25th Japan Society for Environmental Chemistry

The 25th Japan Society for Environmental Chemistry Annual Meeting was held in Niigata, Japan on 8-10 June 2016.

During the award ceremony Hiromitsu Urakami from the Royal Society of Chemistry presented several certificates to poster prize winners on behalf of our environmental science journals.

Congratulations to all of the winners!

Environmental Science: Processes & Impacts Winners:

Tomohiko Nakano, Kyoto University

Poster title: Development of a molecularly imprinted polymer for selective adsorption of estrogenic substances

Hiromitsu Urakami (left), Tomohiko Nakano (right)

Congratulations to Ayaka Onishi, University of Tokyo who also won an Environmental Science: Processes & Impacts poster prize for the poster entitled;

“A study on anomaly concentration of arsenic to ferruginous precipitate in Tokyo, Japan”

And the winners for the Environmental Science: Nano and Environmental Science: Water Research and Technology poster prizes were Kosuke Ranaka and Suzumi Nishimura. More details can be found on our  ES: Nano and ES:Water blogs.

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Amines in Shanghai – a new quantitative analysis

Amines are (usually smelly) organic compounds that contain a basic nitrogen atom bearing a lone electron pair. They are often used in solvents and reagents, which causes them to be released to the atmosphere. Atmospheric amines may be dangerous for several reasons;

  • Oxidation of amines can result in some highly carcinogenic compounds
  • The release of amines to the air can alter the nitrogen cycle
  • Amines can contribute to chemical processes, including nucleation and the formation of aerosols, which can affect the water cycle by generating rain in unexpected locations

Structure of ethylamine (image by @moleculd, http://twitter.com/moleculd)

Thus, it is important that we can rely on effective ways of measuring the concentration of amines in the atmosphere. In this paper developed by chemists and engineers at Fudan University in Shanghai, China, the authors optimize a new quantitative analysis of aliphatic amines found in urban samples. To do so, these researchers have created a novel on-line derivatization of amines that transforms them into highly fluorescent molecules that can be separated and analyzed by HPLC.

This new method simplifies the experimental efforts normally required by offline derivatizations. The authors also demonstrated, using different concentrations of certified standards, that the method is statistically accurate. In addition, the procedure is very sensitive, reaching detection limits of 1 microgram per liter (ppb) for all the aliphatic amines that were analyzed.

Pollution over Shanghai (picture by Peter Dowley, https://www.flickr.com/people/40271931@N00)

Finally, it is worth highlighting that, using their own novel method, the authors have been the first to detect and quantify the seasonal variation of aliphatic amines in the pollution-fog over Shanghai. They have proved that these organic molecules are more abundant during the summer. Could this have any implications on local weather?

Interested in this research? Click on the link below to read the full article for free*

Quantitative analysis of aliphatic amines in urban aerosols based on online derivatization and high performance liquid chromatography.
X. Huang, C. Deng, G. Zhuang, J. Lin, and M. Xiao.
Environ. Sci.: Processes Impacts, 2016, Advance Article
DOI: 10.1039/C6EM00197A

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About the webwriter

Fernando Gomollón-Bel is a PhD Student at the ISQCH (CSIC-University of Zaragoza). His research focuses on asymmetric organic synthesis using sugars as chiral-pool starting materials towards the production of fungical transglycosidase inhibitors.

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*Access is free until 12/07/2016 through a registered publishing personal account.

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Unconventional hydrocarbons – Understanding the Potential Environmental Impacts

A post by Mindy Dulai, Senior Programme Manager, Science at the Royal Society of Chemistry

In the continuing drive to meet the world’s future energy needs, few can have missed the increased recent prominence of unconventional hydrocarbons. The extraction of resources such as shale gas, using techniques like hydraulic fracturing (or fracking) has gained attention from around the world, both for its potential to fulfil our energy requirements, as well as due to concerns around possible environmental impacts.

Chemistry has a strong role to play in helping us to understand potential environmental impacts, particularly areas such as air and water quality. The Royal Society of Chemistry supports the research community examining these issues, as chemical sciences research can help to inform broader policy decisions on this issue. We publish papers and books across our portfolio of journals, including those that encourage scientific debate and have actively supported those in the research community to share knowledge and advance science. To mark the publication of a report that explores research questions in this area, we have gathered some of our best publications on this topic to share with readers.

