Tag Archives: nanotoxicology

Deadline extension (travel grants and poster abstracts) for alternate testing strategies (ATS) of nanomaterials workshop

It seems there have been a couple of deadline extensions (to August 1, 2014) for the September 15-16, 2014 ‘Workshop to Explore How a Multiple Models Approach can Advance Risk Analysis of Nanoscale Materials’ in Washington, DC (first mentioned in my July 10, 2014 posting featuring a description of the workshop). You can go here to submit a poster abstract (from any country) and you can go here if you’re a student or young professional (from any country) in search of a $500 travel award.

I managed to speak to one of the organizers, Lorraine Sheremeta, (Assistant Director, Ingenuity Lab, University of Alberta and co-author a July 9, 2014 Nanowerk Spotlight article about the workshop). Lorraine (Lori) kindly spoke to me about the upcoming workshop, which she described as an academic conference,.

As I understand what she told me, the hosts for the September 15-16, 2014 Workshop to Explore How a Multiple Models Approach can Advance Risk Analysis of Nanoscale Materials in Washington, DC want to attract a multidisciplinary group of people to grapple with a few questions. First, they want to establish a framework for establishing which are the best test methods for nanomaterials. Second, they are trying to move away from animal testing and want to establish which methods are equal to or better than animal testing. Thirdly, they want to discuss what they are going to do with the toxicological data  that we have  been collecting on nanomaterials for years now.

Or, as she and her colleague from the Society of Risk Analysis (Jo Anne Shatkin) have put in it in their Nanowerk Spotlight article:

… develop a report on the State of the Science for ATS for nanomaterials, catalogue of existing and emerging ATS [alternate testing strategies] methods in a database; and develop a case study to inform workshop deliberations and expert recommendations

The collaborative team behind this event includes, the University of Alberta’s Ingenuity Lab, the Society for Risk Analysis, Environment Canada, Health Canada, and the Organization for Economic Co-operation and Development (OECD) Working Party on Manufactured Nanomaterials (WPMN) .

The speaker lineup isn’t settled at this time although they have confirmed Vicki Stone of Heriot-Watt University in Scotland (from her university bio page),

Vicki Stone, Professor of Toxicology, studies the effects of nanomaterials on humans and environmentally relevant species.  Current research projects investigate the mechanism of toxicity of a range of nanomaterials in cells of the immune system (macrophages and neutrophils), liver (hepatocytes) , gastrointestinal tract, blood vessels (endothelium) and lung.  She is interested in interactions between nanomaterials, proteins and lipids, and how this influences subsequent toxicity.  Current projects also develop in vitro alternatives using microfluidics as well as high resolution imaging of individual nanomaterials in 3D and over time.  In addition Vicki collaborates with ecotoxicologists to investigate the impacts of nanomaterials on aquatic organisms. Vicki coordinated a European project to identify the research priorities to develop an intelligent testing strategy for nanomaterials (www.its-nano.eu).

Vicki is Director of the Nano Safety Research Group at Heriot-Watt University, Edinburgh, and Director of Toxicology for SAFENANO (www.safenano.org). She has acted as the Editor-in-chief of the journal Nanotoxicology (http://informahealthcare.com/nan) for 6 years (2006-2011). Vicki has also published over 130 publications pertaining to particle toxicology over the last 16 years and has provided evidence for the government commissioned reports published by the Royal Society (2003) and the on Environmental Pollution (2008).  Vicki was previously a member of the UK Government Committee on the Medical Effects of Air Pollution (COMEAP) and an advisory board member for the Center for the Environmental Implications of NanoTechnology (CEINT; funded by the US Environmental Protection Agency)).

A representative from PETA (People for the Ethical Treatment of Animals) will also be speaking. I believe that will be Amy Clippinger (from the PETA website’s Regulatory Testing webpage; scroll down about 70% of the way),

Science adviser Amy Clippinger has a Ph.D. in cellular and molecular biology and genetics and several years of research experience at the University of Pennsylvania.

PETA representatives have been to at least one other conference on the topic of nano, toxicology, and animal testing as per my April 24, 2014 posting about NANOTOX 2014 in Turkey,

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.

There is a lot of interest internationally in improving how we test for toxicity of nanomaterials. As well, the drive to eliminate or minimize as much as possible the use of animals in testing seems to be gaining momentum.

