Archive for the ‘Hot Articles’ Category

Free access to HOT articles

These HOT articles were recommended by our referees and are free to access for 4 weeks*

Bayesian uncertainty assessment of a semi-distributed integrated catchment model of phosphorus transport
Jostein Starrfelt and Øyvind Kaste
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00619K, Paper

Graphical abstract: Bayesian uncertainty assessment of a semi-distributed integrated catchment model of phosphorus transport

Blending remote sensing data products to estimate photochemical production of hydrogen peroxide and superoxide in the surface ocean
Leanne C. Powers and William L. Miller
Environ. Sci.: Processes Impacts, 2014,16, 792-806
DOI: 10.1039/C3EM00617D, Paper

Graphical abstract: Blending remote sensing data products to estimate photochemical production of hydrogen peroxide and superoxide in the surface ocean

Wavelength and temperature-dependent apparent quantum yields for photochemical formation of hydrogen peroxide in seawater
David J. Kieber, Gary W. Miller, Patrick J. Neale and Kenneth Mopper
Environ. Sci.: Processes Impacts, 2014,16, 777-791
DOI: 10.1039/C4EM00036F, Paper

Graphical abstract: Wavelength and temperature-dependent apparent quantum yields for photochemical formation of hydrogen peroxide in seawater

Modelling phosphorus loading and algal blooms in a Nordic agricultural catchment-lake system under changing land-use and climate
Raoul-Marie Couture, Koji Tominaga, Jostein Starrfelt, S. Jannicke Moe, Øyvind Kaste and Richard F. Wright
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00630A, Paper

Graphical abstract: Modelling phosphorus loading and algal blooms in a Nordic agricultural catchment-lake system under changing land-use and climate

Association of nuisance filamentous algae Cladophora spp. with E. coli and Salmonella in public beach waters: impacts of UV protection on bacterial survival
Aubrey Beckinghausen, Alexia Martinez, David Blersch and Berat Z. Haznedaroglu
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00659J, Paper

Graphical abstract: Association of nuisance filamentous algae Cladophora spp. with E. coli and Salmonella in public beach waters: impacts of UV protection on bacterial survival

Degradation of organic pollutants in/on snow and ice by singlet molecular oxygen (1O*2) and an organic triplet excited state
Jonathan P. Bower and Cort Anastasio
Environ. Sci.: Processes Impacts, 2014,16, 748-756
DOI: 10.1039/C3EM00565H, Paper

Graphical abstract: Degradation of organic pollutants in/on snow and ice by singlet molecular oxygen (1O*2) and an organic triplet excited state

Estimating hydroxyl radical photochemical formation rates in natural waters during long-term laboratory irradiation experiments
Luni Sun, Hongmei Chen, Hussain A. Abdulla and Kenneth Mopper
Environ. Sci.: Processes Impacts, 2014,16, 757-763
DOI: 10.1039/C3EM00587A, Paper

Graphical abstract: Estimating hydroxyl radical photochemical formation rates in natural waters during long-term laboratory irradiation experiments

The importance of charge-transfer interactions in determining chromophoric dissolved organic matter (CDOM) optical and photochemical properties
Charles M. Sharpless and Neil V. Blough
Environ. Sci.: Processes Impacts, 2014,16, 654-671
DOI: 10.1039/C3EM00573A, Critical Review

Graphical abstract: The importance of charge-transfer interactions in determining chromophoric dissolved organic matter (CDOM) optical and photochemical properties

A critical assessment of the photodegradation of pharmaceuticals in aquatic environments: defining our current understanding and identifying knowledge gaps
Jonathan K. Challis, Mark L. Hanson, Ken J. Friesen and Charles S. Wong
Environ. Sci.: Processes Impacts, 2014,16, 672-696
DOI: 10.1039/C3EM00615H, Critical Review

Graphical abstract: A critical assessment of the photodegradation of pharmaceuticals in aquatic environments: defining our current understanding and identifying knowledge gaps

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Grazing the surface of agricultural effects on water quality – impacts of in-stream cattle activity

The presence of cattle in close proximity to water courses can influence pollution levels in both direct and in-direct means. This study by researchers at Lancaster University reveals how these impacts can be best understood using simultaneous monitoring of both physical movement of cattle and water quality parameters.

