Author Archive

Introducing Editorial Board Member Young-Shin Jun

In the second post of our Introducing series, we’re very pleased to introduce Editorial Board member Young-Shin Jun to the Environmental Science: Processes & Impacts blog readers!

Young-Shin Jun is an Associate Professor of Energy, Environmental & Chemical Engineering at Washington University (St. Louis, USA), where she leads the Environmental NanoChemistry Laboratory. She is a 2011 U. S. National Science Foundation CAREER award recipient. Her research focuses on interfacial reactions in complex aqueous systems. Her research group’s projects include elucidating physicochemical reaction mechanisms occurring during water reuse through aquifer storage, treatment, and recovery to secure underground sources for drinking water; improving our understanding of the fate and transport of contaminants and nanoparticles; and providing more environmentally sustainable CO2 sequestration strategies. Prior to her position at Washington University, she conducted postdoctoral research in Nanogeoscience at the University of California at Berkeley/Lawrence Berkeley National Laboratory, Berkeley, USA. She holds an S.M. and Ph.D. in Environmental Chemistry from Harvard University (Cambridge, USA). She received her B.S. and M.S. in Environmental Science and Engineering at Ewha Womans University (Seoul, Korea).

RESEARCH VISION: “In the face of unprecedented demands for energy and clean water, we simply must find ways to secure sustainable supplies of both.  At the same time, we must respect and restore the environment and reduce our emission of greenhouse gases. Maintaining a sustainable energy-water nexus is a grand environmental challenge, one which environmental scientists and engineers are uniquely positioned to undertake.  At complex environmental interfaces, various combinations of reactions can often occur simultaneously. A full understanding of dynamic interfaces at the molecular scale is essential in predicting the geochemical cycling of elements and the fate and transport of contaminants. This knowledge, in turn, will help us to develop better remediation methods for polluted sites, to design sustainable carbon sequestration and utilization, and to enhance our understanding of biomineralization and our development of environmentally benign bio-inspired materials. To advance our understanding of environmental interfacial reactions, my research group, the Environmental NanoChemistry Laboratory, in the Department of Energy, Environmental & Chemical Engineering at Washington University, has been providing in situ, real-time quantitative and qualitative information from unique experimental approaches. The dynamic environmental systems studied include nanoparticles’ formation and their transformation in natural and engineered aqueous systems, managed aquifer recharge, and energy-related subsurface operations. By providing crucial information for upscaling that is presently not available, we hope this research can benefit the larger scale engineering processes needed to make major impacts.”
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Critical Review: Measuring the flow of silver nanoparticles through the environment

silver nanoparticles in the environmentThis recently published article from Jing-Fu Liu et al. takes a critical view of the current investigations into the effects that silver nanoparticles have on the environment. It was published in January’s themed issue on Anthropogenic nanoparticles in the environment. 

Appropriate sampling, separation and analytical methods are vital, particularly for analysis of silver nanoparticles in complex environmental samples. This review covers: 

  1. A brief history of silver colloids in the environment
  2. Beneficial properties versus environmental concerns
  3. Analytical techniques, including combinations of different methods, and the different sample sources, such as aerosols and soil
  4. Factors and processes influencing fate and transport of AgNPs
  5. Environmental transformation
  6. Toxicity of silver nanoparticles and different silver species

Each of the above mentioned topics are interesting in themselves, but this article pulls the information together to give one wide perspective of the flow of silver nanoparticles through our environment and ways we can detect and analyse their effects. It highlights how much is still unknown and how complex such investigation will continue to be.

