Category Archives: risk

Rapid formation of micro- and nanoplastics in the environment

Image: Nora Meides.

A June 18, 2021 news item on announces the results of research into how materials made of plastic break down into micro- and nanoplastic particles in the environment,

Most microplastic particles in the environment originate from larger pieces of plastic. In a long-term study, an interdisciplinary research team at the University of Bayreuth has simulated how quickly plastic breaks down into fragments under natural influences. High-tech laboratory tests on polystyrene show two phases of abiotic degradation. To begin with, the stability of the plastic is weakened by photo-oxidation. Then cracks form and more and more and smaller fragments are released into the environment. The study, published in the journal Environmental Science & Technology, allows conclusions to be drawn about other plastics that are common in the environment.

A June 17, 2021 University of Bayreuth press release, which originated the news item, provides more detail,

Polystyrene is an inexpensive plastic that is often used for packaging and thermal insulation, and is therefore particularly common in plastic waste. As part of their long-term study, the Bayreuth researchers for the first time combined analytical investigations, which were also carried out on polystyrene particles at the atomic level, with measurements determining the behaviour of these particles under mechanical stress. On the basis of this, they developed a model for abiotic degradation, i.e. degradation without the influence of living organisms.

“Our study shows that a single microplastic particle with a diameter of 160 micrometres releases about 500 particles in the order of 20 micrometres – i.e. 0.02 millimetres – over the course of one and a half years of being exposed to natural weathering processes in the environment. Over time, these particles in turn break down into smaller and smaller fragments. An ecocorona can form around these tiny particles, possibly facilitating penetration into the cells of living organisms. This was discovered a few months ago by another Bayreuth research group,” says first author Nora Meides, a doctoral student in macromolecular chemistry at the University of Bayreuth.

n the water, the microplastic particles were exposed to two stress factors: intense sunlight and continuous mechanical stress produced by agitation. In the real-world environment, sunlight and mechanical stress are in fact the two main abiotic factors that contribute to the gradual fragmentation of the particles. Irradiation by sunlight triggers oxidation processes on the surface of the particles. This photo-oxidation, in combination with mechanical stress, has significant consequences. The polystyrene chains become ever shorter. Furthermore, they become increasingly polar, i.e. centres of charge are formed in the molecules. In the second phase, the microplastic particles begin to fragment. Here, the particles break down into smaller and smaller micro- and nanoplastic fragments.

“Our research results are a valuable basis for investigating the abiotic degradation of macro- and microplastics in the environment – both on land and at the surface of water – in more detail, using other types of plastic as examples. We were surprised by the speed of fragmentation ourselves, which again shows the potential risks that could emanate from the growing burden of plastics on the environment. Especially larger plastic waste objects, are – when exposed to sunlight and abrasion – a reservoir of constant microplastic input. It is precisely these tiny particles, barely visible to the naked eye, that spread to the remotest ecosystems via various transport routes,” says Teresa Menzel, PhD student in the area of Polymer Engineering.

“The polystyrene investigated in our long-term study has a carbon-chain backbone, just like polyethylene and polypropylene. It is very likely that the two-phase model we have developed on polystyrene can be transferred to these plastics,” adds lead author Prof. Dr. Jürgen Senker, Professor of Inorganic Chemistry, who coordinated the research work. 

The study that has now been published is the result of the close interdisciplinary cooperation of a working group belonging to the DFG Collaborative Research Centre “Microplastics” at the University of Bayreuth. In this team, scientists from macromolecular chemistry, inorganic chemistry, engineering science, and animal ecology are jointly researching the formation and degradation of microplastics. Numerous types of research technology are available on the Bayreuth campus for this purpose, which were used in the long-term study: among others, ¹³C-MAS-NMR spectroscopy, energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and gel permeation chromatography (GPC).

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

Reconstructing the Environmental Degradation of Polystyrene by Accelerated Weathering by Nora Meides, Teresa Menzel, Björn Poetzschner, Martin G. J. Löder, Ulrich Mansfeld, Peter Strohriegl, Volker Altstaedt, and Jürgen Senker. Environ. Sci. Technol. 2021, 55, 12, 7930–7938 DOI: Publication Date: May 21, 2021 Copyright © 2021 The Authors. Published by American Chemical Society

This paper is behind a paywall.

Use AI to reduce worries about nanoparticles in food

A June 16, 2021 news item on ScienceDaily announces research into the impact that engineered metallic nanoparticles used in agricultural practices have on food,

While crop yield has achieved a substantial boost from nanotechnology in recent years, alarms over the health risks posed by nanoparticles within fresh produce and grains have also increased. In particular, nanoparticles entering the soil through irrigation, fertilizers and other sources have raised concerns about whether plants absorb these minute particles enough to cause toxicity.

In a new study published online in the journal Environmental Science and Technology, researchers at Texas A&M University have used machine learning [a form of artificial intelligence {AI}] to evaluate the salient properties of metallic nanoparticles that make them more susceptible for plant uptake. The researchers said their algorithm could indicate how much plants accumulate nanoparticles in their roots and shoots.

A June 16, 2021 Texas A&M University news release (also on EurekAlert), which originated the news item, describes the research, which employed two different machine learning algorithms, in more detail,

Nanoparticles are a burgeoning trend in several fields, including medicine, consumer products and agriculture. Depending on the type of nanoparticle, some have favorable surface properties, charge and magnetism, among other features. These qualities make them ideal for a number of applications. For example, in agriculture, nanoparticles may be used as antimicrobials to protect plants from pathogens. Alternatively, they can be used to bind to fertilizers or insecticides and then programmed for slow release to increase plant absorption.

These agricultural practices and others, like irrigation, can cause nanoparticles to accumulate in the soil. However, with the different types of nanoparticles that could exist in the ground and a staggeringly large number of terrestrial plant species, including food crops, it is not clearly known if certain properties of nanoparticles make them more likely to be absorbed by some plant species than others.

“As you can imagine, if we have to test the presence of each nanoparticle for every plant species, it is a huge number of experiments, which is very time-consuming and expensive,” said Xingmao “Samuel” Ma, associate professor in the Zachry Department of Civil and Environmental Engineering. “To give you an idea, silver nanoparticles alone can have hundreds of different sizes, shapes and surface coatings, and so, experimentally testing each one, even for a single plant species, is impractical.”

Instead, for their study, the researchers chose two different machine learning algorithms, an artificial neural network and gene-expression programming. They first trained these algorithms on a database created from past research on different metallic nanoparticles and the specific plants in which they accumulated. In particular, their database contained the size, shape and other characteristics of different nanoparticles, along with information on how much of these particles were absorbed from soil or nutrient-enriched water into the plant body.