Good luck to everyone submitting a poster abstract and/or an application for a travel grant!

In case you don’t want to scroll up, the SRA nano workshop website is here.

An upcoming alternate testing strategies (ATS) for nanomaterials workshop and the quest to reduce animal testing

It’s too late to announce a call for poster abstracts or travel awards but that still leaves the possibility of attending a September 15-16, 2014 Workshop to Explore How a Multiple Models Approach can Advance Risk Analysis of Nanoscale Materials in Washington, DC. In a July 9, 2014 Nanowerk Spotlight article,, Jo Anne Shatkin (President, Vireo Advisors) and Lorraine Sheremeta (Assistant Director, Ingenuity Lab, University of Alberta) tout the workshop in the context of describing new approaches to nanotoxicology research (Note: A link has been removed),

Engineered nanoscale materials (ENM or ‘nanomaterials’) offer the potential to create safer and more effective products through the use of smaller quantities of improved performance materials. Currently nanomaterials are used to improve the performance of life-saving drugs and medical technologies, to make renewable energy more efficient, to make value added products from industrial waste streams, to improve food, packaging, to lightweight materials used in transportation systems, and to improve many of the personal care products that we use every day. Nanomaterial manufacture and use is expected to increase over the coming years and despite the widespread use of nanomaterials in a variety of consumer products, we are only beginning to understand the impacts of these emerging materials on our health and the environment. To this end, the University of Alberta’s Ingenuity Lab is collaborating with the Society for Risk Analysis to evaluate the potential to use alternative test strategies (ATS) to improve our ability to assess nanomaterial toxicity and environmental impact.

Shatkin and Sheremeta describe toxicology tests and explain the importance of refining and improving these tests (from the article),

Standard in vivo toxicology test methods that depend heavily on the use of animals have long been used to assess chemical safety. [emphasis mine*] Existing and novel in vitro and in silico test methods provide important alternatives to in vivo animal testing for chemicals and potentially for ENM. Genotoxicity tests, for example, are used to assess the mutagenic potential of chemicals or nanomaterials in the replication of DNA in cells. Driven in part by increasing market and regulatory requirements for safer and more sustainable products, large international infrastructure has developed for creating, testing and validating in vitro test methods, and its use is expanding to chemical and nanomaterial assessment (NSF, 2007). The goals of reducing, refining and replacing animal testing (the commonly cited ‘three Rs’) – resonate with key and diverse stakeholders including animal rights groups, the bioethics community, the pharmaceutical industry, regulatory agencies and the broader public. [emphasis mine*]

Despite nearly a decade of effort in the conduct toxicology and exposure research to inform the assessment of health and environmental risks of nanomaterials, major gaps remain in the ability to understand and quantify risks. While there is now a large body of published data on carbon nanotubes and metal oxide nanoparticles, concern has been raised that speculation about nanomaterial risk has hardened into an assumption that there are ‘as-yet-to-be-discovered risks’ that we must identify and manage (Maynard, 2014) that demands extensive testing.

The authors describe ATS (alternative test strategies) in greater detail,

ATS approaches are regarded by many to have the potential for rapid screening of large numbers and types of materials. They can include a breadth of techniques including high throughput screening methods (HTS), high content screening, computational approaches, toxicogenomics, cell-based methods, in vitro assays and non-mammalian whole animal models. The emergence of ATS raises questions about how the results of these methods may be used for assessing the potential risks of ENM. For instance, ATS could be used in combination in a multiple models approach to evaluate new ENM in a number of rapid assays and compare with well-studied substances using in vivo testing; thereby identifying ENM for additional testing in a more strategic fashion than is possible through conventional testing approaches.

They also describe the current state of affairs with ATS,

In the United States, the U.S. ToxCast program has, as part of their 21st century toxicity screening program (NRC, 2007), tested 29 NMs with 62 in vitro test methods (Wang et al. 2013). Many researchers, including several from the University of Alberta, have proposed and developed ATS to include a variety of methods, some which are standardized for chemicals, and others which take advantage of developments including advanced biological mechanistic understanding, genomics, metabolomics, automation and informatics. However, these existing as well as emerging ATS have a short history with nanomaterials, and have not yet proven to be reliable for quantitative estimation of ENM risk. Still, several international efforts have developed ATS that have potential to be used for screening purposes, and to guide further testing priorities for regulatory decision making. The goal of the September [2014] workshop by the Society for Risk Analysis is to explore ways in which distinct ATS may be used for screening and prioritizing the need for more extensive testing of novel ENM.