Silver nanoparticles in the environment
Su-juan Yu, Yong-guang Yin and Jing-fu Liu
DOI: 10.1039/C2EM30595J

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Introducing Editorial Board member Nora Savage

Beginning a small series of blog posts introducing the newest Editorial Board members of Environmental Science: Processes & Impacts, in this week’s post we are pleased to introduce Nora Savage and her research vision:

Nora Savage

Nora obtained her bachelors degree in Chemical Engineering in 1992 from Prairie View A&M University, in Prairie View, Texas.  She received two Masters Degrees (in Environmental Engineering and Environmental Science) from the University of Wisconsin-Madison, in Madison, Wisconsin in1995, and a doctoral degree in Environmental Science from the same institution in 2000. Her current position is that of environmental engineer at the U. S. Environmental Protection Agency (EPA) in Washington, DC in the Office of Research and Development (ORD).  Her focus areas include nanotechnology, pollution prevention, and sustainable life cycle approaches for emerging technologies. 

Nora is one of the Agency representatives on the Nanoscale Science, Engineering and Technology (NSET) subcommittee of the National Science and Technology Council that implements and coordinates activities and strategies of the National Nanotechnology Initiative (NNI) and has served in this role since 2001.  Recently she served as Co-Chair of the NNI’s Strategic Plan Task Force, the inter-agency work group that developed the 2011 NNI Strategic Plan. Nora has authored and co-authored numerous articles on nanotechnology in leading journals, including the Journal of Nanoparticle Research and Toxicological Sciences.  She was lead editor for the book “Nanotechnology for Water Applications” and has contributed chapters to several other books, including the Oxford Handbook of Nanoscience and Technology, vol. III.

Nora is currently the Chair of the 2013 Environmental Nanotechnology Gordon research Conference.

NORA’S RESEARCH VISION: “Currently the approaches for addressing human health and ecological protection involve assessing, controlling/mitigating exposure to individual contaminants based upon experimental or observed toxicity. Toxicity (hazard) and exposure data are accumulated and risks are assessed based upon single compounds or very simple mixtures. Many scientists and policy makers have called for better approaches for assessing and managing risks to existing and emerging compounds.
The development of “green” compounds is challenged by the creation of engineered nanomaterials with identical chemical formulas yet which exhibit different properties depending upon shape, size, and surface characteristics. As these novel compounds move through and between both environmental and biological media and undergo transformations, attendant properties are often altered as well. Consequently, it is not sufficient to amass toxicity data of the original or starting material if the goal is the protection of public and environmental health. The compound must be characterized throughout all life cycle stages. Subsequently toxicity testing upon the transformed compound or material would then provide more accurate information.
Multi-disciplinary research is required to achieve characterization of compounds through all life cycle stages. For example, engineers can explore processes and offer material mass balances, material scientist can provide detailed data on structure, morphology and other material properties, biologists and ecologists can provide information concerning movement through biological and ecological media, and social scientists can provide critical information on compound or product usages and behavioral patterns controlling exposure. Such research would also derive immense benefits from multi-cultural research teams. As challenges faced increase in complexity, solutions are achieved faster when analyzed by people of diverse backgrounds and experiences and with diverse approaches and perspectives,
By exploiting the novel properties of engineered nanomaterials with multi-disciplinary, international teams examining the resultant transformations as these compounds move through the ecosystem, improved data characterizing the environment will result. As scientific knowledge improves about how altered states of engineered nanomaterials result in altered properties, better understanding of complex mixtures will result. This will enable more accurate correlations of causal links among observed adverse biological and ecological effects, exposure, behavior, and compound concentrations. This knowledge will help usher in the development of true “green” compounds. The ultimate goal would be improved environmental assessments which can then pave the way towards more holistic public and environmental health protection.”
 

 

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Issue 4 online today! On-site porewater analysis, reviewing PBDE toxicity and xenobiotics in wastewater

The beautiful image on the outside front cover highlights important research from Beat Müller et al. This research conducted in Switzerland combines convenient technologies to develop a method for speedy, portable sediment porewater sampling and on-site analysis. This article was featured on the blog last week and you can browse the blog or read the post here. As a cover article, it’s also now free to access for 6 weeks*!