Once trained, their machine learning algorithms could correctly predict the likelihood of a given metallic nanoparticle to accumulate in a plant species. Also, their algorithms revealed that when plants are in a nutrient-enriched or hydroponic solution, the chemical makeup of the metallic nanoparticle determines the propensity of accumulation in the roots and shoots. But if plants are grown in soil, the contents of organic matter and the clay in soil are key to nanoparticle uptake.

Ma said that while the machine learning algorithms could make predictions for most food crops and terrestrial plants, they might not yet be ready for aquatic plants. He also noted that the next step in his research would be to investigate if the machine learning algorithms could predict nanoparticle uptake from leaves rather than through the roots.

“It is quite understandable that people are concerned about the presence of nanoparticles in their fruits, vegetables and grains,” said Ma. “But instead of not using nanotechnology altogether, we would like farmers to reap the many benefits provided by this technology but avoid the potential food safety concerns.”

This image accompanies the paper’s research abstract,

[downloaded frm]

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

Prediction of Plant Uptake and Translocation of Engineered Metallic Nanoparticles by Machine Learning by Xiaoxuan Wang, Liwei Liu, Weilan Zhang, and Xingmao Ma. Environ. Sci. Technol. 2021, 55, 11, 7491–7500 DOI: Publication Date:May 17, 2021 Copyright © 2021 American Chemical Society

This paper is behind a paywall.

A library of properties for nanomaterials

Researchers at the University of Birmingham (UK) announced the development of a library of nanomaterial properties according to a June 8, 2021 news item on Nanowerk (Note: Links have been removed),

Researchers have developed a ‘library of properties’ to help identify the environmental impact of nanomaterials faster and more cost effectively.

Whilst nanomaterials have benefited a wide range of industries and revolutionized everyday life, there are concerns over potential adverse effects—including toxic effects following accumulation in different organs and indirect effects from transport of co-pollutants.

The European Union H2020-funded NanoSolveIT project is developing a ground-breaking computer-based Integrated Approach to Testing and Assessment (IATA) for the environmental health and safety of nanomaterials.

A June 8, 2021 University of Birmingham press release (also on EurekAlert) spells out the details,

Over the last two years, researchers from the University of Birmingham have worked with experts at NovaMechanics, in Nicosia, Cyprus to develop a decision support system in the form of both stand-alone open software and a Cloud platform.

The team has developed a freely available cloud library containing full physicochemical characterisation of 69 nanomaterials, plus calculated molecular descriptors to increase the value of the available information, details of which are published in NanoImpact. [link and citation follow]

Professor Iseult Lynch, from the University of Birmingham commented: “One of the limitations to widespread application of computer-based approaches is the lack of large well-organised high-quality datasets, or of data with adequate metadata that will allow dataset interoperability and their combination to create larger datasets.”

“Making the library of calculated and experimental descriptors available to the community, along with the detailed description of how they were calculated is a key first step towards filling this datagap.”

Development of the cloud-based nanomaterials library is the fifth freely available web-based application that the project has delivered.

Antreas Afantitis, from NovaMechanics, commented: “Over the last two years, this project has already presented some very impressive results with more than 30 publications, making NanoSolveIT one of the most active projects in the nanomaterials safety and informatics space.”

Concerns about nanomaterials are also arising as risk assessment is lagging behind product development, mainly because current approaches to assessing exposure, hazard and risk are expensive and time-consuming, and frequently involve testing in animal models. The NanoSolveIT project aspires to address these challenges.

The latest development aims to enrich our knowledge of nanomaterials properties and the link from property to (cytotoxic) effect. The enriched dataset contains over 70 descriptors per nanomaterial.

The dataset was used to develop a computer-based workflow to predict nanomaterials’ effective surface charge (zeta-potential) based on a set of descriptors that can be used to help design and produce safer and more functional nanomaterials.

The resulting predictive read-across model has been made publicly and freely available as a web service through the Horizon 2020 (H2020) NanoCommons project ( ) and via the H2020 NanoSolveIT Cloud Platform ( ) to ensure accessibility to the community and interested stakeholders.

In addition, the full data set, ready for further computational modeling, is available through the NanoPharos database, as the project consortium supports the FAIR data principles – committing to making its data Findable, Accessible, Interoperable and Re-usable.

I quite like this image of how the scales are illustrated (BTW, you can find NanoSolveIT here the NanoCommons project [closing date May 15, 2021] here, and NovaMechanics here)

Scales of descriptors – from whole nanoparticle to unit cell to individual atoms Courtesy University of Birmingham and NanoSolveIT

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

Computational enrichment of physicochemical data for the development of a ζ-potential read-across predictive model with Isalos Analytics Platform by Anastasios G. Papadiamantis, Antreas Afantitis, Andreas Tsoumanis, Eugenia Valsami-Jones, Iseult Lynch, Georgia Melagraki. NanoImpact Volume 22, April 2021, 100308 DOI: Available online 18 March 2021

This paper is open access.

Canadian and Guadeloupean oysters: exposure to nanoplastics and arsenic

A May 27, 2021 news item on describes research into oysters and nanoplastics,

Oysters’ exposure to plastics is concerning, particularly because these materials can accumulate and release metals which are then absorbed by the mollusks. According to a recent study published in the journal Chemosphere, the combined presence of nanoplastics and arsenic affects the biological functions of oysters. This study was conducted by the Institut national de la recherche scientifique (INRS) in Québec City and the French National Centre for Scientific Research (CNRS) at the University of Bordeaux in France

A May 27, 2021 INRS news release (French language version here and an English language version on EurekAlert), which originated the news item, provides fascinating details,

The international research team chose to study arsenic, since it is one of the most common metals absorbed by the plastic debris collected from the beaches of Guadeloupe. “Oysters easily accumulate metals from the environment into their tissues. We therefore wanted to test whether the combined exposure to nanoplastics and arsenic would increase the bioaccumulation of this contaminant,” reported Marc Lebordais, the Master’s student in charge of the research.

The scientists proved that the bioaccumulation of arsenic does not increase when nanoplastics are also present. However, it remained higher in the gills of the Canadian Crassostrea virginica oyster [emphasis mine] than in the Isognomon alatus oyster, found in Guadeloupe. These results are the first to highlight the diverging sensitivity of different species. [emphasis mine]

Gene deregulation

In addition to bioaccumulation, the team also observed an overexpression of genes responsible for cell death and the number of mitochondria–a cell’s energy centres–in C. virginica. In I. alatus, the expression of these same genes was less significant.

“Evaluating the expression of genes involved in important functions, such as cell death and detoxification, gives us information on the toxicity of nanoplastics and arsenic on a cellular level,” explained the young researcher, who is co-directed by Professors Valérie Langlois of INRS and Magalie Baudrimont of the University of Bordeaux.