Unconventional hydrocarbon extraction in different countries has evolved at different rates. In the US there has been rapid exploration that has led to commercial scale production, whilst in the UK we are at a much earlier stage of the debate. Examining the situation in places like the US, which has a comparatively more established shale gas industry, can help us to determine what is known about the potential environmental impacts and where research, including chemistry, can help to address unknowns.

In November 2015, the UK Natural Environment Research Council (NERC), the US National Science Foundation (NSF) and the Environment, Sustainability and Energy Division of the Royal Society of Chemistry brought together researchers from the US and the UK at a workshop on Improving the Understanding of the Potential Environmental Impacts Associated with Unconventional Hydrocarbons. The aim of the workshop was to share knowledge in this rapidly changing area, particularly with respect to identifying research gaps and areas where future research may be needed. The range of topics covered by the workshop was broad, including areas such as air quality and wastewater treatment, which have a direct link with the chemical sciences, through to seismicity and socioeconomic impacts.

Participants at the workshop had the opportunity to present current research in their field, taking into account the specific situation in their country.  Discussions at the workshop examined similarities and differences between the different nations, leading onto the identification of knowledge gaps and future research needs.

The workshop’s co-chairs, Professor Richard Davies of Newcastle University and Professor Danny Reible at Texas Tech used the discussions from the meeting to produce a report, Joint US-UK Workshop on Improving the Understanding of the Potential Environmental Impacts Associated with Unconventional Hydrocarbons. The report captures key research gaps and needs in a whole range of areas from community engagement, to human health to waste water management.

Professor Richard Davies commented: “This workshop represented a valuable opportunity to prioritise and tailor research questions that could help us to better understand any potential environmental impacts if unconventional hydrocarbon extraction were to take place in the UK. The report examines both near-term and long-term research priorities for the research communities working in this area”.

The report will be relevant to researchers working on unconventional hydrocarbon extraction, outlining future research opportunities and needs. You can watch Professor Fred Worrall, one of the UK workshop participants talk about some of the points covered at the workshop in his lecture Exploring the impact of the unknown: a potential UK shale gas industry. Fred’s work on monitoring emissions relating to onshore oil and gas operations is also the subject of a recent Education in Chemistry article.

We hope that you will enjoy reading about both recent research advances and future areas for investigation in an area that will likely continue to feature in both scientific and public discourse.

Books

Fracking
Editors: R E Hester, R M Harrison
Print publication date: 02 Sep 2014
DOI: 10.1039/9781782620556

Principles and Practice of Analytical Techniques in Geosciences
Editor: Kliti Grice
Print publication date: 11 Sep 2014
DOI: 10.1039/9781782625025

Reviews

Evolving shale gas management: water resource risks, impacts, and lessons learned
Brian G. Rahm and Susan J. Riha
Environ. Sci.: Processes Impacts, 2014,16, 1400-1412
DOI: 10.1039/C4EM00018H

Use of stable isotopes to identify sources of methane in Appalachian Basin shallow groundwaters: a review
J. Alexandra Hakala
Environ. Sci.: Processes Impacts
, 2014,16, 2080-2086
DOI:
10.1039/C4EM00140K

Unconventional oil and gas extraction and animal health
M. Bamberger and   R. E. Oswald
Environ. Sci.: Processes Impacts
, 2014,16, 1860-1865
DOI:
10.1039/C4EM00150H

Practical measures for reducing the risk of environmental contamination in shale energy production
Paul Ziemkiewicz, John D. Quaranta and Michael McCawley
Environ. Sci.: Processes Impacts
, 2014,16, 1692-1699
DOI: 10.1039/C3EM00510K

Air quality concerns of unconventional oil and natural gas production
R. A. Field, J. Soltis and   S. Murphy
Environ. Sci.: Processes Impacts
, 2014,16, 954-969
DOI:
10.1039/C4EM00081A

