Tag Archives: Mark Wiesner

Gold nanoparticles not always always biologically stable

It’s usually silver nanoparticles (with a nod to titanium dioxide as another problem nanoparticle) which star in scenarios regarding environmental concerns, especially with water. According to an Aug. 28, 2018 news item on Nanowerk, gold nanoparticles under certain conditions could also pose problems,

It turns out gold isn’t always the shining example of a biologically stable material that it’s assumed to be, according to environmental engineers at Duke’s Center for the Environmental Implications of NanoTechnology (CEINT).

In a nanoparticle form, the normally very stable, inert, noble metal actually gets dismantled by a microbe found on a Brazilian aquatic weed.

While the findings don’t provide dire warnings about any unknown toxic effects of gold, they do provide a warning to researchers on how it is used in certain experiments.

Here’s an image of one of the researchers standing in the test bed where they made their discovery (the caption will help to make sense of the reference to mesocosms in the news release, which follows,,

Mark Wiesner stands with rows of mesocosms—small, manmade structures containing different plants and microorganisms meant to represent a natural environment with experimental controls. Courtesy: Duke University

An August 28, 2018 Duke University news release (also on EurekAlert) by Ken Kingery, which originated the news item, provides more detail about gold nanoparticle instability,

CEINT researchers from Duke, Carnegie Mellon and the University of Kentucky were running an experiment to investigate how nanoparticles used as a commercial pesticide affect wetland environments in the presence of added nutrients. Although real-world habitats often receive doses of both pesticides and fertilizers, most studies on the environmental effects of such compounds only look at a single contaminant at a time.

For nine months, the researchers released low doses of nitrogen, phosphorus and copper hydroxide nanoparticles into wetland mesocosms [emphasis mine]– small, manmade structures containing different plants and microorganisms meant to represent a natural environment with experimental controls. The goal was to see where the nanoparticle pesticides ended up and how they affected the plant and animal life within the mesocosm.

The researchers also released low doses of gold nanoparticles as tracers, assuming the biologically inert nanoparticles would remain stable while migrating through the ecosystem. This would help the researchers interpret data on the pesticide particles that partly dissolve by showing them how a solid metal particle acts within the system.

But when the researchers went to analyze their results, they found that many of the gold nanoparticles had been oxidized and dissolved.

“We were taken completely by surprise,” said Mark Wiesner, the James B. Duke Professor and chair of civil and environmental engineering at Duke. “The nanoparticles that were supposed to be the most stable turned out to be the least stable of all.”

After further inspection, the researchers found the culprit — the microbiome growing on a common Brazilian waterweed called Egeria densa. Many bacteria secrete chemicals to essentially mine metallic nutrients from their surroundings. With their metabolism spiked by the experiment’s added nutrients, the bacteria living on the E. densa were catalyzing the reaction to dissolve the gold nanoparticles.

This process wouldn’t pose any threat [emphasis mine] to humans or other animal species in the wild. But when researchers design experiments with the assumption that their gold nanoparticles will remain intact, the process can confound the interpretation of their results.

“The assumption that gold is inert did not hold in these experiments,” said Wiesner. “This is a good lesson that underscores how real, complex environments, that include for example the bacteria growing on leaves, can give very different results from experiments run in a laboratory setting that do not include these complexities.”

Here’s a link to and a citation for the paper,

Gold nanoparticle biodissolution by a freshwater macrophyte and its associated microbiome by Astrid Avellan, Marie Simonin, Eric McGivney, Nathan Bossa, Eleanor Spielman-Sun, Jennifer D. Rocca, Emily S. Bernhardt, Nicholas K. Geitner, Jason M. Unrine, Mark R. Wiesner, & Gregory V. Lowry. Nature Nanotechnology (2018) DOI: https://doi.org/10.1038/s41565-018-0231-y Published

This paper is behind a paywall.

Silver nanoparticles and wormwood tackle plant-killing fungus

I’m back in Florida (US), so to speak. Last mentioned here in an April 7, 2015 post about citrus canker and zinkicide, a story about a disease which endangers citrus production in the US, this latest story concerns a possible solution to the problem of a fungus, which attacks ornamental horticultural plants in Florida. From a May 5, 2015 news item on Azonano,

Deep in the soil, underneath more than 400 plant and tree species, lurks a lethal fungus threatening Florida’s $15 billion a year ornamental horticulture industry.

But University of Florida plant pathologist G. Shad Ali has found an economical and eco-friendly way to combat the plant destroyer known as phytophthora before it attacks the leaves and roots of everything from tomato plants to oak trees.

Ali and a team of researchers with UF’s Institute of Food and Agricultural Sciences, along with the University of Central Florida and the New Jersey Institute of Technology, have found that silver nanoparticles produced with an extract of wormwood, an herb with strong antioxidant properties, can stop several strains of the deadly fungus.