The parties (including the authors of the article) involved in developing this risk workshop are listed, also mentioned are members of the international testing scene,

Lori Sheremeta, the Assistant Director of Ingenuity Lab in Edmonton Alberta and past Chair of the Society for Risk Analysis (SRA) Emerging Nanoscale Materials Specialty Group (ENMSG), is collaborating with U.S.-based nanomaterials risk expert Jo Anne Shatkin (an SRA Councilor and co-founder of the SRA ENMSG), Environment Canada, Health Canada, the SRA ENMSG and others on a Pilot Project with the Organization for Economic Co-operation and Development (OECD) Working Party on Manufactured Nanomaterials (WPMN) to develop a report on the State of the Science for ATS for nanomaterials, catalogue of existing and emerging ATS methods in a database; and develop a case study to inform workshop deliberations and expert recommendations.

There are many international efforts to develop, as well as to validate and standardize, these methods for chemicals, including organizations such as the US National Toxicology Program Interagency Center for the Evaluation of Alternative Toxicological Methods (ICCVAM), the European Union Reference Laboratory European Centre for the Validation of Alternative Methods (EURL ECVAM), the Japanese Center for the Validation of Alternative Methods (JacVAM), the Korean Centre for the Validation of Alternative Methods (KoCVAM) and the OECD. There is wide recognition that the diversity of NMs renders it impractical to use traditional animal testing to evaluate safety, hence there is significant interest in assessing the performance of both existing and emerging alternative testing strategies for NMs. Further, the EU directive REACH (Directive 2006/121/EC) requires replacing in vivo testing, and there is widespread popular agreement about the desire to limit animal testing. Finally, there is a need for more biologically informative toxicology methods (Hartung, 2010; Silbergeld et al, 2011; Landsiedel et al, 2009).

A list of the workshop objectives is offered  in the article,

The main objectives of the workshop are to:

assess the state of the science on HTS and ATS from a ‘multiple models’ perspective to identify areas of common findings from differing approaches, areas of greatest uncertainty, and priorities for follow up in applied research toward risk assessment of ENM;
evaluate the ability to use data from ATS/HTS methods for screening purposes – combining suites of assays and comparing well-studied substances to novel ones;

assess the ability to use a suite of ATS methods to amplify the Weight of Evidence;

characterize uncertainty associated with predictive relationships and propose strategies to address uncertainties;

elicit the perspectives of diverse stakeholders about the use of HTS/ATS for screening purposes in risk analysis of ENM; and

develop a set of recommendations for these alternative approaches to become more widely adopted for environmental, health and safety decision making about ENM across the product life cycle. The output of the workshop holds potential for transformation through risk screening approaches that promote safer and more sustainable material and technology development.

You can find more about the September 15-16, 2014 Workshop to Explore How a Multiple Models Approach can Advance Risk Analysis of Nanoscale Materials in Washington, DC here.

The text in the article is a bit rough. Some of the ideas and topics don’t follow each other logically. So, be prepared to spend a little time reading, Happily, there are references included with the article.

I last mentioned Jo Anne Shatkin here in the context of a 2013 paper on alternative test strategies (ATS) in an Aug. 22, 2013 posting. I think the most recent mention of Lorraine Sheremeta here is in a Jan. 11, 2010 posting about Canada, nanotechnology, and food.

Final note, I am hoping to get some more information about the workshop and ATS scene from Lorraine Sheremeta to be published in a subsequent posting.

* I added the emphases at 0830 hours PDT July 10, 2014.

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).

New method for measuring risks and quantities of engineered nanomaterials delivered to cells

Despite all the talk about testing engineered nanoparticles and their possible effects on cells, there are problems with the testing process which researchers at the Harvard School of Public Health (HSPH) claim to have addressed (h/t Nanowerk, March 28, 2014).