Livestock farming in close proximity to streams can influence water quality in numerous ways. For example enhanced bank-side erosion and removal of vegetation can result in mobilization of sediments into water courses and increase turbidity. However, uncertainty exists regarding the extent to which the physical movement of cattle into and within the stream bed influences sediment resuspension and contribute to water quality degradation.

Previous studies assessing in-stream cattle impacts have focussed on short-term controlled events and often do not differentiate between bank-side and in-stream activity. The irregular behaviour of cattle means there is a need for high–frequency and simultaneous monitoring of cattle in-stream movement and water quality parameters over  sufficiently long periods.  This investigation by Julie Terry and co-workers at the Lancaster Environment Centre, UK attempts to assess the temporal relationship between physical in-stream activity of cattle and the level water quality.

This study investigated the physical movement of cattle in a stream and the impacts on suspended solid concentration (SSC) and observing a ‘signal response’ in an unfenced stretch of river in Cumbria, north-west England over a 4 month period. This involved the use of high resolution monitoring data derived using motion capture camera surveillance, taking over 31,000 images. At the same time, high resolution water quality data including turbidity (converted to SSC), water level and flow rate were also monitored.

It was shown that for the days when cattle were grazing nearby, of the instances that SSC exceeded 25 mg/l (the Freshwater Fish Directive guidance threshold), 58% could be attributed to the presence of cattle. However, only 3.6% of total sediment load in the stream was directly caused by cattle in-stream activity. Flow is still the main factor influencing total sediment transported, with cattle contributing a much smaller proportion. No relationship was noted between SSC response and absolute number of cattle feet in the water, attributed to the episodic nature of cattle-related sediment disturbances and the variability in stream flow.

Hysteresis analysis (modelling the relationship between concentration levels and discharge) demonstrated a lag time between the presence of cows in the stream and a critical amount of their contribution to SSC  with a reoccurring ‘first-flush’ of sediment created from non-cattle activity.  It was indicted, however that cattle can also provide considerable contribution indirectly e.g. due to erosion of stream banks.

Don’t let this work go in one ear and out the udder. It demonstrates the impact cattle can have on water quality in unprotected and unmonitored stretches of river and indicates the need for best practice measures for livestock management need to be adhered to closely in order to reduce maintain the ecological status of water courses. The authors have demonstrated the need for high-resolution monitoring data is to best understand and mitigate against these dangers and also outline directions for further work to compliment these results.

To access the full HOT Article for free*, click the link below:

Temporal dynamics between cattle in-stream presence and suspended solids in a headwater catchment
Julie A. Terry, Clare McW.H. Benskin, Emma F. Eastoe and Philip M. Haygarth
Environ. Sci.: Processes Impacts, 2014,
DOI: 10.1039/C3EM00686G

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Free access to HOT articles

These HOT articles were recommended by our referees and are free to access for 4 weeks*

Assessing the effect of phosphate and silicate on Cd bioavailability in soil using an Escherichia coli cadAp::luc-based whole-cell sensor
Qi-Hui Hou, An-Zhou Ma, Ye Li, Xu-Liang Zhuang, Zhi-Hui Bai, Xin-Ke Zhang and Guo-Qiang Zhuang  
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00598D, Paper

Graphical abstract: Assessing the effect of phosphate and silicate on Cd bioavailability in soil using an Escherichia coli cadAp::luc-based whole-cell sensor
Insights into the complete and partial photooxidation of black carbon in surface waters
Collin P. Ward, Rachel L. Sleighter, Patrick G. Hatcher and Rose M. Cory  
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00597F, Paper

Graphical abstract: Insights into the complete and partial photooxidation of black carbon in surface waters
Temporal dynamics between cattle in-stream presence and suspended solids in a headwater catchment
Julie A. Terry, Clare McW.H. Benskin, Emma F. Eastoe and Philip M. Haygarth  
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00686G, Paper

Graphical abstract: Temporal dynamics between cattle in-stream presence and suspended solids in a headwater catchment
Outdoor passive air monitoring of semi volatile organic compounds (SVOCs): a critical evaluation of performance and limitations of polyurethane foam (PUF) disks
P. Bohlin, O. Audy, L. Škrdlíková, P. Kukučka, P. Přibylová, R. Prokeš, Š. Vojta and J. Klánová  
Environ. Sci.: Processes Impacts, 2014,16, 433-444
DOI: 10.1039/C3EM00644A, Paper