A May 4, 2015 University of Florida news release, which originated the news item, describes the work in more detail,

“The silver nanoparticles are extremely effective in eliminating the fungus in all stages of its life cycle,” Ali said. “In addition, it has no adverse effects on plant growth.” [emphasis mine]

The silver nanoparticles measure 5 to 100 nanometers in diameter – about one one-thousandth the width of a human hair. Once the nanoparticles are sprayed onto a plant, they shield it from fungus. Since the nanoparticles display multiple ways of inhibiting fungus growth, the chances of pathogens developing resistance to them are minimized, Ali said. Because of that, they may be used for controlling fungicide-resistant plant pathogens more effectively.

That’s good news for the horticulture industry. Worldwide crop losses due to phytophthora fungus diseases are estimated to be in the multibillion dollar range, with $6.7 billion in losses in potato crops due to late blight – the cause of the Irish Potato Famine in the mid-1800s when more than 1 million people died – and $1 billion to $2 billion in soybean loss.

Silver nanoparticles are being investigated for applications in various industries, including medicine, diagnostics, cosmetics and food processing.  They already are used in wound dressings, food packaging and in consumer products such as textiles and footwear for fighting odor-causing microorganisms.

Other members of the UF research team were Mohammad Ali, a visiting doctoral student from the Quaid-i-Azam University, Islamabad, Pakistan; David Norman and Mary Brennan with the University of Florida’s Plant Pathology-Mid Florida Research and Education Center; Bosung Kim with the University of Central Florida’s chemistry department; Kevin Belfield with the College of Science and Liberal Arts at the New Jersey Institute of Technology and the University of Central Florida’s chemistry department.

Ali’s comment about silver nanoparticles not having any adverse effects on plant growth is in contrast to findings by Mark Wiesner and other researchers at  Duke University (North Carolina, US). From my Feb. 28, 2013 posting (which also features a Finnish-Estonia study showing no adverse effects from silver nanoparticles  in crustaceans),

… there’s a study from Duke University suggests that silver nanoparticles in wastewater which is later put to agricultural use may cause problems. From the Feb. 27, 2013 news release on EurekAlert,

In experiments mimicking a natural environment, Duke University researchers have demonstrated that the silver nanoparticles used in many consumer products can have an adverse effect on plants and microorganisms.

The main route by which these particles enter the environment is as a by-product of water and sewage treatment plants. [emphasis] The nanoparticles are too small to be filtered out, so they and other materials end up in the resulting “sludge,” which is then spread on the land surface as a fertilizer.

The researchers found that one of the plants studied, a common annual grass known as Microstegium vimeneum, had 32 percent less biomass in the mesocosms treated with the nanoparticles. Microbes were also affected by the nanoparticles, Colman [Benjamin Colman, a post-doctoral fellow in Duke’s biology department and a member of the Center for the Environmental Implications of Nanotechnology (CEINT)] said. One enzyme associated with helping microbes deal with external stresses was 52 percent less active, while another enzyme that helps regulate processes within the cell was 27 percent less active. The overall biomass of the microbes was also 35 percent lower, he said.

“Our field studies show adverse responses of plants and microorganisms following a single low dose of silver nanoparticles applied by a sewage biosolid,” Colman said. “An estimated 60 percent of the average 5.6 million tons of biosolids produced each year is applied to the land for various reasons, and this practice represents an important and understudied route of exposure of natural ecosystems to engineered nanoparticles.”

“Our results show that silver nanoparticles in the biosolids, added at concentrations that would be expected, caused ecosystem-level impacts,” Colman said. “Specifically, the nanoparticles led to an increase in nitrous oxide fluxes, changes in microbial community composition, biomass, and extracellular enzyme activity, as well as species-specific effects on the above-ground vegetation.”

Getting back to Florida, you can find Ali’s abstract here,

Inhibition of Phytophthora parasitica and P. capsici by silver nanoparticles synthesized using aqueous extract of Artemisia absinthium by Mohammad Ali, Bosung Kim, Kevin Belfield, David J. Norman, Mary Brennan, & Gul Shad Ali. Phytopathology  http://dx.doi.org/10.1094/PHYTO-01-15-0006-R Published online April 14, 2015

This paper is behind a paywall.

For anyone who recognized that wormwood is a constituent of Absinthe, a liquor that is banned in many parts of the world due to possible side effects associated with the wormwood, here’s more about it from the Wormwood overview page on WebMD (Note: Links have been removed),

Wormwood is an herb. The above-ground plant parts and oil are used for medicine.

Wormwood is used in some alcoholic beverages. Vermouth, for example, is a wine beverage flavored with extracts of wormwood. Absinthe is another well-known alcoholic beverage made with wormwood. It is an emerald-green alcoholic drink that is prepared from wormwood oil, often along with other dried herbs such as anise and fennel. Absinthe was popularized by famous artists and writers such as Toulouse-Lautrec, Degas, Manet, van Gogh, Picasso, Hemingway, and Oscar Wilde. It is now banned in many countries, including the U.S. But it is still allowed in European Union countries as long as the thujone content is less than 35 mg/kg. Thujone is a potentially poisonous chemical found in wormwood. Distilling wormwood in alcohol increases the thujone concentration.

