Category Archives: health and safety

Singing posters and talking shirts can communicate with you via car radio or smartphones

Singing posters and talking shirts haven’t gone beyond the prototype stage yet but I imagine University of Washington engineers are hoping this will happen sooner rather than later. In the meantime, they are  presenting their work at a conference according to a March 1, 2017 news item on ScienceDaily,

Imagine you’re waiting in your car and a poster for a concert from a local band catches your eye. What if you could just tune your car to a radio station and actually listen to that band’s music? Or perhaps you see the poster on the side of a bus stop. What if it could send your smartphone a link for discounted tickets or give you directions to the venue?

Going further, imagine you go for a run, and your shirt can sense your perspiration and send data on your vital signs directly to your phone.

A new technique pioneered by University of Washington engineers makes these “smart” posters and clothing a reality by allowing them to communicate directly with your car’s radio or your smartphone. For instance, bus stop billboards could send digital content about local attractions. A street sign could broadcast the name of an intersection or notice that it is safe to cross a street, improving accessibility for the disabled. In addition, clothing with integrated sensors could monitor vital signs and send them to a phone. [emphasis mine]

“What we want to do is enable smart cities and fabrics where everyday objects in outdoor environments — whether it’s posters or street signs or even the shirt you’re wearing — can ‘talk’ to you by sending information to your phone or car,” said lead faculty and UW assistant professor of computer science and engineering Shyam Gollakota.

“The challenge is that radio technologies like WiFi, Bluetooth and conventional FM radios would last less than half a day with a coin cell battery when transmitting,” said co-author and UW electrical engineering doctoral student Vikram Iyer. “So we developed a new way of communication where we send information by reflecting ambient FM radio signals that are already in the air, which consumes close to zero power.”

The UW team has — for the first time — demonstrated how to apply a technique called “backscattering” to outdoor FM radio signals. The new system transmits messages by reflecting and encoding audio and data in these signals that are ubiquitous in urban environments, without affecting the original radio transmissions. Results are published in a paper to be presented in Boston at the 14th USENIX Symposium on Networked Systems Design and Implementation in March [2017].

The team demonstrated that a “singing poster” for the band Simply Three placed at a bus stop could transmit a snippet of the band’s music, as well as an advertisement for the band, to a smartphone at a distance of 12 feet or to a car over 60 feet away. They overlaid the audio and data on top of ambient news signals from a local NPR radio station.

The University of Washington has produced a video demonstration of the technology

A March 1, 2017 University of Washington news release (also on EurekAlert), which originated the news item, explains further (Note: Links have been removed),

“FM radio signals are everywhere. You can listen to music or news in your car and it’s a common way for us to get our information,” said co-author and UW computer science and engineering doctoral student Anran Wang. “So what we do is basically make each of these everyday objects into a mini FM radio station at almost zero power.”

Such ubiquitous low-power connectivity can also enable smart fabric applications such as clothing integrated with sensors to monitor a runner’s gait and vital signs that transmits the information directly to a user’s phone. In a second demonstration, the researchers from the UW Networks & Mobile Systems Lab used conductive thread to sew an antenna into a cotton T-shirt, which was able to use ambient radio signals to transmit data to a smartphone at rates up to 3.2 kilobits per second.

The system works by taking an everyday FM radio signal broadcast from an urban radio tower. The “smart” poster or T-shirt uses a low-power reflector to manipulate the signal in a way that encodes the desired audio or data on top of the FM broadcast to send a “message” to the smartphone receiver on an unoccupied frequency in the FM radio band.

“Our system doesn’t disturb existing FM radio frequencies,” said co-author Joshua Smith, UW associate professor of computer science and engineering and of electrical engineering. “We send our messages on an adjacent band that no one is using — so we can piggyback on your favorite news or music channel without disturbing the original transmission.”

The team demonstrated three different methods for sending audio signals and data using FM backscatter: one simply overlays the new information on top of the existing signals, another takes advantage of unused portions of a stereo FM broadcast, and the third uses cooperation between two smartphones to decode the message.

“Because of the unique structure of FM radio signals, multiplying the original signal with the backscattered signal actually produces an additive frequency change,” said co-author Vamsi Talla, a UW postdoctoral researcher in computer science and engineering. “These frequency changes can be decoded as audio on the normal FM receivers built into cars and smartphones.”

In the team’s demonstrations, the total power consumption of the backscatter system was 11 microwatts, which could be easily supplied by a tiny coin-cell battery for a couple of years, or powered using tiny solar cells.

I cannot help but notice the interest in using this technology is for monitoring purposes, which could be benign or otherwise.

For anyone curious about the 14th USENIX Symposium on Networked Systems Design and Implementation being held March 27 – 29, 2017 in Boston, Massachusetts, you can find out more here.

Findings on oral exposure to nanoscale titanium dioxide

It’s been a while since I’ve run a piece on health concerns and nanoparticles. The nanoparticles in question are titanium dioxide and the concerns centre on oral exposure to them according to a Jan. 24, 2017 news item on Nanowerk,

Researchers from INRA [French National Institute for Agricultural Research] and their partners have studied the effects of oral exposure to titanium dioxide, an additive (E171) commonly used in foodstuffs, especially confectionary. They have shown for the first time that E171 crosses the intestinal barrier in animals and reaches other parts of the body.