Graphical abstract: Outdoor passive air monitoring of semi volatile organic compounds (SVOCs): a critical evaluation of performance and limitations of polyurethane foam (PUF) disks
Photometric hydroxyl radical scavenging analysis of standard natural organic matter isolates
J. E. Donham, E. J. Rosenfeldt and K. R. Wigginton  
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00663H, Paper

Graphical abstract: Photometric hydroxyl radical scavenging analysis of standard natural organic matter isolates

Remedy performance monitoring at contaminated sediment sites using profiling solid phase microextraction (SPME) polydimethylsiloxane (PDMS) fibers
Courtney Thomas, David Lampert and Danny Reible  
Environ. Sci.: Processes Impacts, 2014,16, 445-452
DOI: 10.1039/C3EM00695F, Paper

Graphical abstract: Remedy performance monitoring at contaminated sediment sites using profiling solid phase microextraction (SPME) polydimethylsiloxane (PDMS) fibers
Cluster analysis of passive air sampling data based on the relative composition of persistent organic pollutants
Xiande Liu and Frank Wania  
Environ. Sci.: Processes Impacts, 2014,16, 453-463
DOI: 10.1039/C3EM00605K, Paper

Graphical abstract: Cluster analysis of passive air sampling data based on the relative composition of persistent organic pollutants

Critical review of electrochemical advanced oxidation processes for water treatment applications
Brian P. Chaplin  
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00679D, Critical Review

Graphical abstract: Critical review of electrochemical advanced oxidation processes for water treatment applications
 
Kinetics of heterogeneous reactions of ozone with representative PAHs and an alkene at the air–ice interface at 258 and 188
K D. Ray, H. Lišková and P. Klán  
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00665D, Paper

Graphical abstract: Kinetics of heterogeneous reactions of ozone with representative PAHs and an alkene at the air–ice interface at 258 and 188 K

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Free access to HOT articles!

These HOT articles were recommended by our referees and are free to access for 4 weeks*

The role of indirect photochemical degradation in the environmental fate of pesticides: a review
Christina K. Remucal
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00549F, Critical Review 

Automated method for determining the flow of surface functionalized nanoparticles through a hydraulically fractured mineral formation using plasmonic silver nanoparticles
Samuel J. Maguire-Boyle, David J. Garner, Jessica E. Heimann, Lucy Gao, Alvin W. Orbaek and Andrew R. Barron
Environ. Sci.: Processes Impacts, 2014,16, 220-231
DOI: 10.1039/C3EM00718A, Paper 

Elevated risk from estrogens in the Yodo River basin (Japan) in winter and ozonation as a management option
Vimal Kumar, Seiya Hanamoto, Andrew C. Johnson, Naoyuki Yamashita, Norihide Nakada and Hiroaki Tanaka
Environ. Sci.: Processes Impacts, 2014,16, 232-238
DOI: 10.1039/C3EM00219E, Paper 

Evaluation of DGT as a long-term water quality monitoring tool in natural waters; uranium as a case study
Geraldine S. C. Turner, Graham A. Mills, Michael J. Bowes, Jonathan L. Burnett, Sean Amos and Gary R. Fones
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00574G, Paper 

Nanoscale zero-valent iron (nZVI) for the treatment of concentrated Cu(II) wastewater: a field demonstration
Shaolin Li, Wei Wang, Weile Yan and Wei-xian Zhang
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00578J, Paper

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Bio-cathodes : powering towards clean water, energy and biomass production

The use of passive biocathodes could potentially hold the key to producing an environmentally sustainable approach for achieving combined waste water treatment and water desalinization, researchers at Mississippi State University have indicated.

Current world population now exceeds 7 billion. As this number continues to grow, so does the demand for fresh water resources. Ensuring access to clean water supplies is now a major priority across the planet. A key factor governing this is the approach taken to achieve effective wastewater treatment and water desalination.

Wastewater treatment is commonly achieved through activated sludge treatment utilising biochemical reaction and physical separation, while desalination can be achieved through thermal evaporation or membrane separation. However, both of these approaches are intensive in terms of cost and energy usage and also emit CO2. There is a need to develop methods where external energy consumption is minimized and energy recovery can be optimized.

Microbial desalination cells (MDCs) are a recent technological innovation where simultaneous wastewater treatment and desalination are achieved. In such bioelectrochemical cells, chemical catholytes such as ferricyanide are commonly used. However, these are not suitable for large-scale usage due to the prohibitive cost, large energy demands and environmental toxicity issues.