Sediment porewater extraction and analysis combining filter tube samplers and capillary electrophoresis
Natascha T. Torres, Peter C. Hauser, Gerhard Furrer, Helmut Brandl and Beat Müller
DOI: 10.1039/C3EM00068K

An interesting Frontier review from Xiao-Min Ren and Environmental Science: Processes & Impacts Editorial Board member Liang-Hong Guo on the likely impact of PBDE toxicity on the body, specifically looking at what is known about the molecular mechanism of PBDE in disruption of hormone receptor pathways and how PBDE toxicity is being investigated.

Molecular toxicology of polybrominated diphenyl ethers: nuclear hormone receptor mediated pathways
Xiao-Min Ren and Liang-Hong Guo
DOI: 10.1039/C3EM00023K

Issue 4 also contains HOT articles, two of which recently featured on the blog and both are still free to access* for the next couple of weeks:

Characterization of a portable method for the collection of exhaled breath condensate and subsequent analysis of metal content
Julie R. Fox, Ernst W. Spannhake, Kristin K. Macri, Christine M. Torrey, Jana N. Mihalic, Sorina E. Eftim, Peter S. J. Lees and Alison S. Geyh
DOI: 10.1039/C3EM30906A

Read the blog post here

A case-study on the accuracy of mass balances for xenobiotics in full-scale wastewater treatment plants
Marius Majewsky, Julien Farlin, Michael Bayerle and Tom Gallé
DOI: 10.1039/C3EM30884G

Read the blog post here

Curious to know more about Environmental Science: Processes & Impacts?

View the full issue here today

*Free access to individuals is provided through an RSC Publishing personal account. Registration is quick, free and simple

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Speedy, high-throughput sediment porewater extraction and analysis method

Collaborators at Eawag, the University of Basel, ETH Zurich and University of Zurich have come together to develop a faster, portable way to take sediment samples, extract porewater and analyse it in under 15 minutes.

Led by Beat Muller, the researchers combine a portable capillary electrophoresis instrument with MicroRhizon samplers in this Environmental Science :Processes & Impacts paper.

MicroRhizon samplers are made of chemically inert microporous tubing connected to a syringe and are inexpensive, portable and simple to use. The difficulty in analysis is that only a small sample volume is collected, extra handling and sample preparation is required and there is a risk of contamination in transferring the sample for analysis.

The previously developed portable capillary electrophoresis device with contactless conductivity detection eliminates these concerns as it enables sensitive detection of ionic compounds in the field immediately after sampling.

porewater sampling, MicroRhizonIn this article, the team applies this combination to porewater sampling and analysis, giving high spatial resolution.

The method is validated by sampling of sediment from a eutrophic lake, comparing the results to those from ion chromatography. They successfully separate out major inorganic ionic compounds in under 15 minutes. The disturbance of the sediment samples is minimal and zero-oxygen conditions were maintained without difficulty. No splitting, acidification or dilution of the sample is necessary.

Such speedy porewater analysis will be beneficial for the study of oxidizing agents and nutrients in organic matter. Read the full article here as it’s now free to access for the next 4 weeks*

Sediment porewater extraction and analysis combining filter tube samplers and capillary electrophoresis
Natascha T. Torres, Peter C. Hauser, Gerhard Furrer, Helmut Brandl and Beat Müller
DOI: 10.1039/C3EM00068K

*Free access to individuals is provided through an RSC Publishing personal account. Registration is quick, free and simple

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HOT article: The inaccuracy of wastewater microcontaminant removal efficiency measurements

Reported removal efficiencies of micropollutants at wastewater treatment plants vary a great deal for the same substance, with negative removal efficiencies even being reported and simply averaged out.

Often, to reduce cost and effort, sampling studies are very short at one to two days. The efficiency is then based on a calculation of mass balancing the sample loads in influent and effluent, using the flawed assumptions that the volume of each is equal and that micropollutant concentrations are in steady-state conditions at all times.