A March 28, 2014 HSPH press release explains the interest in testing the effects of engineered nanomaterials/nanoparticles on health and describes some of the problems associated with testing their interaction with cells,

Thousands of consumer products containing engineered nanoparticles — microscopic particles found in everyday items from cosmetics and clothing to building materials — enter the market every year. Concerns about possible environmental health and safety issues of these nano-enabled products continue to grow with scientists struggling to come up with fast, cheap, and easy-to-use cellular screening systems to determine possible hazards of vast libraries of engineered nanomaterials. However, determining how much exposure to engineered nanoparticles could be unsafe for humans requires precise knowledge of the amount (dose) of nanomaterials interacting with cells and tissues such as lungs and skin.

With chemicals, this is easy to do but when it comes to nanoparticles suspended in physiological media, this is not trivial. Engineered nanoparticles in biological media interact with serum proteins and form larger agglomerates which alter both their so called effective density and active surface area and ultimately define their delivery to cell dose and bio-interactions. This behavior has tremendous implications not only in measuring the exact amount of nanomaterials interacting with cells and tissue but also in defining hazard rankings of various engineered nanomaterials (ENMs). As a result, thousands of published cellular screening assays are difficult to interpret and use for risk assessment purposes.

The press release goes on to describe the new technique (Note: Links have been removed),

Scientists at the Center for Nanotechnology and Nanotoxicology at Harvard School of Public Health (HSPH) have discovered a fast, simple, and inexpensive method to measure the effective density of engineered nanoparticles in physiological fluids, thereby making it possible to accurately determine the amount of nanomaterials that come into contact with cells and tissue in culture.

The method, referred to as the Volumetric Centrifugation Method (VCM), was published in the March 28, 2014 Nature Communications.

The new discovery will have a major impact on the hazard assessment of engineered nanoparticles, enabling risk assessors to perform accurate hazard rankings of nanomaterials using cellular systems. Furthermore, by measuring the composition of nanomaterial agglomerates in physiologic fluids, it will allow scientists to design more effective nano-based drug delivery systems for nanomedicine applications.

“The biggest challenge we have in assessing possible health effects associated with nano exposures is deciding when something is hazardous and when it is not, based on the dose level. At low levels, the risks are probably miniscule,” said senior author Philip Demokritou, associate professor of aerosol physics in the Department of Environmental Health at HSPH. “The question is: At what dose level does nano-exposure become problematic? The same question applies to nano-based drugs when we test their efficiency using cellular systems. How much of the administered nano-drug will come in contact with cells and tissue? This will determine the effective dose needed for a given cellular response,” Demokritou said.

Federal regulatory agencies do not require manufacturers to test engineered nanoparticles, if the original form of the bulk material has already been shown to be safe. However, there is evidence that some of these materials could be more harmful in the nanoscale — a scale at which materials may penetrate cells and bypass biological barriers more easily and exhibit unique physical, chemical, and biological properties compared to larger size particles. Nanotoxicologists are struggling to develop fast and cheap toxicological screening cellular assays to cope with the influx of vast forms of engineered nanomaterials and avoid laborious and expensive animal testing. However, this effort has been held back due to the lack of a simple-to-use, fast, method to measure the dose-response relationships and possible toxicological implications. While biological responses are fairly easy to measure, scientists are struggling to develop a fast method to assess the exact amount or dose of nanomaterials coming in contact with cells in biological media.

“Dosimetric considerations are too complicated to consider in nano-bio assessments, but too important to ignore,” Demokritou said. “Comparisons of biological responses to nano-exposures usually rely on guesstimates based on properties measured in the dry powder form (e.g., mass, surface area, and density), without taking into account particle-particle and particle-fluid interactions in biological media. When suspended in fluids, nanoparticles typically form agglomerates that include large amounts of the suspending fluid, and that therefore have effective densities much lower than that of dry material. This greatly influences the particle delivery to cells, and reduces the surface area available for interactions with cells,” said Glen DeLoid, research associate in the Department of Environmental Health, one of the two lead authors of the study. “The VCM method will help nanobiologists and regulators to resolve conflicting in vitro cellular toxicity data that have been reported in the literature for various nanomaterials. These disparities likely result from lack of or inaccurate dosimetric considerations in nano-bio interactions in a cellular screening system,” said Joel Cohen, doctoral student at HSPH and one of the two lead authors of the study.