Returning to the matter at hand, as I’ve noted previously elsewhere, research into the toxic effects associated with nanomaterials (e.g. silver nanoparticles) is a complex process.

Steep (1) at International Symposium on Electronic Arts (ISEA) 2015 in Vancouver, Canada

Our paper (Raewyn Turner, an artist from New Zealand,  and mine, Maryse de la Giroday), Steep (I): a digital poetry of gold nanoparticles, has been accepted for the 2015 International Symposium on Electronic Arts (ISEA) to be held in Vancouver, Canada from Aug. 14 – 18, 2015. I last wrote about ISEA 2015 in a Dec. 19, 2014 post where I indicated more information about our project would be forthcoming—the next week. Ah well, better late than never, eh?

Before getting to our project, here’s a little information on the symposium’s theme (from the Theme page),

ISEA2015’s theme of DISRUPTION invites a conversation about the aesthetics of change, renewal, and game-changing paradigms. We look to raw bursts of energy, reconciliation, error, and the destructive and creative forces of the new. Disruption contains both blue sky and black smoke. When we speak of radical emergence we must also address things left behind. Disruption is both incremental and monumental.

In practices ranging from hacking and detournement to inversions of place, time, and intention, creative work across disciplines constantly finds ways to rethink or reconsider form, function, context, body, network, and culture. Artists push, shape, break; designers reinvent and overturn; scientists challenge, disprove and re-state; technologists hack and subvert to rebuild.

Disruption and rupture are fundamental to digital aesthetics. Instantiations of the digital realm continue to proliferate in contemporary culture, allowing us to observe ever-broader consequences of these effects and the aesthetic, functional, social and political possibilities that arise from them.

Within this theme, we want to investigate trends in digital and internet aesthetics and revive exchange across disciplines. We hope to broaden the spheres in which disruptive aesthetics can be explored, crossing into the worlds of science, technology, design, visual art, contemporary and media art, innovation, performance, and sound.

At least two of the speakers are going to be very well aligned with the disruption theme (from the Keynote Speakers page),

TheYesMen Yes Men

Session Title: Tactical and Creative Resistance

The Yes Men, Andy Bichlbaum and Mike Bonanno, have been called “the Jonathan Swift of the Jackass generation” by author Naomi Klein. The Yes Men have impersonated World Trade Organization, Dow Chemical Corporation, and Bush administration spokesmen on TV and at business conferences around the world. They do this (a) in order to demonstrate some of the mechanisms that keep bad people and ideas in power, and (b) because it’s absurdly fun. As the Yes Men, they use humor, truth and lunacy to bring media attention to the crimes of their unwilling employers. Their second film, The Yes Men Fix the World, won the audience award at this year’s Berlin Film Festival, the Grierson Award for Most Entertaining Documentary, and went on to become a smash box-office sensation, only just barely surpassed by Avatar. Their main goal is to focus attention on the dangers of economic policies that place the rights of capital before the needs of people and the environment.

connorMichael Connor

Sessions Title: TBD

Michael Connor is the Editor and Curator of Rhizome at the New Museum. Connor’s work focuses on artists’ responses to cinema and new technologies. His past solo and collaborative projects as curator include: ‘Liquid Crystal Palace,’ Honor Fraser, Los Angeles; ‘Street Digital’ (works by artist duo JODI); ‘Wild Sky,’ Edith-Russ Haus, Oldenburg, Germany; ‘Screen Worlds’, ACMI in Melbourne; ‘Essential Cinema’ at the Toronto Film Festival, and ‘The New Normal’ touring exhibition. Connor previously worked as Curator at FACT, Liverpool and Head of Exhibitions at BFI Southbank, London.

Brian Massumi

Session Title: No One Without Another: Creativity and Decision in the Transindividual Fold

Brian Massumi is professor of communication at the University of Montreal. He specializes in the philosophy of experience, art and media theory, and political philosophy. His most recent books include Politics of Affect (Polity, 2015), The Power at the End of the Economy (Duke UP, 2015), and What Animals Teach Us about Politics (Duke UP, 2014). He is co-author with Erin Manning of Thought in the Act: Passages in the Ecology of Experience (co-written with Erin Manning; University of Minnesota Press, 2014). Also with Erin Manning and the SenseLab collective, he participates in the collective exploration of new ways of bringing philosophical and artistic practices into collaborative interaction, most recently in the frame of the “Immediations: Art, Media, Event” international partnership project.

