Archive for the ‘HOT Articles’ Category

Chlorinated compounds form in tea and coffee

Tea and coffee are the most consumed beverages in the world, but a new study has discovered some unexpected chemistry occurring in our cups.

Contrary to popular belief, boiling the water only removes around 20% of chlorine © Shutterstock

Chlorine is added to water as part of the disinfection process, with a residual amount remaining in the treated water to supress microbial growth. This chlorine reacts with organic molecules in the water to produce chlorinated chemicals known as disinfection byproducts (DBPs), such as chloroform.

Nikolai Kuhnert from Jacobs University, Germany, conducts research on compounds in tea and coffee. He advocates further research into the effects processing has on our food. ‘It illustrates further how little we know on the chemistry of food processing that significantly alters the chemical composition of our daily diet, producing both novel compounds with adverse or beneficial properties for human health.’



Read the full article in Chemistry World!

Read the original research paper in Environmental Science: Water Research & Technology:
Emerging investigators series: formation of disinfection byproducts during the preparation of tea and coffee

Tom Bond, Seeheen C. Tang, Nigel Graham and Michael R. Templeton
Environ. Sci.: Water Res. Technol.
, 2016, Advance Article
DOI:
10.1039/C5EW00222B

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Emerging Investigators Series author: Tom Bond

Tom Bond is a Junior Research Fellow (JRF) in the Environmental and Water Resource Engineering (EWRE) section at Imperial College London. His research is focused on the role aquatic chemistry can play in identifying and removing hazardous contaminants during water and wastewater engineering treatment processes.

Although he has spent most of his research career in engineering departments, his first degree was in chemistry and he is interested in synergistic interactions between the two disciplines. He holds a PhD on the treatment of disinfection byproduct precursors and MSc in Water and Wastewater Engineering, both from Cranfield University, and a first class honours degree (MSci) in chemistry from Bristol University.

Read Tom’s Emerging Investigators article ‘formation of disinfection byproducts during the preparation of tea and coffee’ here.


– How has your research evolved from your first to your most recent article?
My first article was on disinfection byproducts, as is this latest one. However, in between I have also worked on lots of different areas, so hopefully I am now knowledgeable about a wider range of research topics then when I started in research.

– What aspect of your research are you most excited about at the moment?
In general, I am excited by having the freedom to work on different topics and pursue things which interest me. If I am able to make any contributions to improving the public health impact of drinking water then that would be even better.

– Your paper discusses an issue that potentially affects most of us. How did you come up with this idea?
I was reading a thesis from a student at Imperial College, in which was made an incidental comment that tea and coffee represent potential sources of disinfection byproducts. And I thought, That’s an interesting idea actually. After looking in the literature, I was quite surprised to find that this was not something that had been looked at much detail previously. This made it seem like something that would be worth proposing as an MSci research project, which turned out to be the case, especially as an excellent student selected it (Seeheen Tang).

– What was your biggest challenge during this research?
We had some technical challenges with the laboratory work along the way. The biggest was that I initially wanted to undertake a liquid-liquid extraction on the chlorinated tea and coffee samples prior to analysing for disinfection byproducts by gas chromatography. This is a standard method in the drinking water research.

However, as we found out, when you try extracting tea or coffee into an organic solvent you get a horrible frothy mess, which is hopeless for extracting anything from. After trying some alternatives, I ended up sending some samples to an external lab for trihalomethane analysis using a headspace gas chromatography method. This relies on heating the sample to separate the volatile trihalomethanes, rather than extracting them.

– How did you find out about Environmental Science: Water Research & Technology and how was your experience?
It was mentioned to me by colleagues at Imperial, while I have also seen it advertised at conferences I have attended. The editorial and peer review process was very efficient in the case of this article.

– How do you spend your spare time?
In no particular order: walking/hiking, going to the pub, eating out and birdwatching. The last of these is my biggest passion, even if I probably spend more time on the other activities mentioned.

– If you could not be a scientist, but could be anything else, what would you be?
A writer, although I am not sure of which type. Of the various enjoyable aspects of working in a university, writing is the part I like most. And it would intrigue me to try writing in a different style to that required by science/academia. As a secondary alternative, being a professional footballer would be ok (!), although I fear that I am already too old, not to mention unskilled, for that possibility.

