Category Archives: risk

Gene editing and personalized medicine: Canada

Back in the fall of 2018 I came across one of those overexcited pieces about personalized medicine and gene editing tha are out there. This one came from an unexpected source, an author who is a “PhD Scientist in Medical Science (Blood and Vasculature” (from Rick Gierczak’s LinkedIn profile).

It starts our promisingly enough although I’m beginning to dread the use of the word ‘precise’ where medicine is concerned, (from a September 17, 2018 posting on the Science Borealis blog by Rick Gierczak (Note: Links have been removed),

CRISPR-Cas9 technology was accidentally discovered in the 1980s when scientists were researching how bacteria defend themselves against viral infection. While studying bacterial DNA called clustered regularly interspaced short palindromic repeats (CRISPR), they identified additional CRISPR-associated (Cas) protein molecules. Together, CRISPR and one of those protein molecules, termed Cas9, can locate and cut precise regions of bacterial DNA. By 2012, researchers understood that the technology could be modified and used more generally to edit the DNA of any plant or animal. In 2015, the American Association for the Advancement of Science chose CRISPR-Cas9 as science’s “Breakthrough of the Year”.

Today, CRISPR-Cas9 is a powerful and precise gene-editing tool [emphasis mine] made of two molecules: a protein that cuts DNA (Cas9) and a custom-made length of RNA that works like a GPS for locating the exact spot that needs to be edited (CRISPR). Once inside the target cell nucleus, these two molecules begin editing the DNA. After the desired changes are made, they use a repair mechanism to stitch the new DNA into place. Cas9 never changes, but the CRISPR molecule must be tailored for each new target — a relatively easy process in the lab. However, it’s not perfect, and occasionally the wrong DNA is altered [emphasis mine].

Note that Gierczak makes a point of mentioning that CRISPR/Cas9 is “not perfect.” And then, he gets excited (Note: Links have been removed),

CRISPR-Cas9 has the potential to treat serious human diseases, many of which are caused by a single “letter” mutation in the genetic code (A, C, T, or G) that could be corrected by precise editing. [emphasis mine] Some companies are taking notice of the technology. A case in point is CRISPR Therapeutics, which recently developed a treatment for sickle cell disease, a blood disorder that causes a decrease in oxygen transport in the body. The therapy targets a special gene called fetal hemoglobin that’s switched off a few months after birth. Treatment involves removing stem cells from the patient’s bone marrow and editing the gene to turn it back on using CRISPR-Cas9. These new stem cells are returned to the patient ready to produce normal red blood cells. In this case, the risk of error is eliminated because the new cells are screened for the correct edit before use.

The breakthroughs shown by companies like CRISPR Therapeutics are evidence that personalized medicine has arrived. [emphasis mine] However, these discoveries will require government regulatory approval from the countries where the treatment is going to be used. In the US, the Food and Drug Administration (FDA) has developed new regulations allowing somatic (i.e., non-germ) cell editing and clinical trials to proceed. [emphasis mine]

The potential treatment for sickle cell disease is exciting but Gierczak offers no evidence that this treatment or any unnamed others constitute proof that “personalized medicine has arrived.” In fact, Goldman Sachs, a US-based investment bank, makes the case that it never will .

Cost/benefit analysis

Edward Abrahams, president of the Personalized Medicine Coalition (US-based), advocates for personalized medicine while noting in passing, market forces as represented by Goldman Sachs in his May 23, 2018 piece for statnews.com (Note: A link has been removed),

…

One of every four new drugs approved by the Food and Drug Administration over the last four years was designed to become a personalized (or “targeted”) therapy that zeros in on the subset of patients likely to respond positively to it. That’s a sea change from the way drugs were developed and marketed 10 years ago.

Some of these new treatments have extraordinarily high list prices. But focusing solely on the cost of these therapies rather than on the value they provide threatens the future of personalized medicine.

…

… most policymakers are not asking the right questions about the benefits of these treatments for patients and society. Influenced by cost concerns, they assume that prices for personalized tests and treatments cannot be justified even if they make the health system more efficient and effective by delivering superior, longer-lasting clinical outcomes and increasing the percentage of patients who benefit from prescribed treatments.