Analysis

Deciphering the true life cycle environmental impacts and costs of the mega-scale shale gas-to-olefins projects in the United States
Chang He and   Fengqi You
Energy Environ. Sci.
, 2016,9, 820-840 DOI: 10.1039/C5EE02365C

Wells to wheels: water consumption for transportation fuels in the United States
David J. Lampert, Hao Cai and Amgad Elgowainy
Energy Environ. Sci.
, 2016,9, 787-802
DOI:
10.1039/C5EE03254G

Papers

Solid-phase extraction followed by gas chromatography-mass spectrometry for the quantitative analysis of semi-volatile hydrocarbons in hydraulic fracturing wastewaters
Julia Regnery, Bryan D. Coday, Stephanie M. Riley and  Tzahi Y. Cath
Anal. Methods
, 2016,8, 2058-2068
DOI:
10.1039/C6AY00169F

Partitioning of naturally-occurring radionuclides (NORM) in Marcellus Shale produced fluids influenced by chemical matrix
Andrew W. Nelson, Adam J. Johns, Eric S. Eitrheim, Andrew W. Knight, Madeline Basile, E. Arthur Bettis III, Michael. K. Schultz and   Tori Z. Forbes
Environ. Sci.: Processes Impacts
, 2016,18, 456-463
DOI:
10.1039/C5EM00540J

A liter-scale microbial capacitive deionization system for the treatment of shale gas wastewater
Casey Forrestal, Alexander Haeger, Louis Dankovich IV, Tzahi Y. Cath and   Zhiyong Jason Ren
Environ. Sci.: Water Res. Technol.
, 2016,2, 353-361
DOI:
10.1039/C5EW00211G

Detection of water contamination from hydraulic fracturing wastewater: a μPAD for bromide analysis in natural waters
Leslie J. Loh,a Gayan C. Bandara,a Genevieve L. Webera and  Vincent T. Remcho*a

Analyst, 2015,140, 5501-5507
DOI:
10.1039/C5AN00807G

Microbial capacitive desalination for integrated organic matter and salt removal and energy production from unconventional natural gas produced water
Casey Forrestal, Zachary Stoll, Pei Xu and  Zhiyong Jason Ren
Environ. Sci.: Water Res. Technol.
, 2015,1, 47-55
DOI: 10.1039/C4EW00050A

Stimuli-responsive/rheoreversible hydraulic fracturing fluids as a greener alternative to support geothermal and fossil energy production
H. B. Jung, K. C. Carroll, S. Kabilan, D. J. Heldebrant, D. Hoyt, L. Zhong, T. Varga, S. Stephens, L. Adams, A. Bonneville, A. Kuprat and   C. A. Fernandez
Green Chem.
, 2015,17, 2799-2812
DOI:
10.1039/C4GC01917B

Geo-material microfluidics at reservoir conditions for subsurface energy resource applications
Mark L. Porter, Joaquín Jiménez-Martínez, Ricardo Martinez, Quinn McCulloch, J. William Carey and Hari S. Viswanathan
Lab Chip
, 2015,15, 4044-4053
DOI:
10.1039/C5LC00704F

Shale gas-to-syngas chemical looping process for stable shale gas conversion to high purity syngas with a H2:CO ratio of 2:1
Siwei Luo, Liang Zeng, Dikai Xu, Mandar Kathe, Elena Chung, Niranjani Deshpande, Lang Qin, Ankita Majumder, Tien-Lin Hsieh, Andrew Tong, Zhenchao Sun and Liang-Shih Fan
Energy Environ. Sci.
, 2014,7, 4104-4117
DOI:
10.1039/C4EE02892A

Organic compounds in produced waters from shale gas wells
Samuel J. Maguire-Boyle and Andrew R. Barron
Environ. Sci.: Processes Impacts
, 2014,16, 2237-2248
DOI:
10.1039/C4EM00376D

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

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Between a rock and a hard place: greenhouse gas storage and natural resource extraction

a blog article by Abha Parajulee, PhD student at the University of Toronto

Humans are continuing to release increasing amounts of greenhouse gases to the atmosphere that have been implicated as key contributors to climate change. One major greenhouse gas is CO2. It is estimated that geological storage could result in a 17% reduction in atmospheric CO2 by 2050. Such projects aim to use sedimentary basins as they are believed to be the safest option for long-term storage of CO2 and other greenhouse gases. However, sedimentary basins are also valued for a range of extractable natural resources such as groundwater, oil and gas, and geothermal energy. Thus, there is a need to understand the potential interactions between these resources and subsurface storage of CO2 when targeting a particular site for CO2 storage.

