Archive for December, 2011

Hot article on evaluating ICP-MS for trace element determination in the workplace

Data on the performance of inductively coupled plasma mass spectrometry (ICP-MS)-which is becoming widely used in the occupational health field for trace elemental analysis, is currently lacking-so in this hot article Kevin Ashley et al. conducted an experiment encompassing 20 labs across Europe, North America and Asia to determine interlaboratory precision estimates.

Read the details and their findings here – the article is free to access for four weeks:

Interlaboratory evaluation of trace element determination in workplace air filter samples by inductively coupled plasma mass spectrometry
Kevin Ashley, Stanley A. Shulman, Michael J. Brisson and Alan M. Howe
DOI: 10.1039/C1EM10695C

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Reggae reggae source

The festival can lead to ammonium levels in the nearby river increasing 210-fold

Here’s a quirky fact. It turns out that a major river polluter in Sweden is the Uppsala Reggae Festival!

Over three days each August, 10,000 reggae-lovers converge on the shores of the River Fyris in Uppsala. Sounds like fun for the festival-goers, but not so much for the fish. You see, at the first sign of rain the contents of the urine soaked festival field get washed into the river (toilet facilities can’t be all that good). If that wasn’t bad enough, any drugs taken by festival-goers (lots of painkillers) are excreted in their urine and end up in the river too. And these biologically active compounds have been known to have an adverse effect on aquatic organisms.

Tests showed that the festival can temporarily result in a higher pharmaceutical input (about 3.4 times greater) into the river than the wastewater treatment plant downstream! But only if it rains.

The recommendation for next year’s festival? Better toilet facilities! I would definitely recommend packing wellies if you’re thinking of going though.

Elinor Richards

Original article posted on the Chemistry World blog

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Be creative, be inspired, be confident

Gregory KorshinGregory Korshin talks to Michael Smith about his passion for environmental science, literature and languages

Gregory Korshin is professor of environmental engineering at the University of Washington, Seattle, US. His interests include environmental electrochemistry, on-line methods to monitor drinking water quality, advanced wastewater treatment operations and environmental chemistry of radionuclides.

What inspired you to become an environmental researcher?

Before I left Russia in 1991, environmental chemistry became something that appealed to me, largely through my reading of English language journals. I felt that I could apply my knowledge of spectroscopy and electrochemistry to solving environmental problems – it was where my heart was and is, because it addresses what we have done or can do to this world – both good and bad.

Why study water?

Water is common to all environmental systems: ground water and surface water processes, radical processes, atmospheric phenomena and so on. It’s a physical and chemical medium for transport of contaminants, always present at interfaces and a daily necessity for all of us. It’s difficult to imagine any quality of life without safe drinking water and sanitation and this drives research, engineering and politics too.

What was your most significant early work in this field?

We discovered simple, frequently linear correlations between changes in absorbance of organic substrates reacting with chlorine and levels of diverse halogenated products formed as a result. Many such compounds are deleterious to health and need to be controlled. We used differential absorbance spectroscopy to probe some of these processes in drinking water and wastewater. We are now measuring fluorescence of natural waters – a beautiful spectroscopic phenomenon that is of interest to many in the environmental community.

Heavy metals are another interest, especially copper and lead in drinking water and using x-ray absorbance spectroscopy to examine the chemical nature of these metals in complex environmental systems.

How far has research on removing contaminants from water progressed?

Water purification is a hugely important and diverse area. Disinfection with chlorine was introduced in Victorian times. When it comes to saving millions of children from waterborne diseases, the Victorian technologies are still very effective.

In the west, we frequently deal with very low concentrations of diverse chemical contaminants that may or may not affect health immediately. In drinking water consumed in developing countries, microbial contaminants determine whether you live or die within hours. Effective, cheap and readily available technologies to control these are important.

Recent developments in water treatment include solar-driven approaches. Their success is tremendously important since they are truly renewable technologies. A range of new materials for water treatment applications are being developed including nanomaterials for removal of trace-level contaminants such as arsenic, but further work is needed. Desalination of sea water is becoming increasingly important.

What’s the next big challenge?

One of several is how to clean contaminated groundwater. This is an incredibly important resource and once a groundwater aquifer has become contaminated, it is very difficult to clean it up. There is currently rapid depletion of erstwhile abundant aquifers.

Trace level contaminants are another important area. There are hundreds of compounds ranging from ibuprofen or synthetic musks to pesticides, cancer drugs and birth control agents. There are currently several views concerning their assumed or documented effects. One hypothesis relates the increased incidence of autism with exposures to such chemicals. Some data indicates that while these compounds may not be so important for adults who have relatively robust endocrine systems, this may not be the case during foetal development or in children.