The food chain

The next step, after characterizing the presence of nanoplastics and arsenic in oysters, would be to study how these contaminants are transferred through the food chain.

“Analytical tools are currently being developed to quantify the presence of nanoplastics in biological tissues,” said Marc Lebordais. “Understanding the amount of nanoplastics in farmed oysters currently boils down to a technical issue.” ?

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

Molecular impacts of dietary exposure to nanoplastics combined with arsenic in Canadian oysters (Crassostrea virginica) and bioaccumulation comparison with Caribbean oysters (Isognomon alatus) by Marc Lebordais, Juan Manuel Gutierrez-Villagomez, Julien Gigault, Magalie Baudrimont, and Valérie Langlois. Chemosphere Volume 277, August 2021, 130331 DOI: First published online 19 March 2021.

This paper is open access.

Five country survey of reactions to food genome editing

Weirdly and even though most of this paper’s authors are from the University of British Columbia (UBC; Canada), only one press release was issued and that was by the lead author’s (Gesa Busch) home institution, the University of Göttingen (Germany).

I’m glad Busch, the other authors, and the work are getting some attention (if not as much as I think they should).

From a July 9, 2021 University of Göttingen press release (also on EurekAlert but published on July 12, 2021),

A research team from the University of Göttingen and the University of British Columbia (Canada) has investigated how people in five different countries react to various usages of genome editing in agriculture. The researchers looked at which uses are accepted and how the risks and benefits of the new breeding technologies are rated by people. The results show only minor differences between the countries studied – Germany, Italy, Canada, Austria and the USA. In all countries, making changes to the genome is more likely to be deemed acceptable when used in crops rather than in livestock. The study was published in Agriculture and Human Values.

Relatively new breeding technologies, such as CRISPR [clustered regularly interspaced short palindromic repeats) gene editing, have enabled a range of new opportunities for plant and animal breeding. In the EU, the technology falls under genetic engineering legislation and is therefore subject to rigorous restrictions. However, the use of gene technologies remains controversial. Between June and November 2019, the research team collected views on this topic via online surveys from around 3,700 people from five countries. Five different applications of gene editing were evaluated: three relate to disease resistance in people, plants, or animals; and two relate to achieving either better quality of produce or a larger quantity of product from cattle.

“We were able to observe that the purpose of the gene modification plays a major role in how it is rated,” says first author Dr Gesa Busch from the University of Göttingen. “If the technology is used to make animals resistant to disease, approval is greater than if the technology is used to increase the output from animals.” Overall, however, the respondents reacted very differently to the uses of the new breeding methods. Four different groups can be identified: strong supporters, supporters, neutrals, and opponents of the technology. The opponents (24 per cent) identify high risks and calls for a ban of the technology, regardless of possible benefits. The strong supporters (21 per cent) see few risks and many advantages. The supporters (26 per cent) see many advantages but also risks. Whereas those who were neutral (29 per cent) show no strong opinion on the subject.

This study was made possible through funding from the Free University of Bozen-Bolzano and Genome BC.

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

Citizen views on genome editing: effects of species and purpose by Gesa Busch, Erin Ryan, Marina A. G. von Keyserlingk & Daniel M. Weary. Agriculture and Human Values (2021) Published: DOI:

This paper is open access.


I have one quick comment about the methodology. It can be difficult to get a sample that breaks down along demographic lines that is close to or identical to national statistics. That said, it was striking to me that every country was under represented in the ’60 years+ ‘ category. In Canada, it was by 10 percentage points (roughly). For other countries the point spread was significantly wider. In Italy, it was a 30 percentage point spread (roughly).

I found the data in the Supplementary Materials yesterday (July 13, 2021). When I looked this morning, that information was no longer there but you will find what appears to be the questionnaire. I wonder if this removal is temporary or permanent and, if permanent, I wonder why it was removed.

Participants for the Canadian portion of the survey were supplied by Dynata, a US-based market research company. Here’s the company’s Wikipedia entry and its website.

Information about how participants were recruited was also missing this morning (July 14, 2021).

Genome British Columbia (Genome BC)

I was a little surprised when I couldn’t find any information about the program or the project on the Genome BC website as the organization is listed as a funder.

There is a ‘Genomics and Society’ tab (seems promising, eh?) on the homepage where you can find the answer to this question: What is GE³LS Research?,

GE3LS research is interdisciplinary, conducted by researchers across many disciplines within social science and humanities, including economics, environment, law, business, communications, and public policy.

There’s also a GE3LS Research in BC page titled Project Search; I had no luck there either.

It all seems a bit mysterious to me and, just in case anything else disappears off the web, here’s a July 13, 2021 news item about the research on as backup to what I have here.

Health Canada advisory: Face masks that contain graphene may pose health risks

Since COVID-19, we’ve been advised to wear face masks. It seems some of them may not be as safe as we assumed. First, the Health Canada advisory that was issued today, April 2, 2021 and then excerpts from an in-depth posting by Dr. Andrew Maynard (associate dean in the Arizona State University College of Global Futures) about the advisory and the use of graphene in masks.

From the Health Canada Recalls & alerts: Face masks that contain graphene may pose health risks webpage,


  • Product: Face masks labelled to contain graphene or biomass graphene.
  • Issue: There is a potential that wearers could inhale graphene particles from some masks, which may pose health risks.
  • What to do: Do not use these face masks. Report any health product adverse events or complaints to Health Canada.


Health Canada is advising Canadians not to use face masks that contain graphene because there is a potential that they could inhale graphene particles, which may pose health risks.

Graphene is a novel nanomaterial (materials made of tiny particles) reported to have antiviral and antibacterial properties. Health Canada conducted a preliminary scientific assessment after being made aware that masks containing graphene have been sold with COVID-19 claims and used by adults and children in schools and daycares. Health Canada believes they may also have been distributed for use in health care settings.

Health Canada’s preliminary assessment of available research identified that inhaled graphene particles had some potential to cause early lung toxicity in animals. However, the potential for people to inhale graphene particles from face masks and the related health risks are not yet known, and may vary based on mask design. The health risk to people of any age is not clear. Variables, such as the amount and duration of exposure, and the type and characteristics of the graphene material used, all affect the potential to inhale particles and the associated health risks. Health Canada has requested data from mask manufacturers to assess the potential health risks related to their masks that contain graphene.

Until the Department completes a thorough scientific assessment and has established the safety and effectiveness of graphene-containing face masks, it is taking the precautionary approach of removing them from the market while continuing to gather and assess information. Health Canada has directed all known distributors, importers and manufacturers to stop selling and to recall the affected products. Additionally, Health Canada has written to provinces and territories advising them to stop distribution and use of masks containing graphene. The Department will continue to take appropriate action to stop the import and sale of graphene face masks.