Another option is to use air-cathodes, which utilize oxygen as a thermal electron acceptor. However, these can suffer from slower redox kinetics, requiring the use of expensive catalysts, and large energy requirements to maintain aeration levels. A more sustainable and financially viable approach could therefore be to use biological cathodes, which utilise microorganisms as biocatalysts.


In this study by Bahareh Kokabian and Veera Gnaneswar Gude, which featured as the cover article for Issue 12, Vol 15 of ESPI, the performance of an MDC with a conventional air-cathode and a photosynthetic microbial desalination cell (PMDC) utilising the microalgae Chlorella vulgaris were evaluated for their performance in terms of COD removal, desalination and energy generation from sewage sludge. This represents the first study of its kind to be attempted.

Fig 1. Schematic of the photosynthetic microbial desalination cell system with algal biocathode

The results indicate that PMDCs can perform better than air-cathodes and as well as other conventional MDCs. COD removal of 66% and 57% were measured for the PMDC and air-cathode MDC respectively. Desalination rates were also enhanced, with levels of 40% measured for the PMDC and 24% for the air-cathode MDC.

Maximum voltage produced was higher for the PMDC (0.236 V) than for the air-cathode MDC (0.219 V). Moreover, the PMDC produces longer, more stable voltage, unlike conventional cathodes where potential reduction occurs after a time. Furthermore, it was shown that only 55% of the cathode volume was utilised, indicating that power production and desalination rates could be further improved if the MDC reactor design and electrode/material configuration are optimized.


Algae biocathodes in PMDCs provide the advantage of a continuous supply of electron acceptors and omit the need for additional chemical transport, storage, dosing, and post-treatment. The biochemical nature of the process also means the wastewater is essentially treated as a growth medium, producing valuable algal biomass, which could be used to obtain constructive products such as biogas, biohydrogen and biofuels.

This study therefore demonstrates that the use of PMDCs can provide an environmentally benign approach to wastewater treatment in which algae act as an in situ generator of oxygen. This has the potential to be beneficial in enhancing environmental and economic sustainability of water treatment whilst helping to improve COD removal, desalination and energy recovery in the same process.


This HOT paper is available to download through the following link:
Photosynthetic microbial desalination cells (PMDCs) for clean energy, water and biomass production, Bahareh Kokabian and Veera Gnaneswar Gude. DOI: 10.1039/c3em00415e

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Free to access HOT articles!

These HOT articles were recommended by our referees and are free to access for 4 weeks*

Priority organic compounds in wastewater effluents from the Mediterranean and Atlantic basins of Andalusia (Spain)
Nieves Barco-Bonilla, Roberto Romero-González, Patricia Plaza-Bolaños, José Luis Martínez Vidal, Antonio J. Castro, Isabel Martín, Juan José Salas and Antonia Garrido Frenich  
Environ. Sci.: Processes Impacts, 2013,15, 2194-2203
DOI: 10.1039/C3EM00329A, Paper

Graphical abstract: Priority organic compounds in wastewater effluents from the Mediterranean and Atlantic basins of Andalusia (Spain)
Photosynthetic microbial desalination cells (PMDCs) for clean energy, water and biomass production
Bahareh Kokabian and Veera Gnaneswar Gude  
Environ. Sci.: Processes Impacts, 2013,15, 2178-2185
DOI: 10.1039/C3EM00415E, Paper

Graphical abstract: Photosynthetic microbial desalination cells (PMDCs) for clean energy, water and biomass production

Environmental specimen banks as a resource for mercury and mercury isotope research in marine ecosystems
Rusty D. Day, Paul R. Becker, Olivier F. X. Donard, Rebecca S. Pugh and Stephen A. Wise  
Environ. Sci.: Processes Impacts, 2014,16, 10-27
DOI: 10.1039/C3EM00261F, Perspective

Graphical abstract: Environmental specimen banks as a resource for mercury and mercury isotope research in marine ecosystems

Effects of pretreatment on the denaturation and fragmentation of genomic DNA for DNA hybridization
Xiaofang Wang and Ahjeong Son  
Environ. Sci.: Processes Impacts, 2013,15, 2204-2212
DOI: 10.1039/C3EM00457K, Paper

Graphical abstract: Effects of pretreatment on the denaturation and fragmentation of genomic DNA for DNA hybridization