Immune system disorders linked to the absorption of the nanoscale fraction of E171 particles were observed. The researchers also showed that chronic oral exposure to the additive spontaneously induced preneoplastic lesions in the colon, a non-malignant stage of carcinogenesis, in 40% of exposed animals.

Moreover, E171 was found to accelerate the development of lesions previously induced for experimental purposes. While the findings show that the additive plays a role in initiating and promoting the early stages of colorectal carcinogenesis, they cannot be extrapolated to humans or more advanced stages of the disease. [emphasis mine]

A Jan. 20, 2017 IINRA press release, which originated the news item,  provides more detail about European use of titanium dioxide as a food additive and about the research,

Present in many products including cosmetics, sunscreens, paint and building materials, titanium dioxide (or TiO2), known as E171 in Europe, is also widely used as an additive in the food industry to whiten or give opacity to products. It is commonly found in sweets, chocolate products, biscuits, chewing gum and food supplements, as well as in toothpaste and pharmaceutical products. Composed of micro- and nanoparticles, E171 is nevertheless not labelled a “nanomaterial”, since it does not contain more than 50% of nanoparticles (in general it contains from 10-40%). The International Agency for Research on Cancer (IARC) evaluated the risk of exposure to titanium dioxide by inhalation (occupational exposure), resulting in a Group 2B classification, reserved for potential carcinogens for humans.

Today, oral exposure to E171 is a concern, especially in children who tend to eat a lot of sweets. INRA researchers studied the product as a whole (that is, its mixed composition of micro- and nanoparticules), and have also evaluated the effect of the nanoscale particle fraction alone, by comparing it to a model nanoparticle.

Titanium dioxide crosses the intestinal barrier and passes into the bloodstream

The researchers exposed rats orally to a dose of 10mg of E171 per kilogram of body weight per day, similar to the exposure humans experience through food consumption (data from European Food Safety Agency, September 20162). They showed for the first time in vivo that titanium dioxide is absorbed by the intestine and passes into the bloodstream. Indeed, the researchers found titanium dioxide particles in the animals’ livers.

Titanium dioxide alters intestinal and systemic immune response

Titanium dioxide nanoparticles were present in the lining of the small intestine and in the colon, and entered the nuclei of the immune cells of Peyer’s patches, which induce immune response in the intestine. The researchers showed an imbalance in immune response, ranging from a defect in the production of cytokines in Peyer’s patches to the development of micro-inflammation in colon mucosa. In the spleen, representative of systemic immunity, exposure to E171 increases the capacity of immune cells to produce pro-inflammatory cytokines when they are activated in vitro.

Chronic oral exposure to titanium dioxide plays a role in initiating and promoting early stages of colorectal carcinogenesis

The researchers exposed rats to regular oral doses of titanium dioxide through drinking water for 100 days. In a group of rats previously treated with an experimental carcinogen, exposure to TiO2 led to an increase in the size of preneoplastic lesions. In a group of healthy rats exposed to E171, four out of eleven spontaneously developed preneoplastic lesions in the intestinal epithelium. Non-exposed animals presented no anomalies at the end of the 100-day study. These results indicate that E171 both initiates and promotes the early stages of colorectal carcinogenesis in animals.

These studies show for the first time that the additive E171 is a source of titanium dioxide nanoparticles in the intestine and the entire body, with consequences for both immune function and the development of preneoplastic lesions in the colon. These first findings justify a carcinogenesis study carried out under OECD [Organization for Economic Cooperation and Development] guidelines to continue observations at a later stage of cancer. They provide new data for evaluating the risks of the E171 additive in humans.

These studies were carried out within the framework of the Nanogut project, financed by the French Agency for Food, Environmental and Occupational Health & Safety (ANSES) within the French national programme for research related to the environment, health and the workplace (PNR EST) and coordinated by INRA. Sarah Bettini’s university thesis contract was financed by the French laboratory of excellence LabEx SERENADE.

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

Food-grade TiO2 impairs intestinal and systemic immune homeostasis, initiates preneoplastic lesions and promotes aberrant crypt development in the rat colon by Sarah Bettini, Elisa Boutet-Robinet, Christel Cartier, Christine Coméra, Eric Gaultier, Jacques Dupuy, Nathalie Naud, Sylviane Taché, Patrick Grysan, Solenn Reguer, Nathalie Thieriet, Matthieu Réfrégiers, Dominique Thiaudière, Jean-Pierre Cravedi, Marie Carrière, Jean-Nicolas Audinot, Fabrice H. Pierre, Laurence Guzylack-Piriou, & Eric Houdeau. Scientific Reports 7, Article number: 40373 (2017) doi:10.1038/srep40373 Published online: 20 January 2017

This paper is open access.

The research is concerning but they don’t want to draw any conclusions yet, which explains the recommendation for further research.

Using sugar for a better way to clean nanoparticles from organisms

Researchers at the US National Institute of Standards and Technology (NIST) have found that a laboratory technique used for over 60 years is the best way to date to clean nanoparticles from organisms. From a Jan. 26, 2017 news item on ScienceDaily,

Sometimes old-school methods provide the best ways of studying cutting-edge tech and its effects on the modern world.