Products affected

Face masks labelled as containing graphene or biomass graphene.

What you should do

  • Do not use face masks labelled to contain graphene or biomass graphene.
  • Consult your health care provider if you have used graphene face masks and have health concerns, such as new or unexplained shortness of breath, discomfort or difficulty breathing.
  • Report any health product adverse events or complaints regarding graphene face masks to Health Canada.

Dr. Andrew Maynard’s Edge of Innovation series features a March 26, 2021 posting about the use of graphene in masks (Note: Links have been removed),

Face masks should protect you, not place you in greater danger. However, last Friday Radio Canada revealed that residents of Quebec and Ottawa were being advised not to use specific types of graphene-containing masks as they could potentially be harmful.

The offending material in the masks is graphene — a form of carbon that consists of nanoscopically thin flakes of hexagonally-arranged carbon atoms. It’s a material that has a number of potentially beneficial properties, including the ability to kill bacteria and viruses when they’re exposed to it.

Yet despite its many potential uses, the scientific jury is still out when it comes to how safe the material is.

As with all materials, the potential health risks associated with graphene depend on whether it can get into the body, where it goes if it can, what it does when it gets there, and how much of it is needed to cause enough damage to be of concern.

Unfortunately, even though these are pretty basic questions, there aren’t many answers forthcoming when it comes to the substance’s use in face masks.

Early concerns around graphene were sparked by previous research on another form of carbon — carbon nanotubes. It turns out that some forms of these fiber-like materials can cause serious harm if inhaled. And following on from research here, a natural next-question to ask is whether carbon nanotubes’ close cousin graphene comes with similar concerns.

Because graphene lacks many of the physical and chemical aspects of carbon nanotubes that make them harmful (such as being long, thin, and hard for the body to get rid of), the indications are that the material is safer than its nanotube cousins. But safer doesn’t mean safe. And current research indicates that this is not a material that should be used where it could potentially be inhaled, without a good amount of safety testing first.

[downloaded from] Original source: Wikimedia

When it comes to inhaling graphene, the current state of the science indicates that if the material can get into the lower parts of the lungs (the respirable or alveolar region) it can lead to an inflammatory response at high enough concentrations.

There is some evidence that adverse responses are relatively short-lived, and that graphene particles can be broken down and disposed of by the lungs’ defenses.

This is good news as it means that there are less likely to be long-term health impacts from inhaling the material.

There’s also evidence that graphene, unlike some forms of thin, straight carbon nanotubes, does not migrate to the outside layers of the lungs where it could potentially do a lot more damage.

Again, this is encouraging as it suggests that graphene is unlikely to lead to serious long-term health impacts like mesothelioma.

However, research also shows that this is not a benign material. Despite being made of carbon — and it’s tempting to think of carbon as being safe, just because we’re familiar with it — there is some evidence that the jagged edges of some graphene particles can harm cells, leading to local damage as the body responds to any damage the material causes.

There are also concerns, although they are less well explored in the literature, that some forms of graphene may be carriers for nanometer-sized metal particles that can be quite destructive in the lungs. This is certainly the case with some carbon nanotubes, as the metallic catalyst particles used to manufacture them become embedded in the material, and contribute to its toxicity.

The long and short of this is that, while there are still plenty of gaps in our knowledge around how much graphene it’s safe to inhale, inhaling small graphene particles probably isn’t a great idea unless there’s been comprehensive testing to show otherwise.

And this brings us to graphene-containing face masks.


Here, it’s important to stress that we don’t yet know if graphene particles are being released and, if they are, whether they are being released in sufficient quantities to cause health effects. And there are indications that, if there are health risks, these may be relatively short-term — simply because graphene particles may be effectively degraded by the lungs’ defenses.

At the same time, it seems highly irresponsible to include a material with unknown inhalation risks in a product that is intimately associated with inhalation. Especially when there are a growing number of face masks available that claim to use graphene.

… There are millions of graphene face masks and respirators being sold and used around the world. And while the unfolding news focuses on Quebec and one particular type of face mask, this is casting uncertainty over the safety of any graphene-containing masks that are being sold.

And this uncertainty will persist until manufacturers and regulators provide data indicating that they have tested the products for the release and subsequent inhalation of fine graphene particles, and shown the risks to be negligible.

I strongly recommend reading, in its entirety , Dr. Maynard’s March 26, 2021 posting, Which he has updated twice since first posting the story.

In short. you may want to hold off before buying a mask with graphene until there’s more data about safety.

Could synergistic action of engineered nanoparticles have a health impact?

Synergistic action can be difficult to study especially when you’re looking at nanoparticles which could be naturally occurring and/or engineered. I believe this study is focused on engineered nanoparticles (ENPs) and I think it’s the first one I’ve seen that examines synergistic action of any kind. So, bravo to the scientists for tackling a very ambitious project.

An October 1, 2020 news item on describes this work from Denmark,

Nanoparticles are used in a wide range of products and manufacturing processes because the properties of a material can change dramatically when the material comes in nano-form.

They can be used, for example, to purify wastewater and to transport medicine around the body. They are also added to, for example, socks, pillows, mattresses, phone covers and refrigerators to supply the items with an antibacterial surface.

Much research has been done on how nanoparticles affect humans and the environment and a number of studies have shown that nanoparticles can disrupt or damage our cells.

This is confirmed by a new study that has also looked at how cells react when exposed to more than one kind of nano particle at the same time.

An October 1, 2020 University of Southern Denmark press release (also on EurekAlert) by Birgitte Svennevig, which originated the news item, provides more insight into the research,

The lead author of the study is Barbara Korzeniowska from the Department of Biochemistry and Molecular Biology at SDU. The head of research is Professor Frank Kjeldsen from the same department.

His research into metal nanoparticles is supported by a European Research Grant of DKK 14 million.

“Throughout a lifetime, we are exposed to many different kinds of nano-particles, and we should investigate how the combination of different nano-particles affects us and also whether an accumulation through life can harm us,” says Barbara Korzeniowska.

She herself became interested in the subject when her little daughter one day was going in the bathtub and got a rubber duck as a toy.

– It turned out that it had been treated with nano-silver, probably to keep it free of bacteria, but small children put their toys in their mouths, and she could thus ingest nano-silver. That is highly worrying when research shows that nano-silver can damage human cells, she says.

In her new study, she looked at nano-silver and nano-platinum. She has investigated their individual effect and whether exposure of both types of nanoparticles results in a synergy effect in two types of brain cells.

– There are almost no studies of the synergy effect of nano particles, so it is important to get started with these studies, she says.

She chose nano-silver because it is already known to be able to damage cells and nano-platinum, because nano-platinum is considered to be so-called bio-inert; i.e. has a minimal interaction with human tissue.