Goldman Sachs, for example, issued a report titled “The Genome Revolution.” It argues that while “genome medicine” offers “tremendous value for patients and society,” curing patients may not be “a sustainable business model.” [emphasis mine] The analysis underlines that the health system is not set up to reap the benefits of new scientific discoveries and technologies. Just as we are on the precipice of an era in which gene therapies, gene-editing, and immunotherapies promise to address the root causes of disease, Goldman Sachs says that these therapies have a “very different outlook with regard to recurring revenue versus chronic therapies.”

…

Let’s just chew on this one (contemplate) for a minute”curing patients may not be ‘sustainable business model’!”

Coming down to earth: policy

While I find Gierczak to be over-enthused, he, like Abrahams, emphasizes the importance of new policy, in his case, the focus is Canadian policy. From Gierczak’s September 17, 2018 posting (Note: Links have been removed),

In Canada, companies need approval from Health Canada. But a 2004 law called the Assisted Human Reproduction Act (AHR Act) states that it’s a criminal offence “to alter the genome of a human cell, or in vitroembryo, that is capable of being transmitted to descendants”. The Actis so broadly written that Canadian scientists are prohibited from using the CRISPR-Cas9 technology on even somatic cells. Today, Canada is one of the few countries in the world where treating a disease with CRISPR-Cas9 is a crime.

On the other hand, some countries provide little regulatory oversight for editing either germ or somatic cells. In China, a company often only needs to satisfy the requirements of the local hospital where the treatment is being performed. And, if germ-cell editing goes wrong, there is little recourse for the future generations affected.

The AHR Act was introduced to regulate the use of reproductive technologies like in vitrofertilization and research related to cloning human embryos during the 1980s and 1990s. Today, we live in a time when medical science, and its role in Canadian society, is rapidly changing. CRISPR-Cas9 is a powerful tool, and there are aspects of the technology that aren’t well understood and could potentially put patients at risk if we move ahead too quickly. But the potential benefits are significant. Updated legislation that acknowledges both the risks and current realities of genomic engineering [emphasis mine] would relieve the current obstacles and support a path toward the introduction of safe new therapies.

…

Criminal ban on human gene-editing of inheritable cells (in Canada)

I had no idea there was a criminal ban on the practice until reading this January 2017 editorial by Bartha Maria Knoppers, Rosario Isasi, Timothy Caulfield, Erika Kleiderman, Patrick Bedford, Judy Illes, Ubaka Ogbogu, Vardit Ravitsky, & Michael Rudnicki for (Nature) npj Regenerative Medicine (Note: Links have been removed),

Driven by the rapid evolution of gene editing technologies, international policy is examining which regulatory models can address the ensuing scientific, socio-ethical and legal challenges for regenerative and personalised medicine.1 Emerging gene editing technologies, including the CRISPR/Cas9 2015 scientific breakthrough,2 are powerful, relatively inexpensive, accurate, and broadly accessible research tools.3 Moreover, they are being utilised throughout the world in a wide range of research initiatives with a clear eye on potential clinical applications. Considering the implications of human gene editing for selection, modification and enhancement, it is time to re-examine policy in Canada relevant to these important advances in the history of medicine and science, and the legislative and regulatory frameworks that govern them. Given the potential human reproductive applications of these technologies, careful consideration of these possibilities, as well as ethical and regulatory scrutiny must be a priority.4

With the advent of human embryonic stem cell research in 1978, the birth of Dolly (the cloned sheep) in 1996 and the Raelian cloning hoax in 2003, the environment surrounding the enactment of Canada’s 2004 Assisted Human Reproduction Act (AHRA) was the result of a decade of polarised debate,5 fuelled by dystopian and utopian visions for future applications. Rightly or not, this led to the AHRA prohibition on a wide range of activities, including the creation of embryos (s. 5(1)(b)) or chimeras (s. 5(1)(i)) for research and in vitro and in vivo germ line alterations (s. 5(1)(f)). Sanctions range from a fine (up to $500,000) to imprisonment (up to 10 years) (s. 60 AHRA).