A recently published study involving researchers from various institutes in Western Australia explain the potential risks involved with geological CO2 storage. Considering all the potential interactions between basin resource use and CO2 storage, the authors outline a Framework for Basin Resource Management Strategy (FBRMS) for optimizing interactions that may occur during the management of sedimentary basins.

Potential impacts of CO2 geological storage on other basin resources (reproduced from K. Michael
et al., EAGE Third Sustainable Earth Sciences 2015 Conference, DOI: 10.3997/2214-4609.201414262)

The initial stage of the FBRMS is an assessment of potential basins for CO2 storage based on containment potential of the subsurface. Optimal conditions include thick layers of low permeability rocks such as shales and anhydrites that can effectively cap the CO2. Lateral containment should be provided by lateral decreases in permeability, low permeability faults, or, in the absence of physical barriers, residual trapping, dissolution into water and mineral formation via reactions with the subsurface matrix. In addition to geologic characterization, modelling, monitoring and risk assessment are crucial for verifying long-term CO2 containment.

Also considered in the FBRMS are the two general means by which CO2 storage can affect other basin resources: migration and increasing basin pressure. Vertical or horizontal migration may result in contamination of natural gas or another currently used or potentially extractable resource.

Once CO2 is present in the subsurface, the future potential use of the injected area is instantly limited. An important concern associated with using shale basins is that shale may be used as an unconventional gas resource in future, and the methods for utilizing this resource negate its effectiveness as a long-term cap for CO2 storage. Though the probability is extremely low, increasing subsurface pressure from CO2 injection could also force saline water upwards along a wellbore or through existing fractures into groundwater resources, or may even cause fractures. Regardless of the likelihood, identifying all of these risks is an important facet of the FBRMS, presumably leading to relevant monitoring activities. On the other hand, increased pressure could also be beneficial in counteracting reduced pressure in mature oil or gas fields, low groundwater levels, or subsidence.

The FBRMS integrates all of these concerns to evaluate the likelihood of various basin resource-storage interactions, how beneficial or detrimental the interactions would be, and to determine how best to manage these interactions. It is intended to be used by various project stakeholders throughout the lifetime of a project, and may require intensive data collection or expert risk assessment depending on the individual project being assessed.


To read the full paper for free*, click the link below:

Framework for the assessment of interaction between CO2 geological storage and other sedimentary basin resources
K. Michael, S. Whittaker, S. Varma, E. Bekele, L. Langhi, J. Hodgkinson, and B. Harris
Environ. Sci.: Processes Impacts,
2016, 18, 164-175
DOI: 10.1039/C5EM00539F

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About the webwriter

Abha Parajulee is a Ph.D. student at the University of Toronto Scarborough. She is interested in water resources and the behavior of organic contaminants in urban environments.

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* Access is free until 01/06/2016 through a registered RSC account.

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Are we eating flame retardants?

a blog article by Fernando Gomollón-Bel, PhD student at the University of Zaragoza

Most of the materials we use nowadays are impregnated with several chemicals to make them fireproof and meet fire safety regulations. These are classically halogenated compounds such as polybrominated diphenyl ethers (PBDEs). Recently, the food safety authorities in the EU banned PBDEs because several studies linked them to hepatic damage and perturbations in metabolism.

Environ. Sci.: Processes Impacts

Hence, chemists developed a new kind of fire retardants known as hexabromocyclododecanes (HBCDs). Manufacturers of goods such as plastics, textiles and electronic equipment, are increasingly using these compounds. However, HBCDs may not be an ideal solution: recent studies found them in dust, air, sediments, and sewage in areas surrounding electronic waste (or e-waste) processing plants. And what is worse, the presence of HBCDs has also been reported in eggs, while researchers have confirmed human exposure from eating food sourced near the e-waste treatment plants. These are concerning issues, since these chemical are potentially toxic, persistent and bioaccumulative.