The nanoparticles were tested on two types of brain cells: astrocytes and endothelial cells. Astrocytes are supporter cells in the central nervous system, which i.a. helps to supply the nervous system with nutrients and repair damage to the brain. Endothelial cells sit on the inside of the blood vessels and transport substances from the bloodstream to the brain.

When the endothelial cells were exposed to nano-platinum, nothing happened. When exposed to nano-silver, their ability to divide deteriorated. When exposed to both nano-silver and nano-platinum, the effect was amplified, and they died in large numbers. Furthermore, their defense mechanisms decreased, and they had difficulty communicating with each other.

– So even though nano-platinum alone does not do harm, something drastic happens when they are combined with a different kind of nano-particle, says Frank Kjeldsen.

The astrocytes were more hardy and reacted “only” with impaired ability to divide when exposed to both types of nano-particles.

An earlier study, conducted by Frank Kjeldsen, has shown a dramatic synergy effect of silver nanoparticles and cadmium ions, which are found naturally all around us on Earth.

In that study, 72 % of the cells died (in this study it was intestinal cells) as they were exposed to both nano-silver and cadmium ions. When they were only exposed to nano-silver, 25% died. When exposed to cadmium ions only, 12% died.

We are involuntarily exposed

– Little is known about how large concentrations of nano-particles are used in industrial products. We also do not know what size particles they use – size also has an effect on whether they can enter a cell, says Barbara Korzeniowska and continues:

– But we know that a lot of people are involuntarily exposed to nano-particles, and that there can be lifelong exposure.

There are virtually no restrictions on adding nanoparticles to products. In the EU, however, manufacturers must have an approval if they want to use nanoparticles in products with antibacterial properties. In Denmark, they must also declare nano-content in such products on the label.

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

The Cytotoxicity of Metal Nanoparticles Depends on Their Synergistic Interactions by Barbara Korzeniowska, Micaella P. Fonseca, Vladimir Gorshkov, Lilian Skytte, Kaare L. Rasmussen, Henrik D. Schrøder, Frank Kjeldsen. Particle Volume 37, Issue 8, August 2020,. 2000135 DOI: First published: 06 July 2020

This paper is behind a paywall.

Food sensor made from of silk microneedles looks like velco

These sensors really do look like velcro,

The Velcro-like food sensor, made from an array of silk microneedles, can pierce through plastic packaging to sample food for signs of spoilage and bacterial contamination. Image: Felice Frankel

A September 9, 2020 news item on Nanowerk announces some research from the Massachusetts Institute (MIT),

MIT engineers have designed a Velcro-like food sensor, made from an array of silk microneedles, that pierces through plastic packaging to sample food for signs of spoilage and bacterial contamination.

The sensor’s microneedles are molded from a solution of edible proteins found in silk cocoons, and are designed to draw fluid into the back of the sensor, which is printed with two types of specialized ink. One of these “bioinks” changes color when in contact with fluid of a certain pH range, indicating that the food has spoiled; the other turns color when it senses contaminating bacteria such as pathogenic E. coli.

A Sept. 9, 2020 MIT news release (also on EurekAlert), which originated the news item, delves further into the research,

The researchers attached the sensor to a fillet of raw fish that they had injected with a solution contaminated with E. coli. After less than a day, they found that the part of the sensor that was printed with bacteria-sensing bioink turned from blue to red — a clear sign that the fish was contaminated. After a few more hours, the pH-sensitive bioink also changed color, signaling that the fish had also spoiled.

The results, published today in the journal Advanced Functional Materials, are a first step toward developing a new colorimetric sensor that can detect signs of food spoilage and contamination.

Such smart food sensors might help head off outbreaks such as the recent salmonella contamination in onions and peaches. They could also prevent consumers from throwing out food that may be past a printed expiration date, but is in fact still consumable.

“There is a lot of food that’s wasted due to lack of proper labeling, and we’re throwing food away without even knowing if it’s spoiled or not,” says Benedetto Marelli, the Paul M. Cook Career Development Assistant Professor in MIT’s Department of Civil and Environmental Engineering. “People also waste a lot of food after outbreaks, because they’re not sure if the food is actually contaminated or not. A technology like this would give confidence to the end user to not waste food.”

Marelli’s co-authors on the paper are Doyoon Kim, Yunteng Cao, Dhanushkodi Mariappan, Michael S. Bono Jr., and A. John Hart.

Silk and printing

The new food sensor is the product of a collaboration between Marelli, whose lab harnesses the properties of silk to develop new technologies, and Hart, whose group develops new manufacturing processes.

Hart recently developed a high-resolution floxography technique, realizing microscopic patterns that can enable low-cost printed electronics and sensors. Meanwhile, Marelli had developed a silk-based microneedle stamp that penetrates and delivers nutrients to plants. In conversation, the researchers wondered whether their technologies could be paired to produce a printed food sensor that monitors food safety.

“Assessing the health of food by just measuring its surface is often not good enough. At some point, Benedetto mentioned his group’s microneedle work with plants, and we realized that we could combine our expertise to make a more effective sensor,” Hart recalls.

The team looked to create a sensor that could pierce through the surface of many types of food. The design they came up with consisted of an array of microneedles made from silk.

“Silk is completely edible, nontoxic, and can be used as a food ingredient, and it’s mechanically robust enough to penetrate through a large spectrum of tissue types, like meat, peaches, and lettuce,” Marelli says.

A deeper detection

To make the new sensor, Kim first made a solution of silk fibroin, a protein extracted from moth cocoons, and poured the solution into a silicone microneedle mold. After drying, he peeled away the resulting array of microneedles, each measuring about 1.6 millimeters long and 600 microns wide — about one-third the diameter of a spaghetti strand.

The team then developed solutions for two kinds of bioink — color-changing printable polymers that can be mixed with other sensing ingredients. In this case, the researchers mixed into one bioink an antibody that is sensitive to a molecule in E. coli. When the antibody comes in contact with that molecule, it changes shape and physically pushes on the surrounding polymer, which in turn changes the way the bioink absorbs light. In this way, the bioink can change color when it senses contaminating bacteria.

The researchers made a bioink containing antibodies sensitive to E. coli, and a second bioink sensitive to pH levels that are associated with spoilage. They printed the bacteria-sensing bioink on the surface of the microneedle array, in the pattern of the letter “E,” next to which they printed the pH-sensitive bioink, as a “C.” Both letters initially appeared blue in color.

Kim then embedded pores within each microneedle to increase the array’s ability to draw up fluid via capillary action. To test the new sensor, he bought several fillets of raw fish from a local grocery store and injected each fillet with a fluid containing either E. coli, Salmonella, or the fluid without any contaminants. He stuck a sensor into each fillet. Then, he waited.