– Can you share one piece of career-related advice or wisdom with other early career scientists?
Try to improve a variety of aspects of your CV, rather than concentrating on one or two, as this should give you more opportunities in the future. It also helps if you know where you want to go in your career, as then you can plan strategically what is needed to get there.

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Electrodes enhance H2 production and sludge decomposition in microbial electrolysis

Using microbial electrolysis for hydrogen production

Microbial electrolysis is a method that generates methane or hydrogen from organic material by applying an electric current. Hydrogen is particularly explored as an alternative fuel for passenger vehicles, either in fuel cells to power electric motors or burned in internal combustion engines.

Microbial Electrolysis Cell

A schematic of the general process in a Microbial Electrolysis Cell - here with plant waste as initial resource (Image by Zina Deretsky, National Science Foundation, available as public domain: http://images.dailytech.com/nimage/6590_large_biohydrogen_h.jpg)

Microbial electrolysis and waste activated sludge

A Microbial electrolysis cell is capable of producing hydrogen from waste water or waste biomass. Waste activated sludge (WAS), a byproduct of biological wastewater treatment processes, is an example of how to produce hydrogen (H2) via the method of microbial electrolysis.

The hydrogen from anaerobic fermentation is produced by hydrogen producing bacteria (HPB) and consumed by hydrogen consuming bacteria (HCB) such as methanogens. Unfortunately the H2 production in anaerobic digestion of sludge is often low since the waste sludge have a limited carbohydrate source available for HPB.

The central process of microbial electrolysis cells is when exoelectrogens oxidise the substrates and release an electron to the anode, and then the electron is accepted by H+ to produce hydrogen at the cathode. This process requires a voltage supply to overcome the energy barrier between the two electrodes –although the hydrogen production from waste sludge might increase in a microbial electrolysis cell, the energy efficiency is low because of the extra voltage applied.

Low hydrogen production from anaerobic digestion of sludge has greatly limited the application of biological hydrogen-producing technology.

New research

A recent study published in Environmental Science: Water Research & Technology by Yinghong, Liu and Zhang sheds new light on the topic. By installing a Fe/graphite electrode into an anaerobic digester, the hydrogen production from waste sludge was improved. The electrode accelerated the decomposition of the sludge and also increased the production of short-chain fatty acids. The electric-anaerobic system also inhibited the occurrence of methanogenesis, which led to quite low methane production.

The study by Zhang and colleagues is unique since this was the first time that net energy was harvested from WAS in a hydrogen-producing microbial electrolysis cell with a cost-effective electrode.

Interested in this research? You can read the full paper for free* using the link below:

Enhancement of sludge decomposition and hydrogen production from waste activated sludge in a microbial electrolysis cell with cheap electrodes
Feng Yinghong, Yiwen Liu and Yaobin Zhang
Env. Sci: Water Res. Technol.
2015, advance article
DOI
:10.1039/c5ew00112a

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About the webwriter

Jesper Agrelius is a MSc student in Environmental Science at Linköping University, Sweden. His main interests regards environmental science, especially climate change and biogeochemistry. You can follow him on Twitter @JesperAgrelius.

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Admit it – we already drink recycled water

I heard someone ask recently: Has the same water been going around since the dinosaurs peed into it? Intriguing, especially when we think about it in the context of water reuse. Climate change is causing more extreme droughts and floods. As our growing population struggles for equitable allocation and access to limited freshwater resources, we are faced today with an urgent need to diversify our water portfolio.

Policy innovations for recycled water – The long view. Effective tackling of water security challenges demands policy innovations. We wholeheartedly endorse policies and technological innovations related to rainwater harvesting, fog catching or decentralized solar-enabled water purification systems (e.g., the Watercone). But using recycled water seems yucky, and efforts to encourage the use of recycled water have received some strong pushback in the past.

The recent droughts in California, however, have resuscitated the discussions about water recycling in the United States. But how successfully do water recycling policies survive the ebbs and flows of environmental stresses, political will, and public memory? Dr. John C. Radcliffe’s recent article gives new insight into this question. The article outlines the successes and shortcomings of Australia’s water recycling over the last two decades, when the prolonged “Millennium Drought” in the 2000s made it necessary for Australia to adopt alternative strategies for water security, and to develop new policies for potable uses of recycled water. Things looked promising for Australia’s long-term water sustainability… but then the droughts ended.