DMoulon

Dominique Moulon

Sessions Title: TBD

Dominique Moulon studied visual art at the Fine Art School (ENSA) of Bourges and holds a Master’s Degree in aesthetics, science and technology from the University of Paris 8. Member of the Observatory of Digital Worlds in Humanities (OMNSH), of the International Association of Art Critics (AICA), of the Opline Prize for online contemporary art and founder of MediaArtDesign.net ; he also writes articles for Art Press, Digital MCD, The Seen and Neural. He is the Artistic Director of the media art fair Variation Paris and currently curator in residence at the art center of the Maison Populaire in Montreuil. Dominique Moulon teaches new media at Parsons (The New School for Design), ECV (Ecole de Communication Visuelle) and EPSAA (Ecole Professionnelle Supérieure d’Arts Graphiques) in Paris. He has also been a regular guest professor at the School of the Art Institute of Chicago (SAIC), the National School of Fine Arts (ENSBA) in Paris, The Fresnoy (Studio national des arts contemporains) and the University of Paris 8. His book Contemporary New Media Art was published in French by Nouvelles Editions Scala in 2011 and in English as an e-book in 2013. He is doing research at the laboratory Art & Flux (CNRS) of the University of Paris 1 Panthéon-Sorbonne while preparing his next book on the relationships between art, technology and society. As an expert in digital cultures, he has also been sollicited for his input by some companies like Axa, Accenture, Google, Landor or Renault.

Hildegard Westerkamp

Westerkamp_2012

Sessions Title: TBD

Hildegard Westerkamp has lectured on topics of listening, environmental sound and acoustic ecology and has conducted soundscape workshops internationally. By focusing the ears’ attention to details in the acoustic environment, her compositional work draws attention to the act of listening itself and to the inner, hidden spaces of the environment we inhabit. For details check her website: http://www.sfu.ca/~westerka

Her music has been commissioned by CBC Radio, Canada Pavilion at Expo ’86, Ars Electronica (Linz), Österreichischer Rundfunk, Zentrum für Kunst und Medien in Germany…. She received Honorable Mentions in competitions such as Prix Ars Electronica in Austria, Prix Italia, and the International Competition for Electroacoustic Music in Bourges, as well as a Recommendation for Broadcast from the International Music Council’s 4th International Rostrum of Electroacoustic Music. Her articles have been published in Radio Rethink, Kunstforum, Musicworks, MusikTexte and a variety of books… For an extensive exploration into her compositional work see Andra McCartney’s Sounding Places: Situated Conversations through the Soundscape Work of Hildegard Westerkamp, York University, Toronto, 1999, and in the internet at: http://beatrouteproductions.com/Andradiss.pdf

As part of Vancouver New Music’s yearly season she has coordinated and led  Soundwalks for some years since 2003, which in turn inspired the creation of The Vancouver Soundwalk Collective.

A founding member of the World Forum for Acoustic Ecology (WFAE, see: www.wfae.net), and long-time co-editor of its journal Soundscape, Westerkamp was a researcher for R. Murray Schafer’s World Soundscape Project in the Seventies, and has taught acoustic communication at Simon Fraser University with colleague Barry Truax.

Sara Diamond

Biography coming soon

As for the last speaker on the list, Sara Diamond is the president of the Ontario College of Art and Design University (OCAD University). Her professional focus is digital media and prior to heading OCAD University she was the Artistic Director of Media and Visual Art and Director of Research at the Banff Centre. You can find out more about Sara Diamond here.

Back to Steep, this is a project concerning gold nanoparticles. Here’s what Raewyn wrote about it on the homepage of the Steep website,

The general atmosphere is saturated and awash with particles and vibrations that are transpired by living beings and everything on earth. Emerging  into the troposphere, sounds and fragrances arise from cultural, social and political systems that have engineered the landscapes and thus mindscapes into settlements, habitations, fields, factories, front lawns and streets.

In the absence of a visceral sensing of the atmospheric ocean of particles and cues which are in dynamic flux with perception., Steep combines art+ science+ technology to explore sensing gold nanotechnology, where it accumulates, changes over time, and how it may affect living beings and the environment

Raewyn, a visual artist (video, painting, sculpture, interactive installations) and concept and design theatre artist and lighting designer located in Auckland, New Zealand, contacted me, located in Vancouver, Canada, a few years ago after reading some of the material I have on gold nanoparticles. She wanted to make contact with a scientist who was examining gold nanoparticles as they circulate from products into the air, the water, and the soil. Eventually I remembered the Duke University mesocosm project, located in Durham, North Carolina, at the Center for the Environmental Implication of Nano Technology (CEINT) led by Mark Wiesner (first mentioned here in an Aug. 15, 2011 post) and so Raewyn found her scientist and, although she wasn’t looking for one, a writer too. Her longtime collaborator, Brian Harris (located in Auckland, New Zealand), has an electronics background and is an independent designer and inventor who “invents and creates large scale finely tuned adaptive mechatronics and bespoke equipment. His inventions for motion control, stabilising camera mounts for aerial photography and robotic trajectories have been used in local and international tv, commercial and film productions.” (from the Steep About Us page).

For our first Steep project, Raewyn and I are working on a digital poetry installation. Here’s more about the project from the paper,

Steep is an international art/science research project examining the impact gold and gold nanoparticles have had in the past and could have in the future. Designed as a multi-year, multidisciplinary project with a rotating cast of collaborators, Steep is based on the current state of scientific research and its flexibility as a project reflects the uncertain and disruptive state of nanoscience and nanotechnology (as they are sometimes referred to).