Giving a 65-year-old laboratory technique a new role, researchers at the National Institute of Standards and Technology (NIST) have performed the cleanest separation to date of synthetic nanoparticles from a living organism. The new NIST method is expected to significantly improve experiments looking at the potential environmental and health impacts of these manufactured entities. It will allow scientists to more accurately count how many nanoparticles have actually been ingested by organisms exposed to them.

A Jan. 26, 2017 NIST news release (also on EurekAlert), which originated the news item, offers more detail,

The common roundworm Caenorhabditis elegans has been used in recent years as a living model for laboratory studies of how biological and chemical compounds may affect multicellular organisms. These compounds include engineered nanoparticles (ENPs), bits of material between 1 and 100 nanometers (billionths of a meter, or about 1/10,000 the diameter of a red blood cell). Previous research has often focused on quantifying the amount and size of engineered nanoparticles ingested by C. elegans. Measuring the nanoparticles that actually make it into an organism is considered a more relevant indicator of potential toxicity than just the amount of ENPs to which the worms are exposed.

Traditional methods for counting ingested ENPs have produced questionable results. Currently, researchers expose C. elegans to metal ENPs such as silver or gold in solution, then rinse the excess particles away with water followed by centrifugation and freeze-drying. A portion of the “cleaned” sample produced is then typically examined by a technique that determines the amount of metal present, known as inductively coupled plasma mass spectrometry (ICP-MS). It often yields ENP counts in the tens of thousands per worm; however, those numbers always seem too high to NIST researchers working with C. elegans.

“Since ICP-MS will detect all of the nanoparticles associated with the worms, both those ingested and those that remain attached externally, we suspect that the latter is what makes the ‘ENPs’ per-worm counts so high,” said NIST analytical chemist Monique Johnson (link sends e-mail), the lead author on the ACS Nano paper. “Since we only wanted to quantify the ingested ENPs, a more robust and reliable separation method was needed.”

Luckily, the solution to the problem was already in the lab.

Cross section of the roundworm C. elegans

Scanning electron micrograph showing a cross section of the roundworm C. elegans with two ingested engineered nanoparticles (red dots just right of center). Images such as this provided NIST researchers with visual confirmation that nanoparticle consumption actually occurred. Credit: K. Scott/NIST

In the course of culturing C. elegans for ENP-exposure experiments, Johnson and her colleagues had used sucrose density gradient centrifugation, a decades-old and established system for cleanly separating cellular components, to isolate the worms from debris and bacteria. “We wondered if the same process would allow us to perform an organism-from-ENP separation as well, so I designed a study to find out,” Johnson said.

In their experiment, the NIST researchers first exposed separate samples of C. elegans to low and high concentrations of two sizes of gold nanospheres, 30 and 60 nanometers in diameter. The researchers put each of the samples into a centrifuge and removed the supernatant (liquid portion), leaving the worms and ENPs in the remaining pellets. These were centrifuged twice in a salt solution (rather than just water as in previous separation methods), and then centrifuged again, but this time, through a uniquely designed sucrose density gradient.

“From top to bottom, our gradient consisted of a salt solution layer to trap excess ENPs and three increasingly dense layers of sucrose [20, 40 and 50 percent] to isolate the C. elegans,” Johnson explained. “We followed up the gradient with three water rinses and with centrifugations to ensure that only worms with ingested ENPs, and not the sucrose separation medium with any excess ENPs, would make it into the final pellet.”

Analyzing the range of masses in the ultrapurified samples indicated gold levels more in line with what the researchers expected would be found as ingested ENPs. Experimental validation of the NIST separation method’s success came when the worms were examined in detail under a scanning electron microscope (SEM).

“For me, the eureka moment was when I first saw gold ENPs in the cross section images taken from the C. elegans samples that had been processed through the sucrose density gradient,” Johnson said. “I had been dreaming about finding ENPs in the worm’s digestive tract and now they were really there!”

The high-resolution SEM images also provided visual evidence that only ingested ENPs were counted. “No ENPs were attached to the cuticle, the exoskeleton of C. elegans, in any of the sucrose density gradient samples,” Johnson said. “When we examined worms from our control experiments [processed using the traditional no-gradient, water-rinse-only separation method], there were a number of nanospheres found attached to the cuticle.

Now that it has been successfully demonstrated, the NIST researchers plan to refine and further validate their system for evaluating the uptake of ENPs by C. elegans. “Hopefully, our method will become a useful and valuable tool for reducing the measurement variability and sampling bias that can plague environmental nanotoxicology studies,” Johnson said.

They’ve tested this technique on gold nanoparticles, which begs the question, What kinds of nanoparticles can this technique be used for? Metal nanoparticles only or all nanoparticles?

I’m sure the researchers have already asked these questions and started researching the answers. While the rest of us wait, here’s a link to and a citation for the paper about this promising new technique,

Separation, Sizing, and Quantitation of Engineered Nanoparticles in an Organism Model Using Inductively Coupled Plasma Mass Spectrometry and Image Analysis by Monique E. Johnson, Shannon K. Hanna, Antonio R. Montoro Bustos, Christopher M. Sims, Lindsay C. C. Elliott, Akshay Lingayat, Adrian C. Johnston, Babak Nikoobakht, John T. Elliott, R. David Holbrook, Keana C. K. Scott, Karen E. Murphy, Elijah J. Petersen, Lee L. Yu, and Bryant C. Nelson. ACS Nano, 2017, 11 (1), pp 526–540 DOI: 10.1021/acsnano.6b06582 Publication Date (Web): December 16, 2016

Copyright This article not subject to U.S. Copyright. Published 2016 by the American Chemical Society

This paper is behind a paywall.