In Canada, the criminal ban on gene editing appears clear, the Act states that “No person shall knowingly […] alter the genome of a cell of a human being or in vitro embryo such that the alteration is capable of being transmitted to descendants;” [emphases mine] (s. 5(1)(f) AHRA). This approach is not shared worldwide as other countries such as the United Kingdom, take a more regulatory approach to gene editing research.1 Indeed, as noted by the Law Reform Commission of Canada in 1982, criminal law should be ‘an instrument of last resort’ used solely for “conduct which is culpable, seriously harmful, and generally conceived of as deserving of punishment”.6 A criminal ban is a suboptimal policy tool for science as it is inflexible, stifles public debate, and hinders responsiveness to the evolving nature of science and societal attitudes.7 In contrast, a moratorium such as the self-imposed research moratorium on human germ line editing called for by scientists in December 20158 can at least allow for a time limited pause. But like bans, they may offer the illusion of finality and safety while halting research required to move forward and validate innovation.

On October 1st, 2016, Health Canada issued a Notice of Intent to develop regulations under the AHRA but this effort is limited to safety and payment issues (i.e. gamete donation). Today, there is a need for Canada to revisit the laws and policies that address the ethical, legal and social implications of human gene editing. The goal of such a critical move in Canada’s scientific and legal history would be a discussion of the right of Canadians to benefit from the advancement of science and its applications as promulgated in article 27 of the Universal Declaration of Human Rights9 and article 15(b) of the International Covenant on Economic, Social and Cultural Rights,10 which Canada has signed and ratified. Such an approach would further ensure the freedom of scientific endeavour both as a principle of a liberal democracy and as a social good, while allowing Canada to be engaged with the international scientific community.

…

Even though it’s a bit old, I still recommend reading the open access editorial in full, if you have the time.

One last thing abut the paper, the acknowledgements,

Sponsored by Canada’s Stem Cell Network, the Centre of Genomics and Policy of McGill University convened a ‘think tank’ on the future of human gene editing in Canada with legal and ethics experts as well as representatives and observers from government in Ottawa (August 31, 2016). The experts were Patrick Bedford, Janetta Bijl, Timothy Caulfield, Judy Illes, Rosario Isasi, Jonathan Kimmelman, Erika Kleiderman, Bartha Maria Knoppers, Eric Meslin, Cate Murray, Ubaka Ogbogu, Vardit Ravitsky, Michael Rudnicki, Stephen Strauss, Philip Welford, and Susan Zimmerman. The observers were Geneviève Dubois-Flynn, Danika Goosney, Peter Monette, Kyle Norrie, and Anthony Ridgway.

Competing interests

The authors declare no competing interests.

Both McGill and the Stem Cell Network pop up again. A November 8, 2017 article about the need for new Canadian gene-editing policies by Tom Blackwell for the National Post features some familiar names (Did someone have a budget for public relations and promotion?),

It’s one of the most exciting, and controversial, areas of health science today: new technology that can alter the genetic content of cells, potentially preventing inherited disease — or creating genetically enhanced humans.

But Canada is among the few countries in the world where working with the CRISPR gene-editing system on cells whose DNA can be passed down to future generations is a criminal offence, with penalties of up to 10 years in jail.

This week, one major science group announced it wants that changed, calling on the federal government to lift the prohibition and allow researchers to alter the genome of inheritable “germ” cells and embryos.

The potential of the technology is huge and the theoretical risks like eugenics or cloning are overplayed, argued a panel of the Stem Cell Network.

The step would be a “game-changer,” said Bartha Knoppers, a health-policy expert at McGill University, in a presentation to the annual Till & McCulloch Meetings of stem-cell and regenerative-medicine researchers [These meetings were originally known as the Stem Cell Network’s Annual General Meeting {AGM}]. [emphases mine]

…

“I’m completely against any modification of the human genome,” said the unidentified meeting attendee. “If you open this door, you won’t ever be able to close it again.”