Complacency + the Yuck factor = Terrible, no-good, very bad self-inflicted water crisis. Our resolve to address water sustainability issues and to implement long-term solutions is often tested – ironically – when the threat of water scarcity temporarily fades. As Radcliffe notes, “The end of the drought in eastern Australia has distanced community, industry and government policy focus from strengthening the security of water supply (at almost any cost) to one of pursuing economic efficiency and containing consumers’ water charges and prices.” And the Yuck factor about toilet-to-tap policies doesn’t help.

Blue Gold slipping through our fingers. The poignant opening lines of an Urdu ghazal from yesteryears croon: Duniya jise kehte hain / jaadoo ka khilona hai / Mil jae toh mitti hai / kho jae toh sona hai. Meaning: This world is magical. Here, when we are fortunate to have something, we treat it like dirt (mitti). But as it begins to slip away, it becomes precious like gold (sona). Opportunities to successfully meet our water challenges are shrinking. That glass of water sitting on the toilet seat on the right has been rightly called Blue Gold. And it is slipping away.

Today, while reassessing our water policies while threats to our water security loom in the horizon, let us not forget the lessons that hindsight has to offer.

You can access the full paper for free* using the link below:

Water recycling in Australia – during and after the drought
John C. Radcliffe
Environ. Sci.: Water Res. Technol., 2015,1, 554-562
DOI: 10.1039/C5EW00048C




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About the webwriter

Paramjeet Pati is a PhD Candidate at the Virginia Tech Center for Sustainable Nanotechnology (@VTSuN).
You can find more articles by him in the VTSuN blog, where he writes using the name coffeemug.

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*Access is free through a registered RSC account – click here to register

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Flushing advice is flawed

Instructions given to the public by water companies and other authorities in the aftermath of chemical contaminations are inconsistent and not validated by science. So say scientists in the US who are developing models to understand complex plumbing systems to ensure consumers get the best guidance on how to regain access to safe drinking water.

In the last two years, more than a million people in Canada and the US have been affected by similar incidents. Large-scale water contamination incidents are not uncommon, yet there has been little research into purification procedures.


Read the full article in Chemistry World!


Read the original research paper in Environmental Science: Water Research & Technology:
Decontaminating chemically contaminated residential premise plumbing systems by flushing

K. S. Casteloes, R. H. Brazeau and A. J. Whelton
Environ. Sci.: Water Res. Technol.
, 2015, Advance Article
DOI:
10.1039/C5EW00118H, Paper


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Analyzing prioritized indicator compounds of TOrC in wastewater using rapid direct injection method

Trace organic compounds (TOrCs) – potential risks to public health

Running water from tap

TOrCs in drinking water can be present at low levels - with potential harmful risk to public health.

To evaluate drinking water quality, one needs to consider physical, chemical and microbiological parameters. Physical and chemical parameters can be heavy metals, turbidity and trace organic compounds for instance, whilst viruses, parasites and bacteria are microbiological parameters.

Trace organic compounds originate from pesticides, pharmaceuticals, industrial compounds, chlorinated flame retardants and consumer product chemicals such as household chemicals, amongst others. TOrCs in water can be present at low levels but with potential harmful risk to public health. Due to the potential harmful risk, TOrCs are highlighted in the World Health organization (WHO) guidelines for drinking water quality.

Diving into the unknown

Wastewater discharge is the main contributor to TOrCs in drinking water, one reason being that these compounds are poorly attenuated in conventional water treatment processes. There are several hundred identified TOrCs, with numerous new organic chemicals being released daily. To monitor all these compounds is unfeasible, which is the reason we need to establish prioritized indicator compounds.

Rapid direct injection methods

By doing a detailed literature review and using a scoring system, Tarun Anumol and colleagues from University of Arizona present new research where they established 20 prioritized indicator TOrC which can be detected with a rapid direct injection method.

A rapid direct injection method for examining wastewater is beneficial for many reasons:
  • Minimal sample preparation reduces the risk for contamination – conventional analysis of these compounds is challenging with various sample extraction and several human intervention steps, which increase contamination risks and reduce accuracy and reproducibility.
  • Rapid direct injection methods increase efficiency and  functions with low sample volume – the method only needs one injection and < 100 μL sample volume while providing reporting limits of 3-39 ng L-1(302 ng L-1 for sucralose), minimal sample preparation increases efficiency.

By analyzing effluent from four different wastewater treatment plants, the 20 prioritized TOrC were detected in three out of four effluents. Certain of the prioritized TOrCs are also effective indicators for seasonal variability, consumption patterns and treatment process efficiency.