Nanoparticles can activate viruses lying dormant in lung cells

The nanoparticles in question are from combustion engines, which means that we are exposed to them. One other note, the testing has not been done on humans but rather on cells. From a Jan. 16, 2017 news item on ScienceDaily,

Nanoparticles from combustion engines can activate viruses that are dormant in in lung tissue cells. This is the result of a study by researchers of Helmholtz Zentrum München, a partner in the German Center for Lung Research (DZL), which has now been published in the journal Particle and Fibre Toxicology.

To evade the immune system, some viruses hide in cells of their host and persist there. In medical terminology, this state is referred to as a latent infection. If the immune system becomes weakened or if certain conditions change, the viruses become active again, begin to proliferate and destroy the host cell. A team of scientists led by Dr. Tobias Stöger of the Institute of Lung Biology and Prof. Dr. Heiko Adler, deputy head of the research unit Lung Repair and Regeneration at Helmholtz Zentrum München, now report that nanoparticles can also trigger this process.

A Jan. 16, 2017 Helmholtz Zentrum München press release (also on EurekAlert), which originated the news item, provides more detail,

“From previous model studies we already knew that the inhalation of nanoparticles has an inflammatory effect and alters the immune system,” said study leader Stöger. Together with his colleagues Heiko Adler and Prof. Dr. Philippe Schmitt-Kopplin, he showed that “an exposure to nanoparticles can reactivate latent herpes viruses in the lung.”

Specifically, the scientists tested the influence of nanoparticles typically generated by fossil fuel combustion in an experimental model for a particular herpes virus infection. They detected a significant increase in viral proteins, which are only produced with active virus proliferation. “Metabolic and gene expression analyses also revealed patterns resembling acute infection,” said Philippe Schmitt-Kopplin, head of the research unit Analytical BioGeoChemistry (BGC). Moreover, further experiments with human cells demonstrated that Epstein-Barr viruses are also ‘awakened’ when they come into contact with the nanoparticles.

Potential approach for chronic lung diseases

In further studies, the research team would like to test whether the results can also be transferred to humans. “Many people carry herpes viruses, and patients with idiopathic pulmonary fibrosis are particularly affected,” said Heiko Adler. “If the results are confirmed in humans, it would be important to investigate the molecular process of the reactivation of latent herpes viruses induced by particle inhalation. Then we could try to influence this pathway therapeutically.”

Special cell culture models shall therefore elucidate the exact mechanism of virus reactivation by nanoparticles. “In addition,” Stöger said, ”in long-term studies we would like to investigate to what extent  repeated nanoparticle exposure with corresponding virus reactivation leads to chronic inflammatory and remodeling processes in the lung.”

Further Information

Background:
In 2015 another group at the Helmholtz Zentrum München demonstrated how the Epstein-Barr virus  hides in human cells. In March 2016 researchers also showed that microRNAs silence immune alarm signals of cells infected with the Epstein-Barr virus.

Original Publication:
Sattler, C. et al. (2016): Nanoparticle exposure reactivates latent herpesvirus and restores a signature of acute infection. Particle and Fibre Toxicology, DOI 10.1186/s12989-016-0181-1

Here’s a link to and a citation for the paper on investigating latent herpes virus,

Nanoparticle exposure reactivates latent herpesvirus and restores a signature of acute infection by Christine Sattler, Franco Moritz, Shanze Chen, Beatrix Steer, David Kutschke, Martin Irmler, Johannes Beckers, Oliver Eickelberg, Philippe Schmitt-Kopplin, Heiko Adler. Particle and Fibre Toxicology201714:2 DOI: 10.1186/s12989-016-0181-1 Published: 10 January 2017

©  The Author(s). 2017

This paper is open access and, so too, is the 2016 paper.

XSEDE: the most advanced, powerful integrated digital resources in the world and nanomaterials

The University of Iowa does not jump to mind when considering powerhouse nanomaterial research; it seems that’s a mistake. An Oct. 19, 2016 news item on Nanowerk sets the record straight,

Chemists at the University of Iowa will research the effects of nanomaterials on the environment and human health using a network of supercomputers funded by the U.S. National Science Foundation.

Sara E. Mason, assistant professor in the Department of Chemistry, won an NSF award that grants her team access to the Extreme Science and Engineering Discovery Environment (XSEDE). The XSEDE project links computers, data, and people from around the world to establish a single, virtual system that scientists can interactively use to conduct research. It was started in 2011 and was renewed by the NSF last August.

The NSF says it “will be the most advanced, powerful, and robust collection of integrated advanced digital resources and services in the world.”

An Oct. 12, 2016 University of Iowa (UI) news release by Richard C. Lewis, which originated the news item, provides a little more detail,

The UI grant, valued at $72,503, essentially gives Mason’s team time on the supercomputer network, which they can access from their desktops. The researchers will use that time to study nanoparticles—matter far too small to be seen by the naked eye and present in a range of products, from sunscreen to advanced batteries for hybrid and electric vehicles.

The team hopes to better define the atom-to-atom interactions of various nanoparticles. Mason says the grant will “super charge” her computational research.