If the ban is kept in place, however, Canadian scientists will fall further behind colleagues in other countries, say the experts behind the statement say; they argue possible abuses can be prevented with good ethical oversight.

“It’s a human-reproduction law, it was never meant to ban and slow down and restrict research,” said Vardit Ravitsky, a University of Montreal bioethicist who was part of the panel. “It’s a sort of historical accident … and now our hands are tied.”

…

There are fears, as well, that CRISPR could be used to create improved humans who are genetically programmed to have certain facial or other features, or that the editing could have harmful side effects. Regardless, none of it is happening in Canada, good or bad.

…

In fact, the Stem Cell Network panel is arguably skirting around the most contentious applications of the technology. It says it is asking the government merely to legalize research for its own sake on embryos and germ cells — those in eggs and sperm — not genetic editing of embryos used to actually get women pregnant.

The highlighted portions in the last two paragraphs of the excerpt were written one year prior to the claims by a Chinese scientist that he had run a clinical trial resulting in gene-edited twins, Lulu and Nana. (See my my November 28, 2018 posting for a comprehensive overview of the original furor). I have yet to publish a followup posting featuring the news that the CRISPR twins may have been ‘improved’ more extensively than originally realized. The initial reports about the twins focused on an illness-related reason (making them HIV ‘immune’) but made no mention of enhanced cognitive skills a side effect of eliminating the gene that would make them HIV ‘immune’. To date, the researcher has not made the bulk of his data available for an in-depth analysis to support his claim that he successfully gene-edited the twins. As well, there were apparently seven other pregnancies coming to term as part of the researcher’s clinical trial and there has been no news about those births.

Risk analysis innovation

Before moving onto the innovation of risk analysis, I want to focus a little more on at least one of the risks that gene-editing might present. Gierczak noted that CRISPR/Cas9 is “not perfect,” which acknowledges the truth but doesn’t convey all that much information.

While the terms ‘precision’ and ‘scissors’ are used frequently when describing the CRISPR technique, scientists actually mean that the technique is significantly ‘more precise’ than other techniques but they are not referencing an engineering level of precision. As for the ‘scissors’, it’s an analogy scientists like to use but in fact CRISPR is not as efficient and precise as a pair of scissors.

Michael Le Page in a July 16, 2018 article for New Scientist lays out some of the issues (Note: A link has been removed),

A study of CRIPSR suggests we shouldn’t rush into trying out CRISPR genome editing inside people’s bodies just yet. The technique can cause big deletions or rearrangements of DNA [emphasis mine], says Allan Bradley of the Wellcome Sanger Institute in the UK, meaning some therapies based on CRISPR may not be quite as safe as we thought.

The CRISPR genome editing technique is revolutionising biology, enabling us to create new varieties of plants and animals and develop treatments for a wide range of diseases.

The CRISPR Cas9 protein works by cutting the DNA of a cell in a specific place. When the cell repairs the damage, a few DNA letters get changed at this spot – an effect that can be exploited to disable genes.

At least, that’s how it is supposed to work. But in studies of mice and human cells, Bradley’s team has found that in around a fifth of cells, CRISPR causes deletions or rearrangements more than 100 DNA letters long. These surprising changes are sometimes thousands of letters long.

…

“I do believe the findings are robust,” says Gaetan Burgio of the Australian National University, an expert on CRISPR who has debunked previous studies questioning the method’s safety. “This is a well-performed study and fairly significant.”

…

I covered the Bradley paper and the concerns in a July 17, 2018 posting ‘The CRISPR ((clustered regularly interspaced short palindromic repeats)-CAS9 gene-editing technique may cause new genetic damage kerfuffle‘. (The ‘kerfufle’ was in reference to a report that the CRISPR market was affected by the publication of Bradley’s paper.)

Despite Health Canada not moving swiftly enough for some researchers, they have nonetheless managed to release an ‘outcome’ report about a consultation/analysis started in October 2016. Before getting to the consultation’s outcome, it’s interesting to look at how the consultation’s call for response was described (from Health Canada’s Toward a strengthened Assisted Human Reproduction Act ; A Consultation with Canadians on Key Policy Proposals webpage),

In October 2016, recognizing the need to strengthen the regulatory framework governing assisted human reproduction in Canada, Health Canada announced its intention to bring into force the dormant sections of the Assisted Human Reproduction Act and to develop the necessary supporting regulations.