In this article published in Environmental Science: Processes & Impacts, Dr. Fang Tao and co-workers investigated the presence of HBCDs and other fire retardants in fish, pigs and free-range chickens reared in areas that could have been polluted by e-waste plants in Bui Dau, Vietnam. In addition to this, the team also took samples from supposedly non-contaminated zones both in Vietnam and Japan and analysed them.

The authors reported that HBCDs, as well as other emerging fire retardants, are found in chicken, fish and pork samples collected near the e-waste processing plant in Bui Dau. According to these data, locals may be ingesting dangerous amounts of toxic, accumulative chemicals. Although the dangers of some of these compounds are not completely defined yet, the researchers suggest to keep studying this phenomenon: the quantity of these contaminants in the environment may rise soon.

Interested in this research? Click on the link below to read the full article for free*

Emerging halogenated flame retardants and hexabromocyclododecanes in food samples from an e-waste processing area in Vietnam
Fang Tao, Hidenori Matsukami, Go Suzuki, Nguyen Minh Tue, Pham Hung Viet, Hidetaka Takigami and Stuart Harrad.
Environmental Science: Processes and Impacts, 2016, Advance Article
DOI: 10.1039/C5EM00593K

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About the webwriter

Fernando Gomollón-Bel is a PhD Student at the ISQCH (CSIC-University of Zaragoza). His research focuses on asymmetric organic synthesis using sugars as chiral-pool starting materials towards the production of fungical transglycosidase inhibitors.

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* Access is free until 11/04/2016 through a registered RSC account.

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Introducing our new Associate Editors

Helen, Matt and Paul join the Environmental Science: Processes & Impacts team as Associate Editors

We are delighted to introduce Helen Hsu-Kim, Matthew MacLeod and Paul Tratnyek as three new Associate Editors for Environmental Science: Processes & Impacts.

Helen, Matt and Paul join Liang-Hong Guo and Ed Kolodziej as Associate Editors handling submissions to the journal – more details about their research interests are given below.


Helen Hsu-Kim
Duke University, USA

Heileen (Helen) Hsu-Kim is the Yoh Family Associate Professor of Environmental Engineering at Duke University. Her expertise areas include aquatic geochemistry, biogeochemistry of metal pollutants in the environment, and nanogeoscience.

Ongoing research activities in Dr. Hsu-Kim’s group include studies on mercury biogeochemistry and remediation, mineral-microbe interactions, the disposal implications and reuse opportunities for coal ash, and the environmental impacts of nanotechnology. Additional details of the Hsu-Kim research group can be found online here.

Please note that Professor Hsu-Kim will start handling submissions starting on June 2016.


Matthew MacLeod
Stockholm University, Sweden

Matthew MacLeod is Professor of Environmental Chemistry at the Department of Environmental Science and Analytical Chemistry at Stockholm University. He holds a Bachelor of Science degree in Chemistry from the University of Victoria (British Columbia, Canada), and a PhD in Environmental Chemistry from Trent University (Ontario, Canada).

He was a post-doctoral fellow at the Lawrence Berkeley National Laboratory in Berkeley, California, USA, and a Research Group Leader at the Swiss Federal Institute of Technology (ETH) in Zürich, Switzerland.

Since 2010 he has been a faculty member at Stockholm University, Sweden.  Prof. MacLeod’s research interests include the fate, exposure and effects of persistent organic pollutants (POPs), modeling chemical pollutants, and environmental impacts of micro- and macro-plastics.


Paul Tratnyek
Oregon Health & Science University, USA

Paul G. Tratnyek is currently Professor, and Associate Head, in the Division of Environmental and Biomolecular Systems (EBS) and Institute of Environmental Health (IEH), at the Oregon Health & Science University (OHSU).

He received his Ph.D. in Applied Chemistry from the Colorado School of Mines (CSM) in 1987; served as a National Research Council Postdoctoral Fellow at the U.S. Environmental Protection Agency Laboratory in Athens, GA (ERD-Athens), during 1988; and as a Research Associate at the Swiss Federal Institute for Water Resources and Water Pollution Control (EAWAG) from 1989 to 1991.