Neutral polyfluoroalkyl substances in the global Atmosphere
A. Gawor, C. Shunthirasingham, S. J. Hayward, Y. D. Lei, T. Gouin, B. T. Mmereki, W. Masamba, C. Ruepert, L. E. Castillo, M. Shoeib, S. C. Lee, T. Harner and F. Wania  
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00499F, Paper

Graphical abstract: Neutral polyfluoroalkyl substances in the global Atmosphere
Assessment of environmentally persistent free radicals in soils and sediments from three Superfund sites
Albert Leo N. dela Cruz, Robert L. Cook, Barry Dellinger, Slawomir M. Lomnicki, Kirby C. Donnelly, Matthew A. Kelley and David Cosgriff  
Environ. Sci.: Processes Impacts, 2014,16, 44-52
DOI: 10.1039/C3EM00428G, Paper

Graphical abstract: Assessment of environmentally persistent free radicals in soils and sediments from three Superfund sites

Internal transcribed spacer rRNA gene sequencing analysis of fungal diversity in Kansas City indoor environments
William R. Rittenour, Christina E. Ciaccio, Charles S. Barnes, Michael L. Kashon, Angela R. Lemons, Donald H. Beezhold and Brett J. Green  
Environ. Sci.: Processes Impacts, 2014,16, 33-43
DOI: 10.1039/C3EM00441D, Paper

Graphical abstract: Internal transcribed spacer rRNA gene sequencing analysis of fungal diversity in Kansas City indoor environments

Field calibration of low density polyethylene passive samplers for gaseous POPs
Mohammed A. Khairy and Rainer Lohmann  
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00493G, Paper

Graphical abstract: Field calibration of low density polyethylene passive samplers for gaseous POPs

Bubble bursting as an aerosol generation mechanism during an oil spill in the deep-sea environment: laboratory experimental demonstration of the transport pathway
Franz S. Ehrenhauser, Paria Avij, Xin Shu, Victoria Dugas, Isaiah Woodson, Thilanga Liyana-Arachchi, Zenghui Zhang, Francisco R. Hung and Kalliat T. Valsaraj  
Environ. Sci.: Processes Impacts, 2014,16, 65-73
DOI: 10.1039/C3EM00390F, Paper

Graphical abstract: Bubble bursting as an aerosol generation mechanism during an oil spill in the deep-sea environment: laboratory experimental demonstration of the transport pathway

Bubble bursting as an aerosol generation mechanism during an oil spill in the deep-sea environment: molecular dynamics simulations of oil alkanes and dispersants in atmospheric air/salt water interfaces
Thilanga P. Liyana-Arachchi, Zenghui Zhang, Franz S. Ehrenhauser, Paria Avij, Kalliat T. Valsaraj and Francisco R. Hung  
Environ. Sci.: Processes Impacts, 2014,16, 53-64
DOI: 10.1039/C3EM00391D, Paper

Graphical abstract: Bubble bursting as an aerosol generation mechanism during an oil spill in the deep-sea environment: molecular dynamics simulations of oil alkanes and dispersants in atmospheric air/salt water interfaces

Evaluation of a novel personal nanoparticle sampler
Yue Zhou, Hammad Irshad, Chuen-Jinn Tsai, Shao-Ming Hung and Yung-Sung Cheng  
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00497J, Paper

Graphical abstract: Evaluation of a novel personal nanoparticle sampler

APEX (Aqueous Photochemistry of Environmentally occurring Xenobiotics): a free software tool to predict the kinetics of photochemical processes in surface waters
Marco Bodrato and Davide Vione  
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00541K, Paper

Graphical abstract: APEX (Aqueous Photochemistry of Environmentally occurring Xenobiotics): a free software tool to predict the kinetics of photochemical processes in surface waters

A review with recent advancements on bioremediation-based abolition of heavy metals
Nisha Gaur, Gagan Flora, Mahavir Yadav and Archana Tiwari  
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00491K, Critical Review

Graphical abstract: A review with recent advancements on bioremediation-based abolition of heavy metals

Leaching potential of metallic elements from contaminated soils under anoxia
Ramona Balint, Gheorghe Nechifor and Franco Ajmone-Marsan  
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00546A, Paper

Graphical abstract: Leaching potential of metallic elements from contaminated soils under anoxia

Testing flow-through air samplers for use in near-field vapour drift studies by measuring pyrimethanil in air after spraying
Trudyanne S. Geoghegan, Kimberly J. Hageman and Andrew J. Hewitt  
Environ. Sci.: Processes Impacts, 2014, Advance Article
DOI: 10.1039/C3EM00498H, Paper

Graphical abstract: Testing flow-through air samplers for use in near-field vapour drift studies by measuring pyrimethanil in air after spraying
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A novel spectroscopic technique for assessing vegetation stresses in post-mining sites

Novel spectroscopic techniques could provide a useful tool for monitoring the physiological status of vegetation in post-mining sites, according to a new study by Zuzana et al from the Charles University in Prague, which featured as our Cover Article in Issue 11.