Many contaminants are endocrine disruptors and their effects on wildlife are very complex and potentially dangerous. Unusual sex changes in fish and invertebrates are observed in rivers without obvious anthropogenic influence, as in many English rivers, as well as in the presence of wastewater effluents, as in the Potomac River in the US. From an ecological point of view, these effects need to be understood, monitored and controlled.

Sometimes we don’t even know what we need to look for. This is because many compounds have not been identified, or cannot be identified because they are part of complex mixtures that cannot be broken down into individual components. These trace contaminants occur at nanogram, or picogram, per litre levels and still induce biological effects. The progress in analytical instrumentation to discover these contaminants has been nothing short of spectacular. Yet, it is still very difficult and expensive to do these studies.

If trace level organics can induce or influence disease in humans or affect life expectancy then this is hugely significant. Already documented effects on fish mean that wastewater needs to be treated more thoroughly than it is done now. However, this should not be viewed as an unwanted complication because wastewater can also be a resource. Phosphorus and ammonia, for example, can be recovered from wastewater and reused as fertiliser.

Which historical character would you most like to meet?

There are several. I have always had tremendous respect for the French tradition of thought. As our Russian poet Pushkin said – that ’sharp Gallic reason’. I admire Laplace and Lagrange who were 18th century French mathematicians and physicists. They were extraordinarily smart people and the culture of science in France then (and now) produced many like this. Joseph Fourier is another one. He created, among other things, a very beautiful mathematical apparatus to analyse very complex phenomena in elegant terms.

Another character that I like a lot is James Clerk Maxwell. His ability to synthesise what relatively little was known at that time about electromagnetism and produce a spectacularly concise set of equations that have been used ever since is astonishing.

So what would your message to a young and aspiring graduate student be?

Be creative, be inspired, be confident. But, ultimately, it is intellectual thirst and curiosity that determines how far one will go.

If you weren’t a scientist, what would you be?

That’s a tough question. It’s a little funny to think about this now but when I was a teenager I was considering a career in the military. I’m not regretting that I didn’t take that up, but it could have been. Actually I do love learning. I love linguistics and history. Linguistics is a great science. I have always been drawn to it. It seeks and finds commonalities in different systems. It has to do with trying to determine what human mind is. I also love optics and light. One of the most fantastically beautiful things in my graduate studies was that I got to design, make and use interesting optical cells, light sources and detectors, and so on. If I hadn’t become a scientist then I would have moved into optical engineering or design.

What do you do when you’re not working?

I dabble in abstract painting. I study languages all the time (at the moment Farsi and Portuguese). I read a lot, often classic Russian poetry and prose. I truly love classic Roman, Italian and French literature. I love history and art. I like socialising with friends and relatives – I have many relatives, we’ve been blessed that way. Travel too: I’ve been to many countries but it’s still not enough.

Read the original Chemistry World article here

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Arctic biting back over mercury pollution

In the Arctic, there are high concentrations of mercury in humans and animals and scientists are investigating how the mercury got there. Mercury has a tendency to accumulate in organisms and bio-magnify (increase in concentration) up through the food chain, so monitoring its levels in the environment is important. In previous investigations, polar bear organs, such as the liver, kidney, hair and blood have been analysed for mercury content, but the results can be inaccurate because soft tissues change throughout the lifetime of the animal.

Polar bear skull

Polar bear teeth from the Natural History Museum at the University of Oslo, Norway, were used as biotracers of temporal changes in mercury pollution exposure. © Aurore Aubail

Now, Aurore Aubail from the National Environmental Research Institute, Denmark, and colleagues from France and Norway, have investigated the temporal trends of mercury using polar bear teeth. Teeth are seen as better materials to use, as contrary to soft tissues, the tooth is not remodelled throughout its life and the mercury is not remobilised.

‘Lots of teeth of various Arctic species are stored in natural history museums of Nordic countries and these institutions are a mine of environmental pollution archives,’ says Aubail. ‘Their collections often go back 100-200 years, which allow researchers to establish time trends of pollutants. Working with these polar bear skulls was really exciting, but extracting the teeth was quite a hard task. It even involved a toolbox!’

The team collected teeth samples from 87 polar bear skulls from the Natural History Museum at the University of Oslo, Norway. They analysed mercury concentrations by solid sample atomic absorption spectrophotometry and the relative abundance of carbon (13C/12C) and nitrogen (15N/14N) stable isotopes by an isotope-ratio mass spectrometer to provide information about potential changes in feeding habits or habitats for polar bears.