“To me, having four concurrent NSF research grants is a big deal, and now, having the boost of the computer time allows us to do even more,” Mason says. “XSEDE allows us to run simulations using quantum mechanics and highly parallelized computers. The outcome is new chemical insight into natural or widely used nanoparticles. We can then connect the chemistry to broader issues, such as human health and the behavior of nanomaterials in the environment.”

Mason’s group aims to find and design nanomaterials that are more benign to the environment and human health. Part of the search means trying out new elements in computational designs to find out how they interact, as well as their side effects, good or bad.

The XSEDE computers will give them far more computing horsepower to carry out those computational experiments.

“We can collectively get a lot more done in a shorter period of time,” says Joseph Bennett, co-principal investigator on the grant and a post-doctoral researcher in Mason’s group.

The UI is one of 15 institutions affiliated with the NSF-funded Center for Sustainable Nanotechnology, devoted to investigating the fundamental molecular mechanisms by which nanoparticles interact with biological systems.

I wish them good luck.

Mimicking rain and sun to test plastic for nanoparticle release

One of Canada’s nanotechnology experts once informed a House of Commons Committee on Health that nanoparticles encased in plastic (he was talking about cell phones) weren’t likely to harm you except in two circumstances (when workers were using them in the manufacturing process and when the product was being disposed of). Apparently, under some circumstances, that isn’t true any more. From a Sept. 30, 2016 news item on Nanowerk,

If the 1967 film “The Graduate” were remade today, Mr. McGuire’s famous advice to young Benjamin Braddock would probably be updated to “Plastics … with nanoparticles.” These days, the mechanical, electrical and durability properties of polymers—the class of materials that includes plastics—are often enhanced by adding miniature particles (smaller than 100 nanometers or billionths of a meter) made of elements such as silicon or silver. But could those nanoparticles be released into the environment after the polymers are exposed to years of sun and water—and if so, what might be the health and ecological consequences?

A Sept. 30, 2016 US National Institute of Standards and Technology (NIST) news release, which originated the news item, describes how the research was conducted and its results (Note: Links have been removed),

In a recently published paper (link is external), researchers from the National Institute of Standards and Technology (NIST) describe how they subjected a commercial nanoparticle-infused coating to NIST-developed methods for accelerating the effects of weathering from ultraviolet (UV) radiation and simulated washings of rainwater. Their results indicate that humidity and exposure time are contributing factors for nanoparticle release, findings that may be useful in designing future studies to determine potential impacts.

In their recent experiment, the researchers exposed multiple samples of a commercially available polyurethane coating containing silicon dioxide nanoparticles to intense UV radiation for 100 days inside the NIST SPHERE (Simulated Photodegradation via High-Energy Radiant Exposure), a hollow, 2-meter (7-foot) diameter black aluminum chamber lined with highly UV reflective material that bears a casual resemblance to the Death Star in the film “Star Wars.” For this study, one day in the SPHERE was equivalent to 10 to 15 days outdoors. All samples were weathered at a constant temperature of 50 degrees Celsius (122 degrees Fahrenheit) with one group done in extremely dry conditions (approximately 0 percent humidity) and the other in humid conditions (75 percent humidity).

To determine if any nanoparticles were released from the polymer coating during UV exposure, the researchers used a technique they created and dubbed “NIST simulated rain.” Filtered water was converted into tiny droplets, sprayed under pressure onto the individual samples, and then the runoff—with any loose nanoparticles—was collected in a bottle. This procedure was conducted at the beginning of the UV exposure, at every two weeks during the weathering run and at the end. All of the runoff fluids were then analyzed by NIST chemists for the presence of silicon and in what amounts. Additionally, the weathered coatings were examined with atomic force microscopy (AFM) and scanning electron microscopy (SEM) to reveal surface changes resulting from UV exposure.

Both sets of coating samples—those weathered in very low humidity and the others in very humid conditions—degraded but released only small amounts of nanoparticles. The researchers found that more silicon was recovered from the samples weathered in humid conditions and that nanoparticle release increased as the UV exposure time increased. Microscopic examination showed that deformations in the coating surface became more numerous with longer exposure time, and that nanoparticles left behind after the coating degraded often bound together in clusters.

“These data, and the data from future experiments of this type, are valuable for developing computer models to predict the long-term release of nanoparticles from commercial coatings used outdoors, and in turn, help manufacturers, regulatory officials and others assess any health and environmental impacts from them,” said NIST research chemist Deborah Jacobs, lead author on the study published in the Journal of Coatings Technology and Research (link is external).

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

Surface degradation and nanoparticle release of a commercial nanosilica/polyurethane coating under UV exposure by Deborah S. Jacobs, Sin-Ru Huang, Yu-Lun Cheng, Savelas A. Rabb, Justin M. Gorham, Peter J. Krommenhoek, Lee L. Yu, Tinh Nguyen, Lipiin Sung. J Coat Technol Res (2016) 13: 735. doi:10.1007/s11998-016-9796-2 First published online 13 July 2016

This paper is behind a paywall.

For anyone interested in the details about the House of Commons nano story I told at the start of this post, here’s the June 23, 2010 posting where I summarized the hearing on nanotechnology. If you scroll down about 50% of the way, you’ll find Dr. Nils Petersen’s (then director of Canada’s National Institute of Nanotechnology) comments about nanoparticles being encased. The topic had been nanosunscreens and he was describing the conditions under which he believed nanoparticles could be dangerous.