This consultation document provides an overview of the key policy proposals that will help inform the development of regulations to support bringing into force Section 10, Section 12 and Sections 45-58 of the Act. Specifically, the policy proposals describe the Department’s position on the following:

Section 10: Safety of Donor Sperm and Ova

Scope and application

Regulated parties and their regulatory obligations

Processing requirements, including donor suitability assessment

Record-keeping and traceability

Section 12: Reimbursement

Expenditures that may be reimbursed

Process for reimbursement

Creation and maintenance of records

Sections 45-58: Administration and Enforcement

Scope of the administration and enforcement framework

Role of inspectors designated under the Act

The purpose of the document is to provide Canadians with an opportunity to review the policy proposals and to provide feedback [emphasis mine] prior to the Department finalizing policy decisions and developing the regulations. In addition to requesting stakeholders’ general feedback on the policy proposals, the Department is also seeking input on specific questions, which are included throughout the document.

It took me a while to find the relevant section (in particular, take note of ‘Federal Regulatory Oversight’),

3.2. AHR in Canada Today

Today, an increasing number of Canadians are turning to AHR technologies to grow or build their families. A 2012 Canadian study^Footnote 1 found that infertility is on the rise in Canada, with roughly 16% of heterosexual couples experiencing infertility. In addition to rising infertility, the trend of delaying marriage and parenthood, scientific advances in cryopreserving ova, and the increasing use of AHR by LGBTQ2 couples and single parents to build a family are all contributing to an increase in the use of AHR technologies.

The growing use of reproductive technologies by Canadians to help build their families underscores the need to strengthen the AHR Act. While the approach to regulating AHR varies from country to country, Health Canada has considered international best practices and the need for regulatory alignment when developing the proposed policies set out in this document. …

3.2.1 Federal Regulatory Oversight

Although the scope of the AHR Act was significantly reduced in 2012 and some of the remaining sections have not yet been brought into force, there are many important sections of the Act that are currently administered and enforced by Health Canada, as summarized generally below:

…

Section 5: Prohibited Scientific and Research Procedures
Section 5 prohibits certain types of scientific research and clinical procedures that are deemed unacceptable, including: human cloning, the creation of an embryo for non-reproductive purposes, maintaining an embryo outside the human body beyond the fourteenth day, sex selection for non-medical reasons, altering the genome in a way that could be transmitted to descendants, and creating a chimera or a hybrid. [emphasis mine]

….

It almost seems as if the they were hiding the section that broached the human gene-editing question. It doesn’t seem to have worked as it appears, there are some very motivated parties determined to reframe the discussion. Health Canada’s ‘outocme’ report, published March 2019, What we heard: A summary of scanning and consultations on what’s next for health product regulation reflects the success of those efforts,

1.0 Introduction and Context

Scientific and technological advances are accelerating the pace of innovation. These advances are increasingly leading to the development of health products that are better able to predict, define, treat, and even cure human diseases. Globally, many factors are driving regulators to think about how to enable health innovation. To this end, Health Canada has been expanding beyond existing partnerships and engaging both domestically and internationally. This expanding landscape of products and services comes with a range of new challenges and opportunities.

In keeping up to date with emerging technologies and working collaboratively through strategic partnerships, Health Canada seeks to position itself as a regulator at the forefront of health innovation. Following the targeted sectoral review of the Health and Biosciences Sector Regulatory Review consultation by the Treasury Board Secretariat, Health Canada held a number of targeted meetings with a broad range of stakeholders.

This report outlines the methodologies used to look ahead at the emerging health technology environment, [emphasis mine] the potential areas of focus that resulted, and the key findings from consultations.

…

… the Department identified the following key drivers that are expected to shape the future of health innovation:

The use of “big data” to inform decision-making: Health systems are generating more data, and becoming reliant on this data. The increasing accuracy, types, and volume of data available in real time enable automation and machine learning that can forecast activity, behaviour, or trends to support decision-making.