Long-term lignite mining has caused widespread ecological damage in many areas across the world. The principal cause of these problems is acid mine drainage, which causes increased acidity of soil and water environments and subsequent  mobilization of heavy metals e.g. Cd, Zn, Co, Cu and Ni leading to plant uptake from contaminated soils.

Reforestation is a common method for reclamation of post-mining sites with Scots pine being a popular option due to its high ecological tolerance to diverse environments. Monitoring the effects of low pH conditions and heavy metal contamination and identifying key non-specific indicators of stress in this vegetation is therefore important in order to best develop the most effective remediation strategies for post-mining locations.

However, only a limited amount of work has so far been performed under field conditions to establish the effects of high acidity and heavy metal levels on the biochemical processes within vegetation and suitable biomarkers for these effects have not yet been identified. In this study, Zuzana et al. outline the results of a pilot study for monitoring reclaimed post-mining sites, developing a method to identify the key physiological stress factors in Scots pine trees.




Spectroscopic methods are becoming increasingly popular in environmental monitoring. They potentially offer a cheaper and faster alternative to conventional biochemical analysis. The approach in this study modelled the relationship between the visible to-near-infrared (VNIR) spectral properties of Scots pine needles and their key physiochemical properties, measured in the laboratory.

The most suitable biochemical traits identified as non-specific stress indicators for Scots pine trees were ; relative water content (fraction of weight decrease after drying),  content of photosynthetic pigments (chlorophyll a+b and carotenoids, and the ratio of these two components) and concentration soluble phenolic compounds.

The technique was applied to four sites in northwest Czech Republic, each exhibiting different levels of physiological stress. The method was able to successfully separate the different sites, using at least three of the above variables, based on their spectral reflectance data and validated using bootstrapped partial least squares regression (PLSR) modelling  predictions.

The study demonstrates the potential use for the VNIR spectroscopic technique for estimating the physiological status of vegetation in post-mining sites. The method has potential use in larger-scale monitoring studies, allowing simple and quick assessment of reclamation quality in post-mining regions using air-born or satellite hyperspectral data.


This paper is an ESPI HOT article and is of interest to researchers interested in contaminated land remediation, specifically post-mining sites, or anyone that likes trees.

Detection of multiple stresses in Scots pine growing at post-mining sites using visible to near-infrared spectroscopy, Lhotáková Zuzana et al, DOI: 10.1039/c3em00388d

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Semipermeable membrane devises (SPMDs) as models in dissolved hydrocarbon exposure studies

Crude oil spillages are a major ecological threat, exposing aquatic wildlife to high concentrations of toxic organic pollutants. This study by Van Scoy et al. demonstrates the potential usefulness of semi-permeable membrane devises (SPMDs) in monitoring the exposure of aquatic organisms to dissolved hydrocarbons from crude oil, and in assessing the toxic effects that these compounds may exert.

Oil spills and their environmental impacts are frequently in the public and media spotlight. In order to adequately address this issue it is essential to establish the most effective way to limit exposure to the toxic compounds released. It is common for chemical dispersants to be used following spillages. These accelerate the natural dispersion of oil by reducing the interfacial surface tension. While these are considered to be an effective treatment method, the ecological impact of dispersed oil needs to be considered.

In this study SPMDs were used to extract the bioavailable fraction of dissolved hydrocarbons present in both ‘undispersed’ and ‘chemically dispersed’ crude oil. SPMDs mimic the action of biological membranes by allowing passive diffusion of aqueous compounds through the lipid membrane. Here, this technique was used to monitor levels of key polycyclic aromatic hydrocarbons (PAHs), a class of pollutants shown to display toxic and bioaccumulative properties in aquatic organisms.