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

Estimating the effective density of engineered nanomaterials for in vitro dosimetry by Glen DeLoid, Joel M. Cohen, Tom Darrah, Raymond Derk, Liying Rojanasakul, Georgios Pyrgiotakis, Wendel Wohlleben, & Philip Demokritou. Nature Communications 5, Article number: 3514 doi:10.1038/ncomms4514 Published 28 March 2014

This paper is behind a paywall but a free preview is available via ReadCube Access.

Ecotoxicology and environmental fate of manufactured nanomaterials—testing guidelines from Organization for Economic Cooperation and Development (OECD)

The Organization for Economic Cooperation and Development (OECD) has released guidelines for testing manufactured nanomaterials according to a March 11, 2014 news item on Nanowerk,

As part of its Programme on the Safety of Manufactured Nanomaterials, and in particular work on the testing and assessment of manufactured nanomaterials, OECD initiated a series of expert meetings to improve the applicability of the OECD Test Guidelines to nanomaterials. With this in mind, the Working Party on Manufactured Nanomaterials agreed to address the ecotoxicology and environmental fate of manufactured nanomaterials.

The OECD Expert Meeting on Ecotoxicology and Environmental Fate took place on 29th-31st January 2013 in Berlin, Federal Press Office. The event was hosted by the German delegation and funded by the German Federal Ministry of the Environment, Nature Conservation and Nuclear Safety (BMU) as well as the United States Environment Protection Agency (US EPA).

Three documents were published one of which being a preview,

The OECD expert meeting on ecotoxicology and environmental fate — Towards the development of improved OECD guidelines for the testing of nanomaterials by Dana Kühnel and Carmen Nickel. Science of The Total Environment Volume 472, 15 February 2014, Pages 347–353 http://dx.doi.org/10.1016/j.scitotenv.2013.11.055

This document is open access.

The report itself,

OECD. ENVIRONMENT DIRECTORATE.
JOINT MEETING OF THE CHEMICALS COMMITTEE AND
THE WORKING PARTY ON CHEMICALS, PESTICIDES AND BIOTECHNOLOGY. Environment, Health and Safety Publications
Series on the Safety of Manufactured Nanomaterials. ENV/JM/MONO(2014)1

ECOTOXICOLOGY AND ENVIRONMENTAL FATE OF MANUFACTURED NANOMATERIALS:
TEST GUIDELINES Expert Meeting Report
Series on the Safety of Manufactured Nanomaterials No. 40

Ecotoxicology and Environmental Fate of Manufactured Nanomaterials: Test Guidelines

There’s an addendum which includes the presentations made at the meeting (you can find both the report, proper, and the addendum on this page scroll to report no. 40),

OECD. ENVIRONMENT DIRECTORATE JOINT MEETING OF THE CHEMICALS COMMITTEE AND
THE WORKING PARTY ON CHEMICALS, PESTICIDES AND BIOTECHNOLOGY. Environment, Health and Safety Publications. ENV/JM/MONO(2014)1/ADD

ADDENDUM TO EXOTOXICOLOGY AND ENVIRONMENTAL FATE OF MANUFACTURED
NANOMATERIALS: TEST GUIDELINES

Series on the Safety of Manufactured Nanomaterials No. 40
Ecotoxicology and Environmental Fate of Manufactured Nanomaterials:
Test Guidelines.

As it can get a little tricky accessing OECD documents, I’ve tried to give a couple different links and as much identifying information as possible. Good luck!

Danish scientists provide insights into celllular response to silver nanoparticles

The conclusions are concerning but the scientists at the University of Southern Denmark are careful to note that this research on silver nanopartices was performed in a laboratory setting which does not necessarily predict what might happen under real life conditions.

As for the research itself, a Feb. 28, 2014 news item on Azonano has this to say,

Endocrine disrupters are not the only worrying chemicals that ordinary consumers are exposed to in everyday life. Also nanoparticles of silver, found in e.g. dietary supplements, cosmetics and food packaging, now worry scientists. A new study from the University of Southern Denmark shows that nano-silver can penetrate our cells and cause damage.

Silver has an antibacterial effect and therefore the food and cosmetic industry often coat their products with silver nanoparticles. Nano-silver can be found in e.g. drinking bottles, cosmetics, band aids, toothbrushes, running socks, refrigerators, washing machines and food packagings.