Germany has released a review of their research strategy for nanomaterials

A Sept. 24, 2016 posting by Lynn L. Bergeson and Carla N. Hutton on The National Law Review blog features a new report from German authorities (Note: A link has been removed),

On September 19, 2016, the Federal Institute for Occupational Safety and Health (BAuA) published a report entitled Review of the joint research strategy of the higher federal authorities — Nanomaterials and other advanced materials:  Application safety and environmental compatibility.  The report states that in a long-term research strategy, the higher federal authorities responsible for human and environmental safety — the German Environment Agency (UBA), the Federal Institute for Risk Assessment (BfR), BAuA, the Federal Institute for Materials Research and Testing (BAM), and the National Metrology Institute (PTB) — are accompanying the rapid pace of development of new materials from the points of view of occupational safety and health, consumer protection, and environmental protection.

Here’s a link to Review of the joint research strategy of the higher federal authorities — Nanomaterials and other advanced materials:  Application safety and environmental compatibility (PDF) and excerpts from the foreword (Note: There are some differences in formatting between what you see here and what you’ll see in the report),

The research strategy builds on the outcomes so far of the joint research strategy of the higher federal authorities launched in 2008 and first evaluated in 2013, “Nanotechnology: Health and Environmental Risks of Nanomaterials”1, while additionally covering other advanced materials where these pose similar risks to humans and the environment or where such risks need to be studied. It also takes up the idea of application safety of chemical products 2 from the New Quality of Work (INQA) initiative of the Federal Ministry of Labour and Social Affairs (BMAS) and the concept of sustainable
chemistry 3 endorsed by the Federal  Ministry  for  the  Environment, Nature Conservation, Building  and Nuclear Safety (BMUB). Application safety and environmental compatibility are aimed for advanced materials and derived products in order to largely rule out unacceptable risks to humans and the environment. This can be achieved by:

Using safe materials without hazardous properties for humans and the environment (direct application safety); or

Product design for low emissions and environmental compatibility over the entire product lifecycle (integrated application safety); or

Product stewardship, where producers support users in taking technical, organizational, and personal safety measures for the safe use and disposal of products (supported application safety).

As a comprising part of the Federal Government’s Nanotechnology Action Plan 2020, the update of the joint research strategy aims to contribute to governmental research in the following main areas:

 characterising and assessing the human and environmental risks of advanced materials
 Supporting research institutions and business enterprises
 Science-based revision of legal requirements and recommendations
 Public acceptance

The research strategy is to be implemented in projects and other research-related activities. These  include  governmental  research,  tendering  and  extramural  research  funding, and participation in mostly publicly supported projects with third-party funding. Additional activities will take place as part of policy advice and the ongoing work of the sovereign tasks of agencies involved. Interdisciplinary and transdisciplinary approaches will be used to better connect risk and safety research with innovation research and material development. In keeping up with the rapid pace of development, the time horizon for the research strategy is up to 2020. The research objectives address the research approaches likely to be actionable in this period. The research strategy will be supported by a working group and be evaluated and revised by the end of the Nanotechnology Action Plan 2020. tegy will be implemented in projects and other research-related activities, including governmental research, tendering and extramural research funding, and participation in mostly publicly supported projects with third-party funding.  Agencies will use interdisciplinary and transdisciplinary approaches to connect better risk and safety research with innovation research and material development. To keep up with the pace of development, the time horizon for the research strategy extends to 2020.  The research objectives in the report address the research approaches likely to be actionable in this period.  The research strategy will be supported by a working group and be evaluated and revised by the end of the Nanotechnology Action Plan 2020.

It’s always interesting to find out what’s happening elsewhere.

Walgreens (US-based pharmacy), As You Sow (civil society), and engineered hydroxyapatite (HA) nanoparticles

As You Sow has graced this blog before, notably in a March 13, 2015 posting about their success getting the corporate giant, Dunkin’ Donuts, to stop its practice of making powdered sugar whiter by adding nanoscale (and other scales) of titanium dioxide. What’s notable about As You Sow is that it files shareholder resolutions (in other words, the society owns shares of their corporate target) as one of its protest tactics.

This time, As You Sow has focused on Walgreens, a US pharmacy giant. This company has chosen a response that differs from Dunkin’ Donuts’ according to a Sept. 21, 2016 news item on Nanotechnology Now,

Rather than respond to shareholder concerns that Walgreens’ store-brand infant formula may contain harmful, “needle-like” nanomaterials, Walgreens filed a motion with the SEC [US Securities and Regulatory Commission] to block the inquiry.

A Sept. 21, 2016 As You Sow press release, which originated the news item, fills in a few details,

Walgreen’s Well Beginnings™ Advantage® infant formula has been reported to contain engineered hydroxyapatite (HA) nanoparticles, according to independent laboratory testing commissioned by nonprofit group Friends of the Earth. The E.U. Scientific Committee on Consumer Safety (SCCS) has determined that nano-HA may be toxic to humans and that the needle-form of nano-HA should not be used in products.

Walgreens’ “no-action letter” to the SEC argues that the company can exclude the shareholder proposal because “the use of nanomaterials in products … does not involve a significant social policy issue.” The company also claims its infant formula does not contain engineered nanomaterials, contrary to the independent laboratory testing.