    Steep (I) a digital poetry of gold nanoparticles, our first piece, is largely concerned with the elements of air and earth or more fancifully, gold in all its forms: myth, metaphor, and reality as it transitions visibly and invisibly throughout our environment.

The following poetry excerpt and video sample accompanying this submission [the video sample is not included in this posting] are works in progress and a research project within themselves.

Yearning
(excerpt)

shards of sun
hidden in the river’s silted bed
buried beneath the earth’s skin

a beautiful killing
in the cold, cold river
in the darkness underground

opportunities made of gold
wealth beyond Croesus’ and Midas’ imaginings
shining brighter than the sun

The other two parts of the trilogy are titled: Light/Shadow and Discovery respectively. I may have to change that last three lines to:

opportunities of gold
beyond Midas’ and Croesus’ imaginings
brighter than the sun

Raewyn and I are quite excited but there’s still work to do (our reviewers had comments).

FrogHeart and 2014: acknowledging active colleagues and saying good-bye to defunct blogs and hello to the new

It’s been quite the year. In Feb. 2014, TED offered me free livestreaming of the event in Vancouver. In March/April 2014, Google tweaked its search function and sometime in September 2014 I decided to publish two pieces per day rather than three with the consequence that the visit numbers for this blog are lower than they might otherwise have been. More about statistics and traffic to this blog will be in the post I usually publish just the new year has started.

On other fronts, I taught two courses (Bioelectronics and Nanotechnology, the next big idea) this year for Simon Fraser University (Vancouver, Canada) in its Continuing Studies (aka Lifelong Learning) programmes. I also attended a World Congress on Alternatives to Animal Testing in the Life Sciences in Prague. The trip, sponsored by SEURAT-1 (Safety Evaluation Ultimately Replacing Animal Testing), will result in a total of five stories, the first having been recently (Dec. 26, 2014) published. I’m currently preparing a submission for the International Symposium on Electronic Arts being held in Vancouver in August 2015 based on a project I have embarked upon, ‘Steep’. Focused on gold nanoparticles, the project is Raewyn Turner‘s (an artist from New Zealand) brainchild. She has kindly opened up the project in such a way that I too can contribute. There are two other members of the Steep project, Brian Harris, an electrical designer, who works closely with Raewyn on a number of arts projects and there’s Mark Wiesner as our science consultant. Wiesner is a professor of civil and environmental engineering,at Duke University in North Carolina.

There is one other thing which you may have noticed, I placed a ‘Donate’ button on the blog early in 2014.

Acknowledgements, good-byes, and hellos

Dexter Johnson on his Nanoclast blog (on the IEEE [Institute of Electrical and Electronics Engineers] website) remains a constant in the nano sector of the blogosphere where he provides his incisive opinions and context for the nano scene.

David Bruggeman on his Pasco Phronesis blog offers valuable insight into the US science policy scene along with a lively calendar of art/science events and an accounting of the science and technology guests on late night US television.

Andrew Maynard archived his 2020 Science blog in July 2014 but he does continue writing and communication science as director of the University of Michigan Risk Science Center. Notably, Andrew continues to write, along with other contributors, on the Risk Without Borders blog at the University of Michigan.

Sadly, Cientifica, a emerging technologies business consultancy, where Tim Harper published a number of valuable white papers, reports, and blog postings is no longer with us. Happily, Tim continues with an eponymous website where he blogs and communicates about various business interests, “I’m currently involved in graphene, nanotechnology, construction, heating, and biosensing, working for a UK public company, as well as organisations ranging from MIT [Massachusetts Institute of Technology] to the World Economic Forum.” Glad to you’re back to blogging Tim. I missed your business savvy approach and occasional cheekiness!

I was delighted to learn of a new nano blog, NanoScéal, this year and relieved to see they’re hanging in. Their approach is curatorial where they present a week of selected nano stories. I don’t think a lot of people realize how much work a curatorial approach requires. Bravo!

Sir Martyn Poliakoff and the Periodic Table of Videos

Just as I was wondering what happened to the Periodic Table of Videos (my April 25, 2011 post offers a description of the project) Grrl Scientist on the Guardian science blog network offers information about one of the moving forces behind the project, Martyn Poliakoff in a Dec. 31, 2014 post,

This morning [Dec. 31, 2014], I was most pleased to learn that Martyn Poliakoff, professor of chemistry at the University of Nottingham, was awarded a bachelor knighthood by the Queen. So pleased was I that I struggled out of bed (badly wrecked back), my teeth gritted, so I could share this news with you.

Now Professor Poliakoff — who now is more properly known as Professor SIR Martyn Poliakoff — was awarded one of the highest civilian honours in the land, and his continued online presence has played a significant role in this.

“I think it may be the first time that YouTube has been mentioned when somebody has got a knighthood, and so I feel really quite proud about that. And I also really want to thank you YouTube viewers who have made this possible through your enthusiasm for chemistry.”