Researchers at the Resource Center for Environmental Technologies in Luxembourg saw this need to systematically examine this method and the accuracy of it with regard to the sampling method and conditions. This HOT article describes the application of hydraulic modeling to match up the influent and effluent loads, reducing uncertainties.

Hydraulic residence times are often used in chemical engineering but not in evaluation of wastewater treatment sampling. In previous modeling work, the team has concluded that the load carried by an effluent sample taken over the course of one day is made up of influent load from the days before. This study takes this and attempts to calculate how much of one day’s micropollutant influent load ends up in a day’s effluent sample. The number of influent sampling days was gradually increased until 80% of the effluent sample was accounted for.

They provide a model that can be adapted for use in other wastewater treatment plants and recommend best practice for taking inevitable errors ranges into account. This article is free to access for the next 4 weeks* so you can read it now at:

A case-study on the accuracy of mass balances for xenobiotics in full-scale wastewater treatment plants
Marius Majewsky, Julien Farlin, Michael Bayerle and Tom Gallé
DOI: 10.1039/C3EM30884G

*Free access to individuals is provided through an RSC Publishing personal account. Registration is quick, free and simple

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Webinar: The power of modern HPTLC

Join Chemistry World and Advion for a webcast on the latest developments in HPTLC technology.

WHAT: Professor Morlock from the University of Giessen, Germany, will give an overview of current HPTLC methodology, explore some examples of HPTLC-MS coupling and review other current hyphenations in HPTLC. By the end of this free webinar, you will be able to:
– Recognise the power of modern HPTLC
– Learn about current hyphenations in HPTLC
– Understand the principle of elution-based HPTLC-MS
– Recognise how HPTLC hyphenations efficiently support analyses

WHEN: Wednesday, 20 March 2013 – 15:00 GMT

HOW: Click here to register (free)

Register today, even if you can’t make it on 20th March, and we’ll send you a link to the recorded webinar.

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HOT article: Standardising analysis of biomarkers in exhaled breath condensate

Julie Fox et al. tackle the problem of how different studies of exhaled breath condensate (EBC) sampling can be directly compared in this HOT article dedicated to the late Dr Alison Geyh. This requires standardisation of the method and equipment used, which are both highly dependent on the nature of the biomarker being assessed and the population studied.

The group concentrate on the assessment of metals, as elemental biomarkers that are not affected by degradation through the analysis process. The researchers based at University of Washington, Johns Hopkins Bloomeberg School of Public Health and ICF International, USA, incorporated a number of quality control aspects meaning the method can be used for different EBC sample types.

The instrument used was the commercially available Rtube, with a polypropylene condensing surface and an aluminium sleeve that is chilled to condense the EBC. This is a cheaper, more portable option with no temperature control during sampling. They add a spirometer for recording ventilation and subjects were trained to use a visual incentive spirometer to keep their breathing consistent during sampling. A HEPA filter reduces exposure to airborne particles and the modified Rtube is also able to connect up to a temperature-controlled device, the EcoVent, as needed.

The found that is vital to evaluate any possible sources of contamination prior to the experiment. The group measured a number of collection parameters and recommend detailed description of these for all experiments.

The method was validated by measurements of Mn, Cd, Ni and Cr in an unexposed population on a small scale, with a focus on Mn. Wider conclusions about the general population cannot be made from this small study, however this HOT article presents a methodology and protocol recommendations for future EBC studies that is portable, economical and widely applicable.

This article is now free to access for the next 4 weeks*, so you can read the detail of the parameters measured and the example study now:

Characterization of a portable method for the collection of exhaled breath condensate and subsequent analysis of metal content
Julie R. Fox, Ernst W. Spannhake, Kristin K. Macri, Christine M. Torrey, Jana N. Mihalic, Sorina E. Eftim, Peter S. J. Lees and Alison S. Geyh
DOI: 10.1039/C3EM30906A

*Free access to individuals is provided through an RSC Publishing personal account. Registration is quick, free and simple

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HOT cover article: Long-term study of active capping effects on contaminant migration and bioaccumulation

A team at The University of Texas at Austin, USA, present the results of a long-term study of polycyclic aromatic hydrocarbon monitoring at a site of contaminated sediment capping by the Anacostia River in Washington DC in this HOT paper, which was featured on the cover of Issue 3.