“Silver as a metal does not pose any danger, but when you break it down to nano-sizes, the particles become small enough to penetrate a cell wall. If nano-silver enters a human cell, it can cause changes in the cell”, explain Associate Professor Frank Kjeldsen and PhD Thiago Verano-Braga, Department of Biochemistry and Molecular Biology at the University of Southern Denmark.

A Feb. 27, 2014 University of Southern Denmark news release, which originated the news item, provides more detail about the research,

The researchers examined human intestinal cells, as they consider these to be most likely to come into contact with nano-silver, ingested with food.

“We can confirm that nano-silver leads to the formation of harmful, so called free radicals in cells. We can also see that there are changes in the form and amount of proteins. This worries us”, say Frank Kjeldsen and Thiago Verano-Braga.

A large number of serious diseases are characterized by the fact that there is an overproduction of free radicals in cells. This applies to cancer and neurological diseases such as Alzheimer’s and Parkinson’s.

Kjeldsen and Verano-Braga emphasizes that their research is conducted on human cells in a laboratory, not based on living people. They also point out that they do not know how large a dose of nano-silver, a person must be exposed to for the emergence of cellular changes.

“We don’t know how much is needed, so we cannot conclude that nano-silver can make you sick. But we can say that we must be very cautious and worried when we see an overproduction of free radicals in human cells”, they say.

Nano-silver is also sold as a dietary supplement, promising to have an antibacterial, anti-flu and cancer-inhibatory effect. The nano-silver should also help against low blood counts and bad skin. In the EU, the marketing of dietary supplements and foods with claims to have medical effects is not allowed. But the nano-silver is easy to find and buy online.

In the wake of the SDU-research, the Danish Veterinary and Food Administration now warns against taking dietary supplements with nano-silver.

“The recent research strongly suggests that it can be dangerous”, says Søren Langkilde from the Danish Veterinary and Food Administration to the Danish Broadcasting Corporation (DR).

The researchers supplied this image to illustrate the abstract for their paper (link and citation to follow),

Courtesy University of Southern Denmark

Courtesy University of Southern Denmark

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

Insights into the Cellular Response Triggered by Silver Nanoparticles Using Quantitative Proteomics by Thiago Verano-Braga, Rona Miethling-Graff, Katarzyna Wojdyla, Adelina Rogowska-Wrzesinska, Jonathan R. Brewer, Helmut Erdmann, and Frank Kjeldsen. ACS Nano, Article ASAP DOI: 10.1021/nn4050744 Publication Date (Web): February 10, 2014
Copyright © 2014 American Chemical Society

This paper is behind a paywall.

Silver ions in the environment

Earlier this week (Feb. 24, 2014), I published a post featuring Dr. Andrew Maynard, Director of the University of Michigan’s Risk Science Center in an introductory video describing seven surprising facts about silver nanoparticles. For those who want to delve more deeply, there’s a Feb. 25, 2014 news item on Nanowerk describing some Swiss research into silver nanoparticles and ions in aquatic environments,

It has long been known that, in the form of free ions, silver particles can be highly toxic to aquatic organisms. Yet to this day, there is a lack of detailed knowledge about the doses required to trigger a response and how the organisms deal with this kind of stress. To learn more about the cellular processes that occur in the cells, scientists from the Aquatic Research Institute, Eawag [Swiss Federal Institute of Aquatic Science and Technology], subjected algae to a range of silver concentrations.

In the past, silver mostly found its way into the environment in the vicinity of silver mines or via wastewater [emphasis mine] emanating from the photo industry. More recently, silver nanoparticles have become commonplace in many applications – as ingredients in cosmetics, food packaging, disinfectants, and functional clothing. Though a recent study conducted by the Swiss National Science Foundation revealed that the bulk of silver nanoparticles is retained in wastewater treatment plants, only little is known about the persistence and the impact of the residual nano-silver in the environment.

The Feb. 25, 2014 Eawag media release, which originated the news item, describes the research in further detail,

Smitha Pillai from the Eawag Department of Environmental Toxicology and her colleagues from EPF Lausanne and ETH Zürich studied the impact of various concentrations of waterborne silver ions on the cells of the green algae Chlamydomonas reinhardtii. Silver is chemically very similar to copper, an essential metal due to its importance in several enzymes. Because of that, silver can exploit the cells’ copper transport mechanisms and sneak into them undercover. This explains why, already after a short time, concentrations of silver in the intracellular fluid can reach up to one thousand times those in the surrounding environment.