Greater demand for citizen agency: Canadians increasingly want and have access to more information, resources, options, and platforms to manage their own health (e.g., mobile apps, direct-to-consumer services, decentralization of care).

Increased precision and personalization in health care delivery: Diagnostic tools and therapies are increasingly able to target individual patients with customized therapies (e.g., individual gene therapy).

Increased product complexity: Increasingly complex products do not fit well within conventional product classifications and standards (e.g., 3D printing).

Evolving methods for production and distribution: In some cases, manufacturers and supply chains are becoming more distributed, challenging the current framework governing production and distribution of health products.

The ways in which evidence is collected and used are changing: The processes around new drug innovation, research and development, and designing clinical trials are evolving in ways that are more flexible and adaptive.

With these key drivers in mind, the Department selected the following six emerging technologies for further investigation to better understand how the health product space is evolving:

Artificial intelligence, including activities such as machine learning, neural networks, natural language processing, and robotics.

Advanced cell therapies, such as individualized cell therapies tailor-made to address specific patient needs.

Big data, from sources such as sensors, genetic information, and social media that are increasingly used to inform patient and health care practitioner decisions.

3D printing of health products (e.g., implants, prosthetics, cells, tissues).

New ways of delivering drugs that bring together different product lines and methods (e.g., nano-carriers, implantable devices).

Gene editing, including individualized gene therapies that can assist in preventing and treating certain diseases.

Next, to test the drivers identified and further investigate emerging technologies, the Department consulted key organizations and thought leaders across the country with expertise in health innovation. To this end, Health Canada held seven workshops with over 140 representatives from industry associations, small-to-medium sized enterprises and start-ups, larger multinational companies, investors, researchers, and clinicians in Ottawa, Toronto, Montreal, and Vancouver. [emphases mine]

…

The ‘outocme’ report, ‘What we heard …’, is well worth reading in its entirety; it’s about 9 pp.

I have one comment, ‘stakeholders’ don’t seem to include anyone who isn’t “from industry associations, small-to-medium sized enterprises and start-ups, larger multinational companies, investors, researchers, and clinician” or from “Ottawa, Toronto, Montreal, and Vancouver.” Aren’t the rest of us stakeholders?

Innovating risk analysis

This line in the report caught my eye (from Health Canada’s Toward a strengthened Assisted Human Reproduction Act ; A Consultation with Canadians on Key Policy Proposals webpage),

There is increasing need to enable innovation in a flexible, risk-based way, with appropriate oversight to ensure safety, quality, and efficacy. [emphases mine]

It reminded me of the 2019 federal budget (from my March 22, 2019 posting). One comment before proceeding, regulation and risk are tightly linked and, so, by innovating regulation they are by exttension alos innovating risk analysis,

… Budget 2019 introduces the first three “Regulatory Roadmaps” to specifically address stakeholder issues and irritants in these sectors, informed by over 140 responses [emphasis mine] from businesses and Canadians across the country, as well as recommendations from the Economic Strategy Tables.

Introducing Regulatory Roadmaps

These Roadmaps lay out the Government’s plans to modernize regulatory frameworks, without compromising our strong health, safety, and environmental protections. They contain proposals for legislative and regulatory amendments as well as novel regulatory approaches to accommodate emerging technologies, including the use of regulatory sandboxes and pilot projects—better aligning our regulatory frameworks with industry realities.

Budget 2019 proposes the necessary funding and legislative revisions so that regulatory departments and agencies can move forward on the Roadmaps, including providing the Canadian Food Inspection Agency, Health Canada and Transport Canada with up to $219.1 million over five years, starting in 2019–20, (with $0.5 million in remaining amortization), and $3.1 million per year on an ongoing basis.