His research concerns the physico-chemical processes that control the fate and effects of environmental substances, including minerals, metals (for remediation), organics (as contaminants), and nanoparticles (for remediation, as contaminants, and in biomedical applications).

Dr. Tratnyek is best known for his work on the degradation of groundwater contaminants with zero-valent metals, but his interests extend to all aspects of contaminant reduction and oxidation (redox) in all aquatic media. Some of his recent work emphasizes the fate/remediation of emerging contaminants (e.g., nanoparticles and 1,2,3-trichloropropane).

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The appointments of Helen, Matt, and Paul, illustrate the exciting future for Environmental Science: Processes & Impacts, as outlined by Editor-in-Chief Professor Kris McNeill in his recent Editorial. We are delighted to welcome them to the Environmental Science: Processes & Impacts team.

Interested in the latest news, research and events of the Environmental Science journals? Find us on Twitter: @EnvSciRSC

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The dangers of mercury in solid waste landfills

a blog article by Fernando Gomollón-Bel, PhD student at the University of Zaragoza

The (Mad) Hatter from Carroll's Alice in Wonderland (Illustration by John Tenniel - Public Domain)

The Hatter in Alice in Wonderland may not have been mad after all. He might have suffered from mercury poisoning! Thankfully, nowadays we know mercury is a dangerous element in almost all its forms. Organomercury compounds such as monomethylmercury (MMHg) and dimethylmercury (DMHg) are especially hazardous: not only because of their extreme toxicity but also because they can be bio-magnified in the food web. Moreover, mercury can travel the biosphere through air, water and soil, increasing the danger.

Even if we have stopped using mercury thermometers, a big number of household and industrial products still use this liquid metal. A lot of these products end up in landfills where they are treated as conventional waste, and may liberate dangerous amounts of this toxic metal to the atmosphere and soil.

In this critical review published in Environmental Science: Processes & Impacts, scientists analyze solid waste management in landfills and the chemistry of mercury, as well as the release of this metal into the environment and the possible bio and geological transformations it may suffer. As a conclusion, researchers review a series of studies that should be considered in depth in order to understand the problem of mercury release and to, eventually, find a solution.

As described in this work, landfills –mainly when they undergo the so-called anaerobic phase– present the ideal conditions (pH, redox, organic matter) for mercury to be speciated and transformed, then dissolved, mobilized and disseminated within the biosphere. It is mostly released as Hg(0) in gas form, but other species like MMHg and DMHg may also be produced and incorporated to soil and water reservoirs.

Whether you are a specialist in mercury or not, this review will surely captivate you. Landfills may seem boring, but the chemistry underneath is fascinating, like the liquid metal that fascinated alchemists for centuries. Remember, mercury was the prima materia from which all metals were formed!


Interested in this research? Click on the link below to read the full article for free*:

Biogeochemical transformations of mercury in solid waste landfills and pathways for release
Sung-Woo Lee, Gregory V. Lowry and Heileen Hsu-Kim.
Environmental Science: Processes & Impacts 2016, 18, 176-189
DOI: 10.139/C5EM00561B

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About the webwriter

Fernando Gomollón-Bel is a PhD Student at the ISQCH (CSIC-University of Zaragoza). His research focuses on asymmetric organic synthesis using sugars as chiral-pool starting materials towards the production of fungical transglycosidase inhibitors.

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* Access is free until 18/03/2016 through a registered RSC account.

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Sun, wind, and a crowd: Tough days in the life of a passive sampler?

a blog article by Abha Parajulee, PhD student at the University of Toronto

Passive air samplers (PAS) have found great utility in monitoring environmental concentrations of semivolatile organic contaminants (SVOCs) all over the world. They provide a picture of longer-term average air concentrations of SVOCs while being relatively portable, low-cost and extremely low-maintenance. Knowing the deployment time, the amount of chemical accumulated in the passive sampling medium (PSM), and the sampling rate derived when a PAS is first calibrated before widespread use, a time-averaged volumetric air concentration can be calculated.