As for the Periodic Table of Videos, the series continues past the 118 elements currently identified to a include discussions on molecules.

Science Borealis, the Canadian science blog aggregator, which I helped to organize (albeit desultorily), celebrated its first full year of operation. Congratulations to all those who worked to make this project such a success that it welcomed its 100th blog earlier this year. From a Sept. 24, 2014 news item on Yahoo (Note: Links have been removed),

This week the Science Borealis team celebrated the addition of the 100th blog to its roster of Canadian science blog sites! As was recently noted in the Council of Canadian Academies report on Science Culture, science blogging in Canada is a rapidly growing means of science communication. Our digital milestone is one of many initiatives that are bringing to fruition the vision of a rich Canadian online science communication community.

The honour of being syndicated as the 100th blog goes to Spider Bytes, by Catherine Scott, an MSc [Master of Science] student at Simon Fraser University in Burnaby, British Columbia. …

As always, it’s been a pleasure and privilege writing and publishing this blog. Thank you all for your support whether it comes in the form of reading it, commenting, tweeting,  subscribing, and/or deciding to publish your own blog. May you have a wonderful and rewarding 2015!

Reducing animal testing for nanotoxicity—PETA (People for the Ethical Treatment of Animals) presentation at NanoTox 2014

Writing about nanotechnology can lead you in many different directions such as the news about PETA (People for the Ethical Treatment of Animals) and its poster presentation at the NanoTox 2014 conference being held in Antalya, Turkey from April 23 – 26, 2014. From the April 22, 2014 PETA news release on EurekAlert,

PETA International Science Consortium Ltd.’s nanotechnology expert will present a poster titled “A tiered-testing strategy for nanomaterial hazard assessment” at the 7th International Nanotoxicology Congress [NanoTox 2014] to be held April 23-26, 2014, in Antalya, Turkey.

Dr. Monita Sharma will outline a strategy consistent with the 2007 report from the US National Academy of Sciences, “Toxicity Testing in the 21st Century: A Vision and a Strategy,” which recommends use of non-animal methods involving human cells and cell lines for mechanistic pathway–based toxicity studies.

Based on the current literature, the proposed strategy includes thorough characterization of nanomaterials as manufactured, as intended for use, and as present in the final biological system; assessment using multiple in silico and in vitro model systems, including high-throughput screening (HTS) assays and 3D systems; and data sharing among researchers from government, academia, and industry through web-based tools, such as the Nanomaterial Registry and NanoHUB

Implementation of the proposed strategy will generate meaningful information on nanomaterial properties and their interaction with biological systems. It is cost-effective, reduces animal use, and can be applied for assessing risk and making intelligent regulatory decisions regarding the use and disposal of nanomaterials.

PETA’s International Science Consortium has recently launched a nanotechnology webpage which provides a good overview of the basics and, as one would expect from PETA, a discussion of relevant strategies that eliminate the use of animals in nanotoxicity assessment,

What is nano?

The concept of fabricating materials at an atomic scale was introduced in 1959 by physicist Richard Feynman in his talk entitled “There’s Plenty of Room at the Bottom.” The term “nano” originates from the Greek word for “dwarf,” which represents the very essence of nanomaterials. In the International System of Units, the prefix “nano” means one-billionth, or 10-9; therefore, one nanometer is one-billionth of a meter, which is smaller than the thickness of a sheet of paper or a strand of hair.  …

Are there different kinds of nano?

The possibility of controling biological processes using custom-synthesized materials at the nanoscale has intrigued researchers from different scientific fields. With the ever increasing sophistication of nanomaterial synthesis, there has been an exponential increase in the number and type of nanomaterials available or that can be custom synthesized. Table 1 lists some of the nanomaterials that are currently available.

….

Oddly, given the question ‘Are there different kinds of nano?’, there’s no mention of nanobots.  Still it’s understandable that they’d focus on nanomaterials which are, as far as I know, the only ‘nano’ anything tested for toxicity. On that note, PETA’s Nanotechnology page offers this revelatory listing (scroll down about 3/4 of the way),

The following are some of the web-based tools being used by nanotoxicologists and material scientists:

Getting back to the NanoTox conference being held now in Antalya, I noticed a couple of familiar names on the list of keynote speakers (scroll down about 15% of the way), Kostas Kostarelos (last mentioned in a Feb. 28, 2014 posting about scientific publishing and impact factors’ scroll down about 1/2 way) and Mark Wiesner (last mentioned in a Nov. 13, 2013 posting about a major grant for one of his projects).

Duke University’s (North Carolina, US) Center for Environmental Implications of NanoTechnology (CEINT) wins $15M grant

A Nov. 13, 2013 news item on Azonano announces that the Center for Environmental Implications of Nanotechnology (CEINT) at Duke University has been awarded $15M,

A pioneering, multi-institution research center headquartered at Duke’s Pratt School of Engineering has just won $15-million grant renewal from the National Science Foundation and the US Environmental Protection Agency to continue learning more about where nanoparticles accumulate, how they interact with other chemicals and how they affect the environment.