After about 16 hours, the team observed that the “E” turned from blue to red, only in the fillet contaminated with E. coli, indicating that the sensor accurately detected the bacterial antigens. After several more hours, both the “C” and “E” in all samples turned red, indicating that every fillet had spoiled.

The researchers also found their new sensor indicates contamination and spoilage faster than existing sensors that only detect pathogens on the surface of foods.

“There are many cavities and holes in food where pathogens are embedded, and surface sensors cannot detect these,” Kim says. “So we have to plug in a bit deeper to improve the reliability of the detection. Using this piercing technique, we also don’t have to open a package to inspect food quality.”

The team is looking for ways to speed up the microneedles’ absorption of fluid, as well as the bioinks’ sensing of contaminants. Once the design is optimized, they envision the sensor could be used at various stages along the supply chain, from operators in processing plants, who can use the sensors to monitor products before they are shipped out, to consumers who may choose to apply the sensors on certain foods to make sure they are safe to eat.

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

A Microneedle Technology for Sampling and Sensing Bacteria in the Food Supply Chain by Doyoon Kim, Yunteng Cao, Dhanushkodi Mariappan, Michael S. Bono Jr., A. John Hart, Benedetto Marelli. DOI: First published: 09 September 2020

This paper is behind a paywall.

Turning brain-controlled wireless electronic prostheses into reality plus some ethical points

Researchers at Stanford University (California, US) believe they have a solution for a problem with neuroprosthetics (Note: I have included brief comments about neuroprosthetics and possible ethical issues at the end of this posting) according an August 5, 2020 news item on ScienceDaily,

The current generation of neural implants record enormous amounts of neural activity, then transmit these brain signals through wires to a computer. But, so far, when researchers have tried to create wireless brain-computer interfaces to do this, it took so much power to transmit the data that the implants generated too much heat to be safe for the patient. A new study suggests how to solve his problem — and thus cut the wires.

Caption: Photo of a current neural implant, that uses wires to transmit information and receive power. New research suggests how to one day cut the wires. Credit: Sergey Stavisky

An August 3, 2020 Stanford University news release (also on EurekAlert but published August 4, 2020) by Tom Abate, which originated the news item, details the problem and the proposed solution,

Stanford researchers have been working for years to advance a technology that could one day help people with paralysis regain use of their limbs, and enable amputees to use their thoughts to control prostheses and interact with computers.

The team has been focusing on improving a brain-computer interface, a device implanted beneath the skull on the surface of a patient’s brain. This implant connects the human nervous system to an electronic device that might, for instance, help restore some motor control to a person with a spinal cord injury, or someone with a neurological condition like amyotrophic lateral sclerosis, also called Lou Gehrig’s disease.

The current generation of these devices record enormous amounts of neural activity, then transmit these brain signals through wires to a computer. But when researchers have tried to create wireless brain-computer interfaces to do this, it took so much power to transmit the data that the devices would generate too much heat to be safe for the patient.

Now, a team led by electrical engineers and neuroscientists Krishna Shenoy, PhD, and Boris Murmann, PhD, and neurosurgeon and neuroscientist Jaimie Henderson, MD, have shown how it would be possible to create a wireless device, capable of gathering and transmitting accurate neural signals, but using a tenth of the power required by current wire-enabled systems. These wireless devices would look more natural than the wired models and give patients freer range of motion.

Graduate student Nir Even-Chen and postdoctoral fellow Dante Muratore, PhD, describe the team’s approach in a Nature Biomedical Engineering paper.

The team’s neuroscientists identified the specific neural signals needed to control a prosthetic device, such as a robotic arm or a computer cursor. The team’s electrical engineers then designed the circuitry that would enable a future, wireless brain-computer interface to process and transmit these these carefully identified and isolated signals, using less power and thus making it safe to implant the device on the surface of the brain.

To test their idea, the researchers collected neuronal data from three nonhuman primates and one human participant in a (BrainGate) clinical trial.

As the subjects performed movement tasks, such as positioning a cursor on a computer screen, the researchers took measurements. The findings validated their hypothesis that a wireless interface could accurately control an individual’s motion by recording a subset of action-specific brain signals, rather than acting like the wired device and collecting brain signals in bulk.

The next step will be to build an implant based on this new approach and proceed through a series of tests toward the ultimate goal.

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

Power-saving design opportunities for wireless intracortical brain–computer interfaces by Nir Even-Chen, Dante G. Muratore, Sergey D. Stavisky, Leigh R. Hochberg, Jaimie M. Henderson, Boris Murmann & Krishna V. Shenoy. Nature Biomedical Engineering (2020) DOI: Published: 03 August 2020

This paper is behind a paywall.

Comments about ethical issues

As I found out while investigating, ethical issues in this area abound. My first thought was to look at how someone with a focus on ability studies might view the complexities.

My ‘go to’ resource for human enhancement and ethical issues is Gregor Wolbring, an associate professor at the University of Calgary (Alberta, Canada). his profile lists these areas of interest: ability studies, disability studies, governance of emerging and existing sciences and technologies (e.g. neuromorphic engineering, genetics, synthetic biology, robotics, artificial intelligence, automatization, brain machine interfaces, sensors) and more.

I can’t find anything more recent on this particular topic but I did find an August 10, 2017 essay for The Conversation where he comments on technology and human enhancement ethical issues where the technology is gene-editing. Regardless, he makes points that are applicable to brain-computer interfaces (human enhancement), Note: Links have been removed),

Ability expectations have been and still are used to disable, or disempower, many people, not only people seen as impaired. They’ve been used to disable or marginalize women (men making the argument that rationality is an important ability and women don’t have it). They also have been used to disable and disempower certain ethnic groups (one ethnic group argues they’re smarter than another ethnic group) and others.

A recent Pew Research survey on human enhancement revealed that an increase in the ability to be productive at work was seen as a positive. What does such ability expectation mean for the “us” in an era of scientific advancements in gene-editing, human enhancement and robotics?

Which abilities are seen as more important than others?

The ability expectations among “us” will determine how gene-editing and other scientific advances will be used.

And so how we govern ability expectations, and who influences that governance, will shape the future. Therefore, it’s essential that ability governance and ability literacy play a major role in shaping all advancements in science and technology.

One of the reasons I find Gregor’s commentary so valuable is that he writes lucidly about ability and disability as concepts and poses what can be provocative questions about expectations and what it is to be truly abled or disabled. You can find more of his writing here on his eponymous (more or less) blog.

Ethics of clinical trials for testing brain implants

This October 31, 2017 article by Emily Underwood for Science was revelatory,

In 2003, neurologist Helen Mayberg of Emory University in Atlanta began to test a bold, experimental treatment for people with severe depression, which involved implanting metal electrodes deep in the brain in a region called area 25 [emphases mine]. The initial data were promising; eventually, they convinced a device company, St. Jude Medical in Saint Paul, to sponsor a 200-person clinical trial dubbed BROADEN.