A prompt response

Because silver damages key enzymes involved in energy metabolism, even low concentrations can cut photosynthesis and growth rates by a half in just 15 minutes. Over the same time period, the researchers also detected changes in the activity of about 1000 other genes and proteins, which they interpreted as a response to the stressor – an attempt to repair silver-induced damage. At low concentrations, the cells’ photosynthesis apparatus recovered within five hours, and recovery mechanisms were sufficient to deal with all but the highest concentrations tested.

A number of unanswered questions

At first glance, the results are reassuring because the silver concentrations that the algae are subject to in the environment are rarely as high as those applied in the lab, which allows them to recover quickly – at least externally. But the experiments also showed that even low silver concentrations have a significant effect on intracellular processes and that the algae divert their energy to repairing damage incurred. This can pose a problem when other stressors act in parallel, such as increased UV-radiation or other chemical compounds. Moreover, it remains unknown to this day whether the cells have an active mechanism to shuttle out the silver. Lacking such a mechanism, the silver could have adverse effects on higher organisms, given that algae are at the bottom of the food chain.

You can find the researchers’ paper here,

Linking toxicity and adaptive responses across the transcriptome, proteome, and phenotype of Chlamydomonas reinhardtii exposed to silver by Smitha Pillai, Renata Behra, Holger Nestler, Marc J.-F. Suter, Laura Sigg, and Kristin Schirmer. Proceedings of the National Academy of Sciences (PNAS) – early edition 18.February 2014, www.pnas.org/cgi/doi/10.1073/pnas.1319388111

The paper is available through the PNAS open access option.

I have published a number of pieces about aquatic enviornments and wastewater and nanotechnology-enabled products as useful for remediation efforts and as a source of pollution. Here’s a Feb. 28, 2013 posting where I contrasted two pieces of research on silver nanoparticles. The first was research in an aquatic environment and the other concerned wastewater.

Czech veterinary research institute tracks nanoparticles

When I first saw the Jan. 7, 2014 news item on Azonano, I was expecting to see some cute animal images mixed with the ‘nano’ talk. While there’s no mild amusement to be had, there is plenty of ‘nano’ talk concerning the work being done at the Veterinary Research Institute (Brno,  Czech republic) on characterizing nanoparticles using some new equipment (Note: Links have been removed),

Malvern [which owns the company, NanoSight] reports on how NanoSight’s Nanoparticle Tracking Analysis, NTA, is being applied in the Veterinary Research Institute, Brno, Czech Republic in the research group of Dr. Jaroslav Turanek in the Department of Pharmacology and Immunotherapy).

The central theme of Dr. Jaroslav Turanek’s research group (Department of Pharmacology and Immunotherapy) at the Veterinary Research Institute in Brno is to apply synthetic and bioorganic chemistry. This work is performed in collaboration with King’s College London and the Institute of Organic Chemistry and Biochemistry, Prague, for the design and construction of therapeutic nanoparticles to develop drug delivery systems (anticancer and antiviral drugs) and nanocarriers for construction of recombinant vaccines.

In parallel, the research group of Dr. Miroslav Machala (Department of Chemistry and Toxicology) at Veterinary Research Institute focuses upon environmental nanoparticulate pollutants. Characterization of airborne particles is conducted using electron microscopy, but in vitro tests on cell culture require knowledge of the real structure of nanoparticles in the tissue culture medium (e.g. aggregation). This enables the group to draw the correct conclusions from in vitro toxicological experiments which can be affected by differences in local nanoparticle concentration owing to sedimentation. Detailed particle distribution and kinetics of aggregation in this heterogeneous system is impossible to obtain using electron microscopy and hence Nanoparticle Tracking Analysis, NTA, is the method of choice. It is noted that some metastable aggregates can disaggregate due to high dilution of the sample required for NTA analysis. For this reason, Dynamic Light Scattering, DLS, and NTA are used as suitable complementary methods in the laboratory.