Founded in 2008, the Center for Environmental Implications of NanoTechnology (CEINT) has been evaluating the effect of long-term nanomaterial exposure on organisms and ecosystems.

“The previous focus has been on studying simple, uniform nanomaterials in simple environments,” said Mark Wiesner, James L. Meriam Professor of Civil & Environmental Engineering and director of CEINT. “As we look to the next five years, we envision a dramatically different landscape. We will be evaluating more complex nanomaterials in more realistic natural environments such as agricultural lands and water treatment systems where these materials are likely to be found.”

The Nov. 11, 2013 Duke University news release by Karyn Hede, which originated the news item, provides some history and context for CEINT (Note: Links have been removed),

When CEINT formed, little research had been done on how materials manufactured at the nanoscale—about 1/10,000th the diameter of a human hair—enter the environment and whether their size and unique properties render them a new category of environmental risk. For example, nanoparticles can be highly reactive with other chemicals in the environment and had been shown to disrupt activities in living organisms. Indeed, nanosilver is used in clothing precisely because it effectively kills odor-causing bacteria.

To tackle this expansive research agenda, CEINT leadership assembled a multi-institutional research team encompassing expertise in ecosystems biology, chemistry, geology, materials science, computational science, mathematical modeling and other specialties, to complement its engineering expertise. The Center has 29 faculty collaborators, as well as 76 graduate and undergraduate students participating in research. Over its first five years, CEINT has answered some of the most pressing questions about environmental risk and has learned where to focus future research.

The center also pioneered the use of a new test chamber, called a mesocosm, that replicates a small wetland environment. “Over the long term, we want to evaluate how nanoparticles bioaccumulate in complex food webs,” said Emily Bernhardt, an associate professor of biology at Duke and ecosystem ecologist who helped design the simulated ecosystems. “The additional funding will allow us to study the subtle effect of low-dose exposure on ecosystems over time, as well as complex interactions among nanoparticles and other environmental contaminants.”

Looking forward, the investigators at CEINT plan to expand the use of systems modeling and to create a “knowledge commons,” a place to store various kinds of data that can then be analyzed as a whole, said CEINT Executive Director Christine Hendren.

“Our investigators and collaborators are located across the globe,” Hendren added. “We are committed to disseminating information that can be translated into responsible regulatory frameworks and that will be available to compare with results of future research.”

Key findings from CEINT’s first five years include:

Naturally occurring nanomaterials far outnumber engineered particles. CEINT scientist Michael Hochella, a geoscientist at Virginia Tech, inventoried nanoparticles and concluded that natural nanoparticles are found everywhere, from dust in the atmosphere to sea spray to volcanoes. The environmental risks of these natural nanomaterials are difficult to separate from engineered nanomaterials.

Engineered nanoparticles change once they enter the environment. Gregory V. Lowry, deputy director of CEINT and professor at Carnegie Mellon University, Pittsburgh, along with colleagues from the University of Birmingham, U.K. and the University of South Carolina found that the relatively large surface area of nanoparticles makes them highly reactive once they enter the environment. These transformations will alter their movement and toxicity and must be considered when studying nanomaterials. Their review article on this topic was named the best feature article of 2012 by the journal Environmental Science and Technology.

Nanoparticles can be visualized, even in complex environmental samples. A research team led by CEINT investigators Jie Liu, associate professor of chemistry at Duke, and CEINT Director Mark Wiesner showed that more than a dozen types of engineered nanoparticles, including silver, gold, and titanium dioxide, along with carbon nanotubes, can be surveyed using a technique called hyperspectral imaging, which measures light scattering caused by different types of nanoparticles. The new technique, co-developed by postdoctoral researcher Appala Raju Badireddy, is sensitive enough to analyze nanoparticles found in water samples ranging from ultrapurified to wastewater. It will be used in future long-term studies of how nanoparticles move and accumulate in ecological systems.

It is possible to estimate current and future volume of engineered nanomaterials. Understanding the volume of nanomaterials being produced and released into the environment is a crucial factor in risk assessment. CEINT researchers led by Christine Hendren measured the upper- and lower-bound annual U.S. production of five classes of nanomaterials, totaling as much as a combined 40,000 metric tons annually as of 2011.

Silver nanoparticles caused environmental stress in a simulated wetland environment. CEINT has developed  “mesocosms,”  open-air terrarium-like structures that simulate wetland ecosystems that can be evaluated over time. Even low doses of silver nanoparticles used in many consumer products produced about a third less biomass in a mesocosm. The researchers will now  look at how nanomaterials are transferred between organisms in a mesocosm.

I have written about CEINT and its work, including the mesocosm, many times. My August 15, 2011 posting offers an introduction to the CEINT mesocosm.

Natural and engineered nanoparticles in an Orion magazine podcast & in a NanoBosc machinima piece

The Jan. 16, 2013 Orion magazine podcast discussion (more about that later) regarding safety and engineered and natural nanoparticles arose from an article (worth reading) by Heather Millar in the magazine’s January/February 2013 issue, Pandora’s Boxes.