This month [October 2017], however, Lancet Psychiatry reported the first published data on the trial’s failure. The study stopped recruiting participants in 2012, after a 6-month study in 90 people failed to show statistically significant improvements between those receiving active stimulation and a control group, in which the device was implanted but switched off.

… a tricky dilemma for companies and research teams involved in deep brain stimulation (DBS) research: If trial participants want to keep their implants [emphases mine], who will take responsibility—and pay—for their ongoing care? And participants in last week’s meeting said it underscores the need for the growing corps of DBS researchers to think long-term about their planned studies.

… participants bear financial responsibility for maintaining the device should they choose to keep it, and for any additional surgeries that might be needed in the future, Mayberg says. “The big issue becomes cost [emphasis mine],” she says. “We transition from having grants and device donations” covering costs, to patients being responsible. And although the participants agreed to those conditions before enrolling in the trial, Mayberg says she considers it a “moral responsibility” to advocate for lower costs for her patients, even it if means “begging for charity payments” from hospitals. And she worries about what will happen to trial participants if she is no longer around to advocate for them. “What happens if I retire, or get hit by a bus?” she asks.

There’s another uncomfortable possibility: that the hypothesis was wrong [emphases mine] to begin with. A large body of evidence from many different labs supports the idea that area 25 is “key to successful antidepressant response,” Mayberg says. But “it may be too simple-minded” to think that zapping a single brain node and its connections can effectively treat a disease as complex as depression, Krakauer [John Krakauer, a neuroscientist at Johns Hopkins University in Baltimore, Maryland] says. Figuring that out will likely require more preclinical research in people—a daunting prospect that raises additional ethical dilemmas, Krakauer says. “The hardest thing about being a clinical researcher,” he says, “is knowing when to jump.”

Brain-computer interfaces, symbiosis, and ethical issues

This was the most recent and most directly applicable work that I could find. From a July 24, 2019 article by Liam Drew for Nature Outlook: The brain,

“It becomes part of you,” Patient 6 said, describing the technology that enabled her, after 45 years of severe epilepsy, to halt her disabling seizures. Electrodes had been implanted on the surface of her brain that would send a signal to a hand-held device when they detected signs of impending epileptic activity. On hearing a warning from the device, Patient 6 knew to take a dose of medication to halt the coming seizure.

“You grow gradually into it and get used to it, so it then becomes a part of every day,” she told Frederic Gilbert, an ethicist who studies brain–computer interfaces (BCIs) at the University of Tasmania in Hobart, Australia. “It became me,” she said. [emphasis mine]

Gilbert was interviewing six people who had participated in the first clinical trial of a predictive BCI to help understand how living with a computer that monitors brain activity directly affects individuals psychologically1. Patient 6’s experience was extreme: Gilbert describes her relationship with her BCI as a “radical symbiosis”.

Symbiosis is a term, borrowed from ecology, that means an intimate co-existence of two species for mutual advantage. As technologists work towards directly connecting the human brain to computers, it is increasingly being used to describe humans’ potential relationship with artificial intelligence.

Interface technologies are divided into those that ‘read’ the brain to record brain activity and decode its meaning, and those that ‘write’ to the brain to manipulate activity in specific regions and affect their function.

Commercial research is opaque, but scientists at social-media platform Facebook are known to be pursuing brain-reading techniques for use in headsets that would convert users’ brain activity into text. And neurotechnology companies such as Kernel in Los Angeles, California, and Neuralink, founded by Elon Musk in San Francisco, California, predict bidirectional coupling in which computers respond to people’s brain activity and insert information into their neural circuitry. [emphasis mine]

Already, it is clear that melding digital technologies with human brains can have provocative effects, not least on people’s agency — their ability to act freely and according to their own choices. Although neuroethicists’ priority is to optimize medical practice, their observations also shape the debate about the development of commercial neurotechnologies.

Neuroethicists began to note the complex nature of the therapy’s side effects. “Some effects that might be described as personality changes are more problematic than others,” says Maslen [Hannah Maslen, a neuroethicist at the University of Oxford, UK]. A crucial question is whether the person who is undergoing stimulation can reflect on how they have changed. Gilbert, for instance, describes a DBS patient who started to gamble compulsively, blowing his family’s savings and seeming not to care. He could only understand how problematic his behaviour was when the stimulation was turned off.

Such cases present serious questions about how the technology might affect a person’s ability to give consent to be treated, or for treatment to continue. [emphases mine] If the person who is undergoing DBS is happy to continue, should a concerned family member or doctor be able to overrule them? If someone other than the patient can terminate treatment against the patient’s wishes, it implies that the technology degrades people’s ability to make decisions for themselves. It suggests that if a person thinks in a certain way only when an electrical current alters their brain activity, then those thoughts do not reflect an authentic self.

To observe a person with tetraplegia bringing a drink to their mouth using a BCI-controlled robotic arm is spectacular. [emphasis mine] This rapidly advancing technology works by implanting an array of electrodes either on or in a person’s motor cortex — a brain region involved in planning and executing movements. The activity of the brain is recorded while the individual engages in cognitive tasks, such as imagining that they are moving their hand, and these recordings are used to command the robotic limb.

If neuroscientists could unambiguously discern a person’s intentions from the chattering electrical activity that they record in the brain, and then see that it matched the robotic arm’s actions, ethical concerns would be minimized. But this is not the case. The neural correlates of psychological phenomena are inexact and poorly understood, which means that signals from the brain are increasingly being processed by artificial intelligence (AI) software before reaching prostheses.[emphasis mine]

But, he [Philipp Kellmeyer, a neurologist and neuroethicist at the University of Freiburg, Germany] says, using AI tools also introduces ethical issues of which regulators have little experience. [emphasis mine] Machine-learning software learns to analyse data by generating algorithms that cannot be predicted and that are difficult, or impossible, to comprehend. This introduces an unknown and perhaps unaccountable process between a person’s thoughts and the technology that is acting on their behalf.

Maslen is already helping to shape BCI-device regulation. She is in discussion with the European Commission about regulations it will implement in 2020 that cover non-invasive brain-modulating devices that are sold straight to consumers. [emphases mine; Note: There is a Canadian company selling this type of product, MUSE] Maslen became interested in the safety of these devices, which were covered by only cursory safety regulations. Although such devices are simple, they pass electrical currents through people’s scalps to modulate brain activity. Maslen found reports of them causing burns, headaches and visual disturbances. She also says clinical studies have shown that, although non-invasive electrical stimulation of the brain can enhance certain cognitive abilities, this can come at the cost of deficits in other aspects of cognition.

