraction method and in vitro gastro-intestinal method for the assessment of metal bioavailability in contaminated soils in Turkey

Introduction  

A chemometric evaluation has been done to classify metal ions in soils and to determine whether or not the gastric and intestinal phases of a physiologically based extraction test bear any relation to any of the phases of the four-stage Community Bureau of Reference (BCR) extraction protocol.     

Microbial biomass carbon and enzyme activities of urban soils in Beijing

Introduction  

To promote rational and sustainable use of soil resources and to maintain the urban soil quality, it is essential to assess urban ecosystem health. In this study, the microbiological properties of urban soils in Beijing and their spatial distribution patterns across the city were evaluated based on measurements of microbial biomass carbon and urease and invertase activities of the soils for the purpose of assessing the urban ecosystem health of Beijing.     

Column studies to investigate the fate of veterinary antibiotics in clay soils following slurry application to agricultural land

The environment may be exposed to veterinary medicines administered to livestock due to the application of organic fertilisers to land. For other groups of substances that are applied to agricultural land (e.g. pesticides), preferential flow in underdrained clay soils has been identified as an extremely important pathway by which pollution of surface waters can occur. Three soil column leaching experiments have therefore been carried out using a clay soil to investigate the fate of a range of antibiotics from the sulphonamide, tetracycline and macrolide groups. These column studies complemented a range of other experiments at the field and semi-field scales, as well as modelling studies which are being reported in separate papers. Each column study had a different objective. The first examined the effect of pig slurry on the mobility of antibiotics in clay loam soil. The second experiment investigated changes in soil water pH due to the application of slurry. The final experiment quantified the extent to which soil tillage prior to slurry application can reduce the leaching of antibiotic residues found in slurry. It was found that slurry had no impact on the leaching of oxytetracycline although soil water pH was affected significantly by slurry application. It was also shown that pre-tillage can substantially reduce the leaching of antibiotic residues through macroporous clay soils.     

In vitro gastro-intestinal method for the assessment of heavy metal bioavailability in contaminated soils

Introduction  

Balya and its associated villages which is a town of the Balikesir region of Turkey have very rich zinc, lead, and manganese mines. These mines have been operating since the thirteenth century and now there is heavy metal contamination in both the soil and natural waters in these areas.     

PCDD/F and dioxin-like PCB profiles in soils amended with sewage sludge,compost, farmyard manure,and mineral fertilizer since 1962

Background, aim, and scope  

Biowaste contains compounds of agricultural value such as organic carbon, nutrients, and trace elements and can partially replace mineral fertilizer (MIN) and improve the physical properties of the soil. However, the obvious benefits of land spreading need to be carefully evaluated against potential adverse effects on the environment and human health. Environmental contamination resulting from biowaste application is one of the key variables when assessing cost/benefits. This study provides data on the resulting concentration of polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) in the soil column as a result of the different types of fertilizers.