Trace organic compounds to waste-water discharge to drinking water

Trace organic compounds are poorly attenuated in conventional water treatment processes and wastewater discharge is the main contributor to TOrCs in drinking water.

The research by Tarun Anumol and colleagues provides knowledge and guidance towards effective wastewater monitoring schemes to detect trace organic compounds, an important piece of the puzzle towards increased drinking water quality.

You can read the full paper for free* using the link below:

Tarun Anumol, Shimkin Wu, Mauricius Marques dos Santos, Kevin D. Daniels and Shane A. Snyder.
Env. Sci: Water Res. Technol. 2015, Advance Article.
DOI: 10.1039/c5ew00080g.

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About the webwriter

Jesper Agrelius is a MSc student in Environmental Science at Linköping University, Sweden. His main interests regards environmental science, especially climate change and biogeochemistry. You can follow him on Twitter @JesperAgrelius.

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*Access is free through a registered RSC account.

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Emerging Investigators Series author: Krista Wigginton

Krista Rule Wigginton received her Ph.D. in Environmental Engineering from Virginia Tech under P. J. Vikesland (2008). She conducted postdoctoral research at École Polytechnique Fédérale de Lausanne (2009–2010) under T. Kohn. She was an Assistant Professor of Environmental Engineering at the University of Maryland (2011–2012) and is now an Assistant Professor of Environmental Engineering and the Borchardt and Glysson Water Treatment Faculty Scholar at the University of Michigan. Her main research interests involve the detection and fate of emerging biological contaminants in drinking and wastewater treatment.

Read Krista’s Emerging Investigators article ‘the source and fate of pandemic viruses in the urban water cycle’ here.

How has your research evolved from your first to your most recent article?
My first article as an undergraduate researcher was on the synthesis of fluorinated organic compounds. This paper is on emerging viruses in the water environment. So my research has definitely evolved since I was an undergraduate student! I still consider myself an organic chemist, but now I study how viruses, which are essentially large organic molecules, behave in natural and engineered environments.

What aspect of your research are you most excited about at the moment?
I’m really enjoying the work we’re doing on environmental viruses. I started working with viruses towards the end of my Ph.D., and I’m still fascinated by them. There is so much we don’t know about the types, concentrations, and fate of human viruses in the environment. Right now, we have projects on human noroviruses, poliovirus, and coronaviruses, and we’re even starting a collaboration studying pig viruses.

What do you see as the biggest challenge or threat to global water supplies?
There are so many challenges to global water supplies, but so much is routed in human behavior. We know where to find water, we know the basics of how to clean water, and we know how to conserve water. The big challenge for scientists and engineers lies in helping the public and policy makers put this knowledge to practice.

In which upcoming conferences may our readers meet you?
I’m co-organizing a session on microorganism fate and detection at the upcoming ACS meeting in Boston. I’ll also be giving a talk on enveloped viruses at the IWA International Symposium of Health-Related Water Microbiology in Lisbon this September.

How do you spend your spare time?
Right now, most of my spare time is dedicated to my two children Lucille (3 years) and Max (1 year). They help me keep my life balanced.  I like to cook, garden, and my guilty pleasure is binge watching TV seasons on Netflix.

Which profession would you choose if you were not a scientist?
Hmm, that’s tough. I took flying lessons in high school and really enjoyed it, so I’ll just say pilot.

Can you share one piece of career-related advice/wisdom with other early career scientists?
With so few academic positions available for scientists and engineers, I think early career researchers need to be open to and prepared for more than one career path. I tried to keep as many doors open as possible all the way up to the point when I received an offer for an assistant professor position. I love my job, but I think I could have been just as happy working in consulting or for the government. Having options is good.

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Beach sand – key player in coastal beach water management

Beach sand – not just for sunbathers

After hearing the word “beach”, many people automatically think of sunbathing, long walks near the sea, building sand castles and throwing Frisbees – recreation at its finest. Beaches are one of the most visited ecosystems for human recreation and are of high importance for regional economies, in many cases especially for tourism. Beaches and recreational bathing waters are highlighted by the World Health Organization (WHO) as important for health and wellbeing. But did you know that beaches, and in particular the beach sand itself, also plays a vital part in coastal beach water management?

Worldwide public use of water for recreational purposes and recreational activities that involves water have increased over the years. But this also means that recreational exposure to pathogens in the water environment also increases.