“Walgreens is effectively silencing shareholder discussion of this subject,” said Austin Wilson, Environmental Health Program Manager of shareholder advocacy group As You Sow. “If Walgreens had responded to consumers’ and investors’ concerns, there would be no need for shareholders to file a proposal.”

“Shareholders will ultimately bear the burden of litigation if infants are harmed,” said Danielle Fugere, President and Chief Counsel of As You Sow. “Walgreens’ attempt to silence, rather than address, shareholder concerns raises red flags. To be successful, Walgreens must remain a trusted name for consumers and it can’t do that by sweeping new health studies under the rug.”

Nanoparticles are extremely small particles that can permeate cell membranes and travel throughout the body, including into organs, in ways that larger ingredients cannot. The extremely small size of nanoparticles may result in greater toxicity for human health and the environment.

The shareholder proposal asks the company to issue a report about actions the company is taking to reduce or eliminate the risk of nanoparticles.

In 2014, Dunkin’ Donuts reached an agreement with As You Sow to remove the nanoparticle titanium dioxide from its donuts. Starbucks plans to remove it from all products by 2017, and Krispy Kreme is reformulating its products to exclude titanium dioxide and other nanoparticles.

To seemingly dismiss concerns about their brand infant formula appears to be an odd tactic for Walgreens. After all this is infant safety and it’s the kind of thing that makes people very, very angry. On the other hand, Friends of the Earth has not always been scrupulous in its presentation of ‘facts’ (see my Feb. 9, 2012 posting).

2016 hasn’t been a good year for Walgreens. In June they ended their high profile partnership with blood testing startup, Theranos. From a June 13, 2016 article by Abigail Tracy for Vanity Fair,

After months of getting pummeled at the hands of regulators and the media over its questionable blood-testing technology, Theranos may have just been dealt its final blow. Walgreens, the main source of Theranos’s customers, has officially ended its partnership with the embattled biotech company, cutting off a critical revenue stream for founder Elizabeth Holmes’s once-promising start-up.

In a statement issued Sunday [June 12, 2016], the drugstore chain announced that it was terminating its nearly three-year-long relationship with the once $9 billion company and would immediately close all 40 Theranos-testing locations in its Arizona stores, The Wall Street Journal reports. Like so many in Silicon Valley, Walgreens fell victim to Holmes’s claims that Theranos’s technology, and its proprietary diagnostic product, Edison, would revolutionize blood testing and put its rivals, Laboratory Corporation of America and Quest Diagnostics, out of business. When it inked its deal with Holmes in 2013, Walgreens failed to properly vet the Edison technology, which was billed as being capable of conducting hundreds of diagnostics tests with just a few drops of blood.

You can read more about the Theranos situation in Tracy’s June 13, 2016 article and I have some details in a Sept. 2, 2016 posting where I feature the scandal and the proposed movie about Theranos (and other ‘science’ movies).

Getting back to Walgreens, you can find the As You Sow resolution here.

‘Potalyzer’ for roadside sobriety tests

Given the drive to legalize marijuana in Canada and in the US and the current crop of marijuana dispensaries in Vancouver (if nowhere else), this new ‘potalyzer’ test from Stanford University (California, US) seems quite timely and destined for popularity in police departments everywhere. From a Sept. 13, 2016 news item on Nanowerk,

This November [2016], several states will vote whether to legalize marijuana use, joining more than 20 states that already allow some form of cannabis use. This has prompted a need for effective tools for police to determine on the spot whether people are driving under the influence. Cars stopped while police interview drivers

Stanford researchers have devised a potential solution, applying magnetic nanotechnology, previously used as a cancer screen, to create what could be the first practical roadside test for marijuana intoxication.

While police are trying out potential tools, no device currently on the market has been shown to quickly provide a precise measurement of a driver’s marijuana intoxication as effectively as a breathalyzer gauges alcohol intoxication. THC, the drug’s most potent psychoactive agent, is commonly screened for in laboratory blood or urine tests – not very helpful for an officer in the field.

The Stanford device might function as a practical “potalyzer” because it can quickly detect not just the presence of THC in a person’s saliva, but also measure its concentration.

A Sept, 8, 2016 Stanford University news release by Carrie Kirby, which originated the news item, describes the technology in a little more detail,

Led by Shan Wang, a professor of materials science and engineering and of electrical engineering, the Stanford team created a mobile device that uses magnetic biosensors to detect tiny THC molecules in saliva. Officers could collect a spit sample with a cotton swab and read the results on a smartphone or laptop in as little as three minutes.

Researchers tackling the “potalyzer” problem have zeroed in on saliva because testing it is less invasive and because THC in saliva may correlate with impairment better than THC in urine or blood. The big challenge is that these spit tests may be called upon to detect superlatively tiny concentrations of THC. Some states have no set limit of THC in the body for drivers, while others set a limit of 0 or 5 nanograms (a billionth of a gram) per milliliter of blood.

Wang’s device can detect concentrations of THC in the range of 0 to 50 nanograms per milliliter of saliva. While there’s still no consensus on how much THC in a driver’s system is too much, previous studies have suggested a cutoff between 2 and 25 ng/mL, well within the capability of Wang’s device.

Repurposing biomedical tools

The researchers achieved such precision by harnessing the behavior of magnetism in nanoparticles, which measure just a few tens of billionths of a meter.