Capping sediments with clean material to create a barrier between benthic organisms and contamination is a technique to reduce contamination of sediments in situ. PAHs still present an environmental risk long after the source has been eliminated and capping with sand can act as a diffusive barrier giving a clean environment for benthic organisms. Often now materials that actively absorb the contaminants are used, but they usually need a sand layer for benthos organisms to survive.

The capping took place in 2004 with four different materials – AquaBlokTM (clay-like material with permeability control), coke in a Reactive Core MatTM (to assess low density material in a thin mat), apatite (for heavy metal sequestration) and sand for comparison. The indicator used to assess chemical migration through these materials was monitoring of pore water concentration profiles. Solid-phase concentration could not be used to compare them due to the limited sorption capacity of sand.

They concluded that there were significant concentrations throughout the caps and that the rates of migration in the caps were as expected for the transport characteristics at the site and sorption effect of the materials slowing migration. The caps reached steady state after a few years due to surface re-contamination, however the actual contaminant concentrations were lower than uncapped areas. Tidal dispersion was the primary mixing mechanism in the caps. The team also evaluated bioaccumulation and the ability of pore-water profiling to predict the observed values. Predictions based on pore water concentrations were more accurate than those based on a solid-phase approach.

Read the full discussion of the differences between the capping materials and the results of sampling over time now, as this cover article is still free to access for 5 more weeks*

Long-term PAH monitoring results from the Anacostia River active capping demonstration using polydimethylsiloxane (PDMS) fibers
David J. Lampert, Xiaoxia Lu and Danny D. Reible
DOI: 10.1039/C3EM30826J

*Free access to individuals is provided through an RSC Publishing personal account. Registration is quick, free and simple

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Overcoming environmental data loss, occupational health, active capping materials and more in Environmental Science: Processes & Impacts Issue 3, online now!

This issue’s outside front cover features a HOT article by Richard Brown at the National Physical Laboratory focused on a simple modelling method to overcome data loss, particularly when the data varies seasonally, to provide more representative annual averages. All of our cover articles are made free to access for 6 weeks*, so read it by clicking the link:

Data loss from time series of pollutants in ambient air exhibiting seasonality: consequences and strategies for data prediction
Richard J. C. Brown
DOI: 10.1039/C3EM30918E

This was also featured in this week’s blog posts, find the post here!


Work from Danny Reible et al. at the University of Texas at Austin, USA is highlighted on the inside front cover. This HOT cover article presents an analysis of a long term study monitoring polycyclic aromatic hydrocarbons migration through capping materials at the Anacostia Rive, Washington DC, USA. They use an innovative passive sampling method with PDMS and assess bioavailability of PAHs using pore water profiles.

Long-term PAH monitoring results from the Anacostia River active capping demonstration using polydimethylsiloxane (PDMS) fibers
David J. Lampert, Xiaoxia Lu and Danny D. Reible
DOI: 10.1039/C3EM30826J


Issue 3 also contains high quality environmental research such as that from researchers at The University of Minnesota studying the eight volatile organic compounds that swine production workers are most exposed to. This work was also the subject of a recent blog post, so you can read the blog post here for the highlights of the work or read the full detailed study by clicking the article link below. This article is still free to access for the next 2 weeks!*

Health risk assessment of occupational exposure to hazardous volatile organic compounds in swine gestation, farrowing and nursery barns
Neslihan Akdeniz, Larry D. Jacobson and Brian P. Hetchler
DOI: 10.1039/C2EM30722G

To learn more about the latest Environmental Science: Processes & Impacts research, view the full issue here!

*Free access to individuals is provided through an RSC Publishing personal account. Registration is quick, free and simple

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