The Jan. 7, 2014 Malvern Instruments press release on biospace.com, which originated the news item, provides a quote from Dr. Jaroslav Turanek’ describing the NTA system,

Explaining their choice of NanoSight, Dr Turanek said “We chose NTA as a convenient and rapid method for characterization of nanoparticles in heterogeneous preparations like liposomes and their complexes with proteins, DNA and polysaccharides. A set of these techniques is used for the complex characterization of the structure of the nanoparticles, the kinetics of their preparation, the dynamics of morphological transformation and, finally, their stability. NTA perfectly fits our needs and has become a standard method in our methodological portfolio. The most advantageous feature of NTA is that it makes it possible to visualize each nanoparticle and then to obtain more detailed size distributions based on individual particle measurements. DLS is used as precise complementary method for the characterization of nanoparticles below 20 nm for proteins and other biopolymers. Combination of these two methods, NTA and DLS, with separation methods (GPC, FFF) and electron microscopy is preferred to get the full insight to structure and dynamics of nanoparticles in our sample systems.”

It took me quite a while to realize that nanoparticles in a sample are not necessarily homogenous, i.e., similar in size, etc. Unconsciously, I had applied my notions of manufacturing where items are made (stamped, poured into moulds, etc.)  to be identical. As far as I’m aware there is no such production process for nanoparticles which makes characterizing them an important task if the purpose is to better understand their properties.

You can find out more about Malvern Instruments here and about NanoSight here.

Human immune system and nanotoxicology in Québec (Canada)

At this point it’s starting to seem like there are thousands and thousands of nanotoxicology studies so the announcement of a new study based in Québec (Canada) didn’t immediately cause excitement  until I caught sight of the word ‘inflammation” which casts a newish light on the topic. From the Dec. 4, 2013 news item on Azonano,

… Professor Girard [Professor Denis Girard INRS–Institut Armand-Frappier Research Centre] will focus on the effects of NPs [nanoparticles] on human immune system cells (eosinophils) that play a key role in inflammation.

“Several studies on NPs have examined how tissues react in contact with these tiny foreign bodies,” said Girard. “Researchers have found that eosinophils flock to the contact site, but they have not examined the phenomenon in greater detail.” To further investigate why eosinophils come into contact with NPs and the role they play, protocols require expertise in both nanotoxicology and immunology, which is rare.

The Nov. 28, 2013 INRS [Institut national de la recherche scientifique] Université news release by Stéphanie Thibault, which originated the news item, delves into the issue of inflammatory responses,

According to Professor Girard, understanding the inflammatory response is currently a priority in the field of nanotoxicology. For a number of years, researchers have been observing links between exposure to NPs and asthmatic symptoms in some animals. Does the human body undergo similar inflammation upon contact with NPs? In the absence of any standards for workers, it’s best to take a closer look, insists Girard. “At this time, nanoparticles have not been properly identified and are often handled without protection. If they enter the body through the skin, respiratory tract, or even ingestion, we have no idea what happens next.” In his lab, a variety of approaches will help further understanding of how nanoparticles of different types and sizes interact. Cellular processes will be examined in detail.

 

At the rate at which NPs are being developed, Girard could be conducting systematic nanotoxicology studies for many years to come. “I will of course need the support of a strong team,” said Girard. “I already have one I am very proud of, and it will be expanded for the new project.” …

I gather there are going to be some jobs generated from this grant,

His research is being funded by Institut de recherche Robert-Sauvé en santé et en sécurité du travail (IRSST), which will award him a renewable $300,000 grant for the next three years.

… The IRSST grant will be used to hire staff and student researchers.

While I have heard of the IRSST before,, the INRS is new to me. Here’s more from the INRS English language homepage,

INRS (Institut national de la recherche scientifique) is one of Canada’s top universities in terms of research intensity (funding per faculty member). It brings together 150 professors, over 700 graduate and postgraduate students, and a hundred postdoctoral researchers at four centers in Montreal, Québec City, Laval, and Varennes. Conducting applied and fundamental research essential to the advancement of science in Quebec and around the world, our research teams plays a critical role in finding solutions to problems facing our society. Founded in 1969, INRS is one of the nine establishments that make up the Université du Québec network.

 

“The Institute is dedicated to fundamental and applied research, graduate studies, and the training of researchers. In keeping with its mission and objectives as a research university, the Institute specifically gears its activities towards Quebec’s economic, social, and cultural development, as well as the transfer of knowledge and technology stemming from all its fields of study.” INRS letters patent, 1999

There you have it.