Graphical Abstract

A key assumption underlying the calculation of PAS-derived air concentrations is that the passive sampling medium takes up chemicals uniformly. But this assumption has not been thoroughly tested so far and studies to date have indicated that the sampling rates of some commonly used PSM can differ with position inside a sampler housing. For example, sampling rates decreased with increasing distance from the opening at the bottom of a cylindrical sampler housing for the commonly used styrene-divinylbenzene copolymer or “XAD” resin.

In a study recently published in Environmental Science: Processes & Impacts, Zhang and co-workers at the University of Toronto Scarborough have put their XAD PAS to the test once more to determine if exposure to sunlight, wind, and the presence of multiple units of XAD-filled mesh cylinders in one PAS housing caused differential chemical uptake across the length of a single cylinder.

The chemicals of interest in this series of experiments, polychlorinated biphenyls (PCBs), were chosen because their environmental partitioning properties are inclusive of a range of SVOCs commonly measured in the environment. One indoor experiment included axially segmented PAS at four indoor locations, one of which also used fans to simulate the effect of wind. At one of the indoor locations, a similar experiment was conducted outdoors, where the effect of heat conduction resulting from sunshine was also tested. This involved using PAS with regular housings, housings painted black to enhance heat absorption, and housings shaded by a steel cover.

Two additional experiments varied the number of mesh cylinders inside each housing. One experiment deployed a pair of PAS containing one and four mesh cylinders at one outdoor and one indoor location. A final outdoor experiment attempted to incorporate a variety of temperatures and wind speeds by deploying PAS at nine locations on the Big Island of Hawaii. Each site had one PAS containing one XAD-filled mesh cylinder and another containing two.

Environmental Science: Processes & Impacts front cover image highlighting the article

In the first indoor experiment, the total amount of PCBs accumulated in all segments was not significantly different from the amount accumulated in a mesh cylinder that had not been segmented. In those cylinders that were axially segmented, the amount of PCBs accumulated in the bottom segments was significantly higher than in the upper two segments in office and storage areas, and assumed to have little activity and therefore air turbulence. But this difference was not significant in the mesh cylinder placed in a cargo-loading area, presumably because of the relatively higher level of activity and therefore air turbulence. Similarly, gradients within PAS deployed outdoors were also not as strong, and the samplers exposed to fans indoors showed no significant gradients – strong indications that increased air turbulence allows for more uniform uptake across the length of the sampler.

The effect of heat convection on total accumulation and axial distribution of PCBs was determined to be minor, as was the presence of multiple mesh cylinders within one housing, but only outdoors. Indoors, the amount of PCB accumulated per sampler was significantly lower in those PAS with four mesh cylinders, and the gradient was also steeper.

The final outdoor deployment across varying temperature and wind conditions in Hawaii, which measured accumulation of PCBs, pesticides, polycyclic aromatic hydrocarbons, and polybrominated diphenyl ethers, showed no significant difference in chemical accumulation in PAS with one versus two XAD-filled mesh cylinders. The finding that uptake of SVOCs by XAD PAS is affected very little by the presence of multiple mesh cylinders in one housing in a variety of outdoor conditions means that fewer housings can be used during a given sampling campaign that uses XAD PAS. This augments the low-maintenance nature of this monitoring method, and thus the value of this particular PAS as a tool for monitoring SVOCs in the environment.


To read the full Open Access article, click the link below:

Exploring the role of the sampler housing in limiting uptake of semivolatile organic compounds in passive air sampler
Xianming Zhang, Michelle Hoang, Ying D. Lei, and Frank Wania
Environ. Sci.: Processes Impacts,
2015, 17, 2006-2012
DOI: 10.1039/C5EM00447K

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About the webwriter

Abha Parajulee is a Ph.D. student at the University of Toronto Scarborough. She is interested in water resources and the behavior of organic contaminants in urban environments.