The results showed that there has been an overall decrease in mercury concentrations in the Arctic over the last 50 years, which supports earlier results found in polar bear hair from Greenland and human deciduous teeth from Norway. The results from the stable isotope ratios eliminated variations in the feeding or foraging habits as a potential explanation. As the mercury emissions are not sourced from the Arctic, another possible cause is a decrease in the source of the mercury emissions from Europe and North America.

‘Polar bears are an especially useful species for the biomonitoring of contaminants,’ says Sara Moses, an environmental biologist from the Great Lakes Indian Fish and Wildlife Commission, US. ‘Because they are long-lived and sit atop the Arctic food web, they are particularly susceptible to accumulating high levels of mercury in their tissues. As a result, mercury levels in polar bears integrate exposure throughout the food web and provide important information about lower trophic levels as well.’ She adds that teeth are useful monitoring tools because bone is more readily available than soft tissues in many archives and provides a matrix that is relatively stable over time.

Aubail hopes that further investigation into the use of polar bear teeth to study mercury will continue as it is ’still a valuable material that allows us to study long term trends of pollutants’.

Interested? Read Andrew Shore’s full Chemistry World article here or download the JEM paper:

Temporal trend of mercury in polar bears (Ursus maritimus) from Svalbard using teeth as a biomonitoring tissue
Aurore Aubail, Rune Dietz, Frank Rigét, Christian Sonne, Øystein Wiig and Florence Caurant
J. Environ. Monit., 2012, Advance Article
DOI: 10.1039/C1EM10681C

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Devices to help miners breathe easier

New field-portable infrared (IR) devices that can measure mine workers’ exposure levels to silica in coal dust have been designed and tested by scientists in the US.

The inhalation of microscopic particles of crystalline silica is a serious health hazard, and causes a debilitating, and often fatal, condition called silicosis. Miners in particular are at risk of developing this condition.

Currently, samples collected at the field site are sent to a laboratory for testing, often taking weeks to get the results. This time delay between collection and analysis reduces the usefulness of the results in modifying workplace practices to decrease exposure. As the mining workplace is often moving into new geological strata, with changing levels of silica, a faster turnaround in silica measurements is a priority.

Arthur Miller at the National Institute for Occupational Safety and Health, Spokane, and colleagues have based their work on the successful personal dust monitor (PDM), which measures workers’ exposure to coal dust. However, the PDM does not measure silica levels specifically.

Hands holding coal

Coal miners are at risk of developing silicosis by inhaling microscopic particles of crystalline silica in coal dust. © Shutterstock

‘It is our intent to develop a field-portable method for measuring silica that miners can use to get immediate feedback regarding their exposure. Such a device could be used to inform immediate adjustments to the mining process that reduce silica exposures, thereby reducing disease and death due to silicosis,’ says Miller.

The challenge was to design an IR device that could measure quantities of silica at low levels, and get around the interference from other minerals in the air, especially kaolin, using a correction scheme. Two IR devices were tested, one using FTIR spectrometry, the other variable filter array (VFA) IR spectrometry. When compared with the current, laboratory-based method, the FTIR data was found to be comparable.

‘The originality of the approach is to bring an analytical method near to the workplace that enables immediate exposure control in order to prevent occupational lung diseases of miners,’ comments Peter Görner, head of the aerosol metrology laboratory at the National Research Institute on Occupational Safety and Health, Vandoeuvre, France.

The next step is to test the feasibility of the new devices as end-of-shift methods of data collection. Work is still needed to determine the best ways of gathering and handling samples, as well as error analysis, but the hope is that this new technology will one day provide immediate results that can allow miners to adjust the mining process to reduce silica exposure.

Interested? Read Rebecca Brodie’s full Chemistry World article here or download the JEM paper:

Evaluating portable infrared spectrometers for measuring the silica content of coal dust
Arthur L. Miller, Pamela L. Drake, Nathaniel C. Murphy, James D. Noll and John C. Volkwein
J. Environ. Monit., 2012, Advance Article
DOI: 10.1039/C1EM10678C

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Nominations for the 2012 RSC Prizes and Awards now open

Nominations for the 2012 RSC Prizes and Awards close on the 15 January 2012

Our Prizes and Awards represent the dedication and outstanding achievements and are a platform to showcase inspiring science to gain the recognition deserved. Don’t forget to nominate colleagues who have made a significant contribution to advancing the chemical sciences.