The Wang Group has been exploring magnetic nanotechnology for years, using it to attack such diverse problems as in vitro cancer diagnostics and magnetic information storage. In this case, they’re combining magnetic nanotechnology with the time-tested biochemical technique of the immunoassay. Immunoassays detect a certain molecule in a solution by introducing an antibody that will bind only to that molecule.

In the test, saliva is mixed with THC antibodies, which bind to any THC molecules in the sample. Then the sample is placed on a disposable chip cartridge, which contains magnetoresistive (GMR) sensors pre-coated with THC, and inserted into the handheld reader.

This sets in motion a “competition” between the THC pre-coated on the sensor and THC in the saliva to bind with the antibodies; the more THC in the saliva, the fewer antibodies will be available to bind to the THC on the sensor surface.

The number of antibodies bound to THC molecules on the sensor tells the device how many antibodies the THC in the sample used up, and therefore how many THC molecules were present in the sample.

Next, magnetic nanoparticles, specially made to bind only to the antibodies, are introduced to the sample. Each nanoparticle binds onto a THC-antibody pair like a sticky beacon, but only the molecules on the sensor surface will be close enough to trip the GMR biosensors in the reader. The device then uses Bluetooth to communicate results to the screen of a smartphone or laptop.

“To the best of our knowledge, this is the first demonstration that GMR biosensors are capable of detecting small molecules,” Wang wrote in a paper describing the device, published in Analytical Chemistry.

Beyond marijuana

The platform has potential usefulness beyond THC. Just as they do with THC, the GMR biosensors in the device could detect any small molecule, meaning that the platform could also test for morphine, heroin, cocaine or other drugs.

In fact, with 80 sensors built into it, the GMR biosensor chip could screen a single sample for multiple substances. The team has already tried screening for morphine with promising results.

Students are currently working on creating a user-friendly form factor for the device, which would need to go through field tests and be approved by regulators before it can be deployed by police.

Another thing that would have to happen before the device would be useful to law enforcement: State laws must set limits for the concentration of THC allowed in a driver’s saliva.

Here too, the Wang Group’s device could be helpful. For example, the next generation of the device could screen both the blood and saliva of a subject to establish an understanding of the correlation between blood THC level and saliva THC level at the same degree of intoxication.

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

Small Molecule Detection in Saliva Facilitates Portable Tests of Marijuana Abuse by Jung-Rok Lee, Joohong Choi, Tyler O. Shultz, and Shan X. Wang. Anal. Chem., 2016, 88 (15), pp 7457–7461 DOI: 10.1021/acs.analchem.6b01688 Publication Date (Web): July 19, 2016

Copyright © 2016 American Chemical Society

This paper is behind a paywall.

Nanoscale elements that govern the behaviour of our teeth

Are we going to be adopting atomically correct dental hygiene practices in the future? It’s certainly a possibility given the latest Australian research announced in a Sept. 7, 2016 news item on Nanowerk (Note: A link has been removed),

With one in two Australian children reported to have tooth decay in their permanent teeth by age 12, researchers from the University of Sydney believe they have identified some nanoscale elements that govern the behaviour of our teeth.

Material and structures engineers worked with dentists and bioengineers to map the exact composition and structure of tooth enamel at the atomic scale.

Using a relatively new microscopy technique called atom probe tomography, their work produced the first-ever three-dimensional maps showing the positions of atoms critical in the decay process.

The new knowledge on atom composition at the nanolevel has the potential to aid oral health hygiene and caries prevention, and has been published today in the journal Science Advances(“Atomic-scale compositional mapping reveals Mg-rich amorphous calcium phosphate in human dental enamel”).

A Sept. 8, 2016 University of Sydney press release, which originated the news item, expands on the theme (Note: A link has been removed),

Professor Julie Cairney, Material and Structures Engineer in the Faculty of Engineering and Information Technologies, said:

“The dental professionals have known that certain trace ions are important in the tough structure of tooth enamel but until now it had been impossible to map the ions in detail.

“The structure of human tooth enamel is extremely intricate and while we have known that magnesium, carbonate and fluoride ions influence enamel properties scientists have never been able to capture its structure at a high enough resolution or definition.”

“What we have found are the magnesium-rich regions between the hydroxyapatite nanorods that make up the enamel.”

“This means we have the first direct evidence of the existence of a proposed amorphous magnesium-rich calcium phosphate phase that plays an essential role in governing the behaviour of teeth. “

Co-lead researcher on the study, Dr Alexandre La Fontaine from the University’s Australian Centre for Microscopy and Microanalysis, said:

“We were also able to see nanoscale ‘clumps’ of organic material, which indicates that proteins and peptides are heterogeneously distributed within the enamel rather than present along all the nanorod interfaces, which was what was previously suggested.

“The mapping has the potential for new treatments designed around protecting against the dissolution of this specific amorphous phase.

“The new understanding of how enamel forms will also help in tooth remineralisation research.”

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

Atomic-scale compositional mapping reveals Mg-rich amorphous calcium phosphate in human dental enamel by Alexandre La Fontaine, Alexander Zavgorodniy, Howgwei Liu, Rongkun Zheng, Michael Swain, and Julie Cairney. Science Advances  07 Sep 2016: Vol. 2, no. 9, e1601145 DOI: 10.1126/sciadv.1601145

This paper is open access.