Fecal contamination of coastal waters

There are many different kinds of contaminants that humans can be exposed to with regard to water, such as protozoas and trematodas, bacterias and viruses. Current recreational water management practices tend to focus primarily on the beach water itself, excluding the impacts of beach sand on water quality. A wider approach is needed to fully understand how other components of the beach system can influence the water quality.

New research by Qian Zhang, Xia He and Tao Yan, from the University of Hawaii at Manoa, studied what role beach sand has in coastal beach water management.

Beach sand is often highlighted for its negative impact because it functions as a potential source and reservoir to fecal indicator bacteria, often showing higher levels than the surrounding water. This could cause chronic water quality deterioration and hamper proper health risk assessment. However, to get full knowledge of the beach system, we also need to understand the positive impacts that beach sand can have on water quality.

By using microcosms, small experimental and simplified ecosystems, Zhang and colleagues have examined how subtidal beach sand can enhance the decay of fecal bacteria and which underlying mechanisms contribute to the process.

Indigenous microbiota – a significant factor in bacterial decay

The study identified that beach sand indigenous microbiota was the major factor in bacterial decay rates, and showed that higher indigenous microbiota corresponded to faster bacterial decay. This research proved that beach sand actively facilitates the removal of fecal bacteria, which goes beyond the traditional perception of beach sand only serving for contaminant adsorption and retention.

The study shows that beach sand have other functions than just being for recreation, it also contributes significantly to water quality. Thanks to the research findings from Zhang and colleagues, beach water management practices can be improved to include beach sand and other functions of natural processes in beach systems, which would be a more inclusive systems approach. This would also enhance our understanding and management of recreational exposure to pathogens in water.



You can read the full paper for free* using the link below:

Impact of indigenous microbiota of subtidal sand on fecal indicator bacteria decay in beach systems: a microcosm study
Qian Zhang, Xia He and Tao Yan.
Environ. Sci: Water Res. Technol., 2015, 1, 306-315.
DOI: 10.1039/c5ew00004a

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About the webwriter

Jesper Agrelius is a MSc student in Environmental Science at Linköping University, Sweden. His main interests regards environmental science, especially climate change and biogeochemistry. You can follow him on Twitter @JesperAgrelius.

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*Access is free through a registered RSC account.

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Purity and character of water

The purity of water can mean different things to different people. When I call a glass of water pure, am I saying that it’s safe to drink, or clean enough to be labeled as “research-grade”, or do I mean that it has two molecules of hydrogen for every molecule of oxygen and absolutely nothing else? And where can we find the purest, cleanest water in nature?

Pure as the driven snow?

Image adapted from Wikipedia

It ain’t pure if it’s natural. It ain’t natural if it’s pure. As rain and snow make their way to the earth, they dissolve particles, minerals and gases. Once on the ground as surface water from rain and snowmelt, the water continues to gather dissolved and suspended materials (including microorganisms), as it flows over the soil and the rocks. Rainwater and snow also contain many pollutants and may not be appropriate for drinking without treatment. So, the next time someone tries to sell you a bottle of “pure natural water”, ask where that pure water came from, because, as Machell et al. say in a recent paper, “Pure water does not exist in nature…”.

If it ain’t pure, is it safe? Indeed this is a key question that links drinking water with public health issues. Very few drinking water quality parameters require legal compliance. The Drinking Water Directive in Europe and the Safe Drinking Water Act in the United States are notable exceptions. But most drinking water quality parameters serve merely as guidelines, rather than specific requirements that can be enforced by law.

Due to increasing stresses on our water infrastructure, we are now forced to look for alternative sources of water (such as wastewater reuse, rainwater harvesting and dual distribution systems for potable and non-potable uses).  So, a clear understanding of purity becomes even more important when these alternative sources are used to provide fit-for-purpose or safe-to-drink water.

Ultrapure water - not good for making tasty ice

Image adapted from Wikipedia

“If I find the world’s cleanest, purest water, I can make the world’s tastiest ice.”, said David Rees in an episode of Going Deep (National Geographic).  But he was disappointed after tasting ultrapure water – i.e., water devoid of any impurity. (Perhaps he was also disappointed that he was not allowed do a keg stand, and had to drink the water from a flask.)

In fact, ultrapure water is quite expensive and is an aggressive solvent used semiconductor industry for cleaning wafers – definitely not meant for making the world’s tastiest ice. Rees succinctly summed up the issue: “Don’t overpurify your water – minerals and salts add character.”