Regarding my note about MUSE, the company is InteraXon and its product is MUSE.They advertise the product as “Brain Sensing Headbands That Improve Your Meditation Practice.” The company website and the product seem to be one entity, Choose Muse. The company’s product has been used in some serious research papers they can be found here. I did not see any research papers concerning safety issues.

Getting back to Drew’s July 24, 2019 article and Patient 6,

… He [Gilbert] is now preparing a follow-up report on Patient 6. The company that implanted the device in her brain to help free her from seizures went bankrupt. The device had to be removed.

… Patient 6 cried as she told Gilbert about losing the device. … “I lost myself,” she said.

“It was more than a device,” Gilbert says. “The company owned the existence of this new person.”

I strongly recommend reading Drew’s July 24, 2019 article in its entirety.


It’s easy to forget that in all the excitement over technologies ‘making our lives better’ that there can be a dark side or two. Some of the points brought forth in the articles by Wolbring, Underwood, and Drew confirmed my uneasiness as reasonable and gave me some specific examples of how these technologies raise new issues or old issues in new ways.

What I find interesting is that no one is using the term ‘cyborg’, which would seem quite applicable.There is an April 20, 2012 posting here titled ‘My mother is a cyborg‘ where I noted that by at lease one definition people with joint replacements, pacemakers, etc. are considered cyborgs. In short, cyborgs or technology integrated into bodies have been amongst us for quite some time.

Interestingly, no one seems to care much when insects are turned into cyborgs (can’t remember who pointed this out) but it is a popular area of research especially for military applications and search and rescue applications.

I’ve sometimes used the term ‘machine/flesh’ and or ‘augmentation’ as a description of technologies integrated with bodies, human or otherwise. You can find lots on the topic here however I’ve tagged or categorized it.

Amongst other pieces you can find here, there’s the August 8, 2016 posting, ‘Technology, athletics, and the ‘new’ human‘ featuring Oscar Pistorius when he was still best known as the ‘blade runner’ and a remarkably successful paralympic athlete. It’s about his efforts to compete against able-bodied athletes at the London Olympic Games in 2012. It is fascinating to read about technology and elite athletes of any kind as they are often the first to try out ‘enhancements’.

Gregor Wolbring has a number of essays on The Conversation looking at Paralympic athletes and their pursuit of enhancements and how all of this is affecting our notions of abilities and disabilities. By extension, one has to assume that ‘abled’ athletes are also affected with the trickle-down effect on the rest of us.

Regardless of where we start the investigation, there is a sameness to the participants in neuroethics discussions with a few experts and commercial interests deciding on how the rest of us (however you define ‘us’ as per Gregor Wolbring’s essay) will live.

This paucity of perspectives is something I was getting at in my COVID-19 editorial for the Canadian Science Policy Centre. My thesis being that we need a range of ideas and insights that cannot be culled from small groups of people who’ve trained and read the same materials or entrepreneurs who too often seem to put profit over thoughtful implementations of new technologies. (See the PDF May 2020 edition [you’ll find me under Policy Development]) or see my May 15, 2020 posting here (with all the sources listed.)

As for this new research at Stanford, it’s exciting news, which raises questions, as it offers the hope of independent movement for people diagnosed as tetraplegic (sometimes known as quadriplegic.)

Nanoparticles and the gut health of major living species of animals

A July 27, 2020 news item on Nanowerk announces research into gut health described as seminal (Note: A link has been removed),

An international team of scientists has completed the first ever study into the potential impact of naturally occurring and man-made nanoparticles on the health of all types of the major living species of animals.

Conceived by researchers at the University of Plymouth, as part of the EU [European Union] Nanofase project, the study assessed how the guts of species from honey bees to humans could protect against the bioaccumulation and toxicological effects of engineered nanomaterials (ENMs) found within the environment.

A July 27, 2020 University of Plymouth press release, which originated the news item, provides more detail,

It showed that the digestive systems of many species have evolved to act as a barrier guarding against the absorption of potentially damaging particles.

However, invertebrates such as earthworms also have roving cells within their guts, which can take up ENMs and transfer them to the gut wall.

This represents an additional risk for many invertebrate species where the particles can be absorbed via these roving cells, with consequent effects on internal organs having the potential to cause lasting damage.

Fortunately, this process is not replicated in humans and other vertebrate animals, however there is still the potential for nanomaterials to have a negative impact through the food chain.

The study, published in the July [2020] edition of Environmental Science: Nano, involved scientists from the UK, the Netherlands, Slovenia and Portugal and focused on particles measuring up to 100 nanometres (around 1/10 millionth of a metre).

It combined existing and new research into species including insects and other invertebrates, fish, birds, and mammals, as well as identifying knowledge gaps on reptiles and amphibians. The study provides the first comprehensive overview of how differences in gut structure can affect the impact of ENMs across the animal kingdom.

Richard Handy, Professor of Environmental Toxicology at the University of Plymouth and the study’s senior author, said:

“This is a seminal piece work that combines nearly 100 years of zoology research with our current understanding of nanotechnology.

“The threats posed by engineered nanomaterials are becoming better known, but this study provides the first comprehensive and species-level assessment of how they might pose current and future threats. It should set the foundations for understanding the dietary hazard in the animal kingdom.”

Nanomaterials come in three forms – naturally occurring, incidentally occurring from human activities, and deliberately manufactured – and their use has increased exponentially in the last decade.

They have consistently found new applications in a wide variety of industrial sectors, including electrical appliances, medicines, cleaning products and textiles.

Professor Handy, who has advised organisations including the Organisation for Economic Co-operation and Development and the United States National Nanotechnology Initiative, added:

“Nanoparticles are far too small for the human eye to see but that doesn’t mean they cannot cause harm to living species. The review element of this study has shown they have actually been written about for many decades, but it is only recently that we have begun to understand the various ways they occur and now the extent to which they can be taken up. Our new EU project, NanoHarmony, looks to build on that knowledge and we are currently working with Public Health England and others to expand our method for detecting nanomaterials in tissues for food safety and other public health matters.”

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

The gut barrier and the fate of engineered nanomaterials: a view from comparative physiology by Meike van der Zande, Anita Jemec Kokalj, David J. Spurgeon, Susana Loureiro, Patrícia V. Silva, Zahra Khodaparast, Damjana Drobne, Nathaniel J. Clark, Nico W. van den Brink, Marta Baccaro, Cornelis A. M. van Gestel, Hans Bouwmeester and Richard D. Handy. Environmental Science: Nano, Issue 7 (July 2020) DOI: 10.1039/D0EN00174K First published 27 Apr 2020

This article is open access.

If you’re curious about Nanofase (Nanomaterial FAte and Speciation in the Environment), there’s more here and there’s more about NanoHarmony here.