For anyone familiar with the term ‘Pandora’s box’, Millar’s and the magazine’s bias is made clear immediately, nanoparticles are small and threatening. From the Pandora’s box Wikipedia essay,

Today, the phrase “to open Pandora’s box” means to perform an action that may seem small or innocuous, but that turns out to have severe and far-reaching consequences. [emphases mine]

Millar’s article is well written and offers some excellent explanations. For example, there’s this from Pandora’s Boxes,

So chemistry and physics work differently if you’re a nanoparticle. You’re not as small as an atom or a molecule, but you’re also not even as big as a cell, so you’re definitely not of the macro world either. You exist in an undiscovered country somewhere between the molecular and the macroscopic. Here, the laws of the very small (quantum mechanics) merge quirkily with the laws of the very large (classical physics). Some say nanomaterials bring a third dimension to chemistry’s periodic table, because at the nano scale, long-established rules and groupings don’t necessarily hold up.

Then, she has some dodgier material,

Yet size seems to be a double-edged sword in the nanoverse. Because nanoparticles are so small, they can slip past the body’s various barriers: skin, the blood-brain barrier, the lining of the gut and airways. Once inside, these tiny particles can bind to many things. They seem to build up over time, especially in the brain. Some cause inflammation and cell damage. Preliminary research shows this can harm the organs of lab animals, though the results of some of these studies are a matter of debate.

Some published research has shown that inhaled nanoparticles actually become more toxic as they get smaller. Nano–titanium dioxide, one of the most commonly used nanoparticles (Pop-Tarts, sunblock), has been shown to damage DNA in animals and prematurely corrode metals. Carbon nanotubes seem to penetrate lungs even more deeply than asbestos. [emphases mine]

I think it’s worth ‘unpacking’ these two paragraphs, so here goes.  Slipping past the body’s barriers is a lot more difficult than Millar suggests in the first paragraph. My July 4, 2012 posting on breakthough research  where they penetrated the skin barrier includes this comment from me,

After all the concerns  about nanosunscreens and nanoparticles penetrating the skin raised by civil society groups, the Friends of the Earth in particular, it’s interesting to note that doctors and scientists consider penetration of the skin barrier to be extremely difficult. Of course, they seem to have solved [as of July 2012] that problem which means the chorus of concerns may rise to new heights.

I had a followup in my Oct.3, 2012 posting titled, Can nanoparticles pass through the skin or not?, suggesting there’s still a lot of confusion about this topic even within the scientific community.

Moving on to the other ‘breaches’. As I recall, there was a recent  (Autumn 2012?) nanomedicine research announcement that the blood-brain barrier was breached by nanoparticles. I haven’t yet encountered any mention of breaching the gut and I mention lungs in my next paragraph where I discuss carbon nanotubes.

As for that second paragraph, it’s an example of scaremongering. ‘Inhaled nanoparticles become more toxic as their size decreases’—ok. Why mention nano-titanium oxide in pop tarts and sunblocks, which are not inhaled, in the followup sentence? As for the reference to DNA damage and corroded metals further on, this is straight out of the Friends of the Earth literature which often cites research in a misleading fashion including those two pieces.  There is research supporting part of Millar’s statement about carbon nanotubes—provided they are long and multiwalled. In fact, as they get shorter, the resemblance to asbestos fibers in the lungs or elsewhere seems to disappear as per my Aug 22, 2012 posting and my Jan. 16, 2013 posting.

You don’t need to read the article before listening to the fascinating Jan. 16, 2013 Orion magazine podcast with Millar (reading portions of her article) and expert guests, Mark Wiesner from Duke University and director of their Center for Environmental Implications of Nano Technology (CEINT was first mentioned in my April 15, 2011 posting), Ronald Sandler from Northeastern University and author of Nanotechnology: The Social And Ethical Issues, and Jaydee Hanson, policy director for the International Center for Technology Assessment.

The discussion between Wiesner, Sandler, and Hanson about engineered and natural nanoparticles is why I’ve called the podcast fascinating. Hearing these experts ‘fence’ with each other highlights the complexities and subtleties inherent in discussions about emerging technologies (nano or other) and risk. Millar did not participate in that aspect of the conversation and I imagine that’s due to the fact that she has only been researching this area for six months while the other speakers all have several years worth experience individually and, I suspect, may have debated each other previously.

At the risk of enthusing too much about naturally occurring nanoparticles, I’m mentioning, again (my Feb. 1, 2013 posting), the recently published book by Nanowiki, Nanoparticles Before Nanotechnology, in the context of the stunning visual images used to illustrate the book. I commented previously about them and Victor Puntes of the Inorganic Nanoparticles Group at the Catalan Institute of Nanotechnology (ICN) and one of the creators of this imagery, kindly directed me to a machinima piece (derived from the NanoBosc Second Life community) which is the source for the imagery. Here it is,

NanoBosc from Per4mance MetaLES ..O.. on Vimeo.

Happy Weekend!