View our full list of Prizes and Awards and use the online system to nominate a colleague.

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Detecting airborne flu virus particles and a micronucleus study of water contamination on the cover of Issue 12

Welcome to the final issue of 2011!

On the front cover of Issue 12 we have a hot article from a team at NIOSH on detecting flu virus particles in the air with a two-stage cyclone bioaerosol sampler.  The device is able to separate particles based on size, and may be useful in providing information about the infectivity of the airborne particles, and informing subsequent risk assessments.

Development of an improved methodology to detect infectious airborne influenza virus using the NIOSH bioaerosol sampler
G. Cao, J. D. Noti, F. M. Blachere, W. G. Lindsley and D. H. Beezhold
DOI: 10.1039/C1EM10607D


On the inside front cover is an article from Sílvia Regina Batistuzzo de Medeiros and coworkers on the contamination of a large water reservoir in Brazil with various mutagenic entities such as heavy metals, cyanobacteria and radiation, using the Tradescantia-micronucleus (Trad-MCN) test and cytokinesis-blocked micronucleus (CBMN) assay to confirm the presence of micronuclei in human peripheral blood lymphocytes.

Micronucleus study of the quality and mutagenicity of surface water from a semi-arid region
Anuska Conde Fagundes Soares Garcia, Alexandre Endres Marcon, Douglisnilson de Morais Ferreira, Esdras Adriano Barbosa dos Santos, Viviane Souza do Amaral and Sílvia Regina Batistuzzo de Medeiros
DOI: 10.1039/C1EM10582E

As with all our cover articles these are free to access for 6 weeks.

View the rest of the issue here

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)

Bomb squad plants

Scientists from Puerto Rico have discovered plants that are not only resistant to high levels of TNT but can remove it completely from aqueous media in under 48 hours.

The explosive trinitrotoluene (TNT) is a persistent contaminant that is toxic and mutagenic, and thanks to its use in over 80 per cent of the landmines worldwide, it can be found throughout the globe at military sites and war zones alike.

Caribbean plant and stick of dynamite

Military sites and war zones contaminated with TNT could be cleared by tough Caribbean plants

Samuel Hernández-Rivera and co-workers at the University of Puerto Rico-Mayagüez investigated the ability of three Caribbean plants – Rubia tinctorum, Lippia dulcis and Spermacoce remota – to remove TNT. Plantlets of each were added to flasks containing solutions of TNT and samples were taken at timed intervals for high performance liquid chromatography analysis, with a flask containing just the TNT solution used for comparison.

R. tinctorum and L. dulcis removed nearly 100 per cent of the TNT from the liquid medium, showing a roughly 10-fold increase in the rate of TNT removal compared to loss by evaporation in the control flask. What is even more significant is that S. remota, under identical conditions, can completely remove TNT from the media in under 48 hours.

Hernández-Rivera and his colleague Fernando Souto-Bachiller say that the main mechanism for TNT removal from the media is via adsorption through the roots, but once adsorbed, S. remota seems to have a different mechanism of action. They say that this result was initially attributed to either ‘a possible enzyme exudate, which would then be responsible for TNT degradation, or a symbiotic relationship between the plant roots and a persistent microorganism, fungus or bacteria.’ Future work within the group will involve isotopically labelling TNT to investigate the enhanced behaviour of S. remota.

Tomás E. Macek from the Institute of Organic Chemistry and Biochemistry, Czech Academy of Sciences, Czech Republic, says that the work deals with an ‘important topic and that detoxification of contaminated sites is a global problem’, but ‘there is much to be done to allow effective exploitation in the field’.

Hernández-Rivera says that ongoing experiments are focused on using the plants in TNT contaminated soil, and although ‘physical and biochemical processes in soils are much more complicated’, initial results look promising.

Interested? Read James Anson’s full Chemistry World article here or download the JEM paper:

TNT removal from culture media by three commonly available wild plants growing in the Caribbean
Sandra N. Correa-Torres, Leonardo C. Pacheco-Londoño, Eduardo A. Espinosa-Fuentes, Lolita Rodríguez, Fernando A. Souto-Bachiller and Samuel P. Hernández-Rivera
J. Environ. Monit., 2012, Advance Article
DOI: 10.1039/C1EM10602C

Digg This
Reddit This
Stumble Now!
Share on Facebook
Bookmark this on Delicious
Share on LinkedIn
Bookmark this on Technorati
Post on Twitter
Google Buzz (aka. Google Reader)