The use of SPMDs is favourable compared to living models in bioavailability studies, providing a relatively quick, economical and efficient method and also avoids biotransformation of compounds during the experiment. In this study, ultra high purity triolein (C57H104O6) was used to extract 7 PAHs, monitoring accumulation over a 24hr exposure time to simulate the initial period after a spillage. Concentrations of 7 PAHs were measured using gas chromatography with mass spectrometry (GC-MS).

It was shown that, while the initial crude oil loading was 8 times higher for the undispersed oil (2 g L-1) compared to the dispersed oil (0.25 g L-1), accumulation of PAHs was greater for the dispersed oil. This was attributed to the micelles, formed upon dispersant application, weathering over time. This would suggest the use of chemical dispersants as a remediation measure may increase the risk of exposure of aquatic organisms to toxic hydrocarbons.

The study demonstrates the usefulness of SPMDs in measuring concentrations of dissolved organic pollutants present in crude oil. Data from this technique, in combination with metabolomic data, could be a valuable tool in better understanding the bioavailability of dissolved hydrocarbons in crude oil and the possible toxic effects this can have on aquatic wildlife. The paper would therefore be of interest to ecotoxicologists investigating aquatic organisms in both saltwater and freshwater environments.

Use of semipermeable membrane devices (SPMDs) to characterize dissolved hydrocarbon fractions of both dispersed and undispersed oil by April R. Van Scoy, Jennifer Voorhees, Brian S. Anderson, Bryn M. Philips and Ronald S. Tjeerdema.  

DOI: 10.1039/C3EM00275F

This paper is part of the ESPI HOT articles series and is free to download* for the next 2 weeks  – grab it while it’s HOT!

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Free to access HOT articles!

These HOT articles were recommended by our referees and are free to access for 4 weeks*

Contaminated land: can acute exposure be a significant health risk? Two case studies and associated risk assessment methods George Kowalczyk, Mark Brown, Rebecca Twigg, William Welfare and Yolande Macklin  
DOI: 10.1039/C3EM00278K

The influence of glacial meltwater on alpine aquatic ecosystems: a review
Krista E. H. Slemmons, Jasmine E. Sarosa and Kevin Simon  
DOI: 10.1039/C3EM00243H

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Human exposure to aluminium
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DOI: 10.1039/C3EM00374D

 
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It’s an aluminium age: exploring human exposure

Aluminium is the most abundant metal in the Earth’s crust. Its range of desirable chemical and physical properties (e.g. low density, thermal conductivity, corrosion resistance etc) has made it the most widely used metal of the 21st century, utilised in a huge variety of products and applications, from kitchen utensils to aircraft parts, from food packaging to window frames. However, while the extracting and casting of this abundant resource yields many benefits, the disruption of natural geochemical and biochemical systems may expose organisms including humans to potential harm. It is of paramount importance that we fully understand the ways in which humans are exposed to aluminium and its behaviour within the body. This will allow the nature and extent of potential toxic effects to be assessed and enable people to live safely with these possible dangers.

In this article, which featured on the cover of Environmental Science: Processes & Impacts Issue 10, Christopher Exley provides a detailed and comprehensive critical review, addressing these issues. A broad range of specific aspects within the field of aluminium exposure are covered. The myriad ways in which humans are exposed to aluminium (including inhalation, diet and cosmetics) are discussed as well as the key impact routes (e.g. skin. nose, lung and gut), distribution networks within the body (e.g. blood) and excretion routes. The mechanisms through which aluminium can exert biochemical effects in humans (e.g. pro-oxidant activity, immunopotency and mutagenicity) are also described. Additionally, the article provides a complete and clear description of the aluminium ‘body burden’ (the balance between exposure and excretion).

This article challenges the current perception that aluminium is completely ‘safe’ and demonstrates the need to change our thinking regarding human exposure to metals like aluminium. Furthermore, several key knowledge gaps in this field are identified. Specific areas for future research, required to improve our understanding of aluminium exposure and toxicology, are outlined. In particular, the need to identify specific ‘targets’ within biological systems that may be more vulnerable to aluminium ‘attack’ than others is emphasised. Also, a need to establish an acceptable level of ‘safe’ exposure in humans is highlighted.

Exley suggests that gaining a full understanding of aluminium exposure and body burden in humans will require further data to be gathered from both laboratory and computer modelling approaches. This article will therefore be a valuable resource for researchers within these fields as well as for policy-makers at local and national levels.

Read the full article here:
Human exposure to aluminium, Christopher Exley, DOI : 10.1039/c3em00374d

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