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Naphthalene-eating bacteria

a blog article by Fernando Gomollón-Bel, PhD student at the University of Zaragoza

Most petroleum hydrocarbons are dangerous for the environment and are known to be toxic. These chemicals can cause severe respiratory problems, mutations and cancer. A very particular type of hydrocarbons, known as polycyclic aromatic hydrocarbons (PAHs), represents a serious environmental threat. PAHs can obviously be dangerous when directly inhaled, but they are especially harmful since they can accumulate in water, sediments and soil, taking decades to decompose and thus polluting ecosystems for generations.

A few years ago, some scientists observed that certain species of bacteria had developed, by the means of natural selection, the ability to degrade molecules like hydrocarbons or polymers. Some of these species have evolved to degrade PAHs such as naphthalene, phenanthrene or pyrene, which means that they can be used to treat the waste of certain chemical plants, lowering the amount of these dangerous products released in to the environment.

Using tools like artificial selection or genetic engineering could enhance the efficacy of these bacteria. Moreover, the influence of some external factors may be optimized to improve the conversion of pollutants to non-toxic substances. In this article, recently published in Environmental Science: Processes & Impacts, Professor Mutai Bao and his team studied the effects of supporting bacteria on biodegradable, porous, low-cost materials like semi-coke, walnut shells and activated carbon. Immobilization methods are widely used and accepted by the scientific community because they are versatile and straightforward. Moreover, these systems can be easily cleaned and reused.

Before performing the experiment, scientists had to choose the right species of bacteria. They also had to let them adapt until they were able to properly digest PAHs. To facilitate this, bacteria were fed small amounts of classic carbon sources: glucose, lactose, starch or urea. The ones that received the combination of lactose and PAHs gave the best biodegradation results and were used for the optimization.

After a series of experiments, the authors concluded that immobilized bacteria degrade up to 47% more PAHs than free microbes. Semi-coke was the best support for these microorganisms, followed by walnut shell and activated carbon. In addition to this, they found bacteria to be adaptable to a broad range of pH and salinity. These biodegradation systems could be used in real-life situations such as oil spills in the ocean, where usually other techniques are less productive.

Interested in this research? Click on the link below to read the full article for free*

Biodegradation of different petroleum hydrocarbons by free and immobilized microbial consortia
Tiantian Shen, Yongrui Pi, Mutai Bao, Nana Xu, Yiming Li and Jinren Lu
Environ. Sci.: Processes Impacts, 2015, 17, 2022-2033
DOI: 10.1039/C5EM00318K

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About the webwriter

Fernando Gomollón-Bel is a PhD Student at the ISQCH (CSIC-University of Zaragoza). His research focuses on asymmetric organic synthesis using sugars as chiral-pool starting materials towards the production of fungical transglycosidase inhibitors.

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* Access is free until 18/02/2016 through a registered RSC account.

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Snow soaks up pollutants from engine exhausts

An Environmental Science: Processes & Impacts article highlighted in Chemistry World by Florence Greatrix

Scientists in Canada have shown that snow acts as a sink for nanosized particles and certain organic constituents from car exhausts.

Snow for the experiment was collected from a park in Montreal, where it snows for around 5 months of the year

Air pollution is recognised as a leading environmental driver of cancer deaths, which makes the fate of these toxic and carcinogenic aerosols from car exhausts important for informing changes in emissions and air quality regulations, and technologies, in countries with cold winters.

Anna Lea Rantalainen, an environmental chemist at the University of Helsinki, Finland, says the work raises further questions: ‘It seems that snow is efficient at removing aerosol particles from the air, but what happens after the snow has melted?’ If the sink is temporary, pollutant emissions could increase rapidly in industrialised areas when snow melts. ‘This is not just important for Canada, but other industrial regions like China that emit very diverse compounds, which are subject to transport around the globe,’ cautions Ariya.

Please visit Chemistry World to read the full article.

Role of snow and cold environment in the fate and effects of nanoparticles and select organic pollutants from gasoline engine exhaust*
Yevgen Nazarenko, Uday Kurien, Oleg Nepotchatykh, Rodrigo B. Rangel-Alvarado and   Parisa A. Ariya
Environ. Sci.: Processes Impacts, 2016, Advance Article
DOI: 10.1039/C5EM00616C

*Access is free through a registered RSC account until 25 February 2016 – click here to register

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