An old saying goes: “Water which is too pure has no fish.” Today, we need a more nuanced understanding about water purity to assess the tradeoffs between the cost of treating water and acceptable levels treatment for providing safe drinking water. Indeed, as Machell et al. say, “Water purity is a vague term… Safe water is economical and attainable, whereas pure water is not.”


How does this idea of water purity govern environmental monitoring and risk assessment? Find out by reading the full paper for free* using the link below:

Drinking water purity – a UK perspective
John Machell, Kevin Prior, Richard Allan and John M. Andresen
Environ. Sci.: Water Res. Technol., 2015,1, 268-271
DOI: 10.1039/C5EW90006A, Forum

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About the webwriter

Paramjeet Pati is a PhD Candidate at the Virginia Tech Center for Sustainable Nanotechnology (@VTSuN).
You can find more articles by him in the VTSuN blog, where he writes using the name
coffeemug.

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*Access is free through a registered RSC account.

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Disinfection by-products during ballast water treatment

Maritime transportation is vital for local and global economies and international trade, but it also causes many environmental problems.

Ballast water – safe and efficient, but also harmful

Water has been used as ballast to stabilize ships since the introduction of steel vessels during the last centuries. Ballast water provides stability and manoeuvrability and also compensates for weight changes in cargo loads, fuel and water consumption, among others. Ballast water is crucial for efficient and safe shipping operations, however it also has environmental downsides.

A reason for concern

The transportation of invasive species via ballast water is a serious ecological threat and have received a lot of focus during recent years. There is an International convention for the Control and Management of Ships’ Ballast water and sediment (BWM) that was adopted 2004, which promotes procedures and standards to control and manage the ballast water.

Ballast water management technologies is seen as a key factor in combating ecological and health risks of ballast water. There are several ways to treat ballast water, either mechanical, physical or chemical methods, or in combination. These treatment methods are seen as a response to the ecological threat of invasive species, but the methods themselves also come with certain environmental risks. Chemical treatment of ballast water can result in formation of disinfection by-products, which are thought to have an impact on health.

Formation of disinfection by-products in ballast water treatment
New research by Amisha Shah and colleagues have observed the extent of disinfection by-products (DBP) formation during chemical treatment of ballast water. Chlorine, ozone, peracetic acid (PAA) and chlorine dioxide, predominantly used in ballast water management systems in this order from the former to the later, where used to examine and assess DBP formation in several ballast water types such as seawaters, brackish waters, synthetic- and man-made freshwater. Our knowledge of the potential formation of DBP in saline water is limited and therefore is it important to conduct this type of studies, since many ballast waters often are saline.

Ballast water – hitch-hiking invasive species. Source: http://globallast.imo.org/

Studied DBPs include trihalomethanes (THMs), bromate, and haloacetic acids (HAAs). Approximately 50% of the formation of DBPs occurred within 24 hours of the usual 5 day ballast water treatment holding time. The findings highlight that our understanding of DBP formation in freshwater systems can be partially transferred to saline waters.

The research show several factors that influence DBP formation in saline waters: salinity, dissolved organic matter (DOM) type/concentration, oxidant type/dose and temperature. Particularly salinity seems to influence the bromide concentration and brominated DBPs dominated in high bromide-containing waters. Temperature shows diverse and limited influence on DBP formation: TBAA and CHBr3 formation was not affected by temperature, whereas DBAA and bromide formation decreased following a disminution in temperature.

Thanks to this study, important factors in DBP formation have been examined so ballast water treatment disinfection strategies can be optimized to limit DBP formation and discharge in our waters – one of many steps towards a sustainable transport system.

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You can read the full paper for free* using the link below:

Formation of disinfection by-products during ballast water treatment with ozone, chlorine, and peracetic acid: influence of water quality parameters
Amisha D. Shah, Zheng-Qian Liu, Elisabeth Salhi, Thomas Höfer, Barbara Werschkund and Urs von Gunten
Environ. Sci.: Water Res. Technol., 2015, Advance Article
DOI: 10.1039/C5EW00061K

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About the webwriter

Jesper Agrelius is a MSc student in Environmental Science at Linköping University, Sweden. His main interests regards environmental science, especially climate change and biogeochemistry. You can follow him on @JesperAgrelius.

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*Access is free through a registered RSC account.

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