In the coming weeks, the Government will be releasing the full Regulatory Roadmaps for each of the reviews, as well as timelines for enacting specific initiatives, which can be grouped in the following three main areas:

What Is a Regulatory Sandbox? Regulatory sandboxes are controlled “safe spaces” in which innovative products, services, business models and delivery mechanisms can be tested without immediately being subject to all of the regulatory requirements.
– European Banking Authority, 2017

…

Establishing a regulatory sandbox for new and innovative medical products
The regulatory approval system has not kept up with new medical technologies and processes. Health Canada proposes to modernize regulations to put in place a regulatory sandbox for new and innovative products, such as tissues developed through 3D printing, artificial intelligence, and gene therapies targeted to specific individuals. [emphasis mine]

Modernizing the regulation of clinical trials
Industry and academics have expressed concerns that regulations related to clinical trials are overly prescriptive and inconsistent. Health Canada proposes to implement a risk-based approach [emphasis mine] to clinical trials to reduce costs to industry and academics by removing unnecessary requirements for low-risk drugs and trials. The regulations will also provide the agri-food industry with the ability to carry out clinical trials within Canada on products such as food for special dietary use and novel foods.

Does the government always get 140 responses from a consultation process? Moving on, I agree with finding new approaches to regulatory processes and oversight and, by extension, new approaches to risk analysis.

Earlier in this post, I asked if someone had a budget for public relations/promotion. I wasn’t joking. My March 22, 2019 posting also included these line items in the proposed 2019 budget,

Budget 2019 proposes to make additional investments in support of the following organizations:
Stem Cell Network: Stem cell research—pioneered by two Canadians in the 1960s [James Till and Ernest McCulloch]—holds great promise for new therapies and medical treatments for respiratory and heart diseases, spinal cord injury, cancer, and many other diseases and disorders. The Stem Cell Network is a national not-for-profit organization that helps translate stem cell research into clinical applications and commercial products. To support this important work and foster Canada’s leadership in stem cell research, Budget 2019 proposes to provide the Stem Cell Network with renewed funding of $18 million over three years, starting in 2019–20.
…
Genome Canada: The insights derived from genomics—the study of the entire genetic information of living things encoded in their DNA and related molecules and proteins—hold the potential for breakthroughs that can improve the lives of Canadians and drive innovation and economic growth. Genome Canada is a not-for-profit organization dedicated to advancing genomics science and technology in order to create economic and social benefits for Canadians. To support Genome Canada’s operations, Budget 2019 proposes to provide Genome Canada with $100.5 million over five years, starting in 2020–21. This investment will also enable Genome Canada to launch new large-scale research competitions and projects, in collaboration with external partners, ensuring that Canada’s research community continues to have access to the resources needed to make transformative scientific breakthroughs and translate these discoveries into real-world applications.
…

Years ago, I managed to find a webpage with all of the proposals various organizations were submitting to a government budget committee. It was eye-opening. You can tell which organizations were able to hire someone who knew the current government buzzwords and the things that a government bureaucrat would want to hear and the organizations that didn’t.

Of course, if the government of the day is adamantly against or uninterested, no amount of persusasion will work to get your organization more money in the budget.

Finally

Reluctantly, I am inclined to explore the topic of emerging technologies such as gene-editing not only in the field of agriculture (for gene-editing of plants, fish, and animals see my November 28, 2018 posting) but also with humans. At the very least, it needs to be discussed whether we choose to participate or not.

If you are interested in the arguments against changing Canada’s prohibition against gene-editing of humans, there’s an Ocotber 2, 2017 posting on Impact Ethics by Françoise Baylis, Professor and Canada Research Chair in Bioethics and Philosophy at Dalhousie University, and Alana Cattapan, Johnson Shoyama Graduate School of Public Policy at the University of Saskatchewan, which makes some compelling arguments. Of course, it was written before the CRISPR twins (my November 28, 2018 posting).

Recaliing CRISPR Therapeutics (mentioned by Gierczak), the company received permission to run clinical trials in the US in October 2018 after the FDA (US Food and Drug Administration) lifted an earlier ban on their trials according to an Oct. 10, 2018 article by Frank Vinhuan for exome,

…

The partners also noted that their therapy is making progress outside of the U.S. They announced that they have received regulatory clearance in “multiple countries” to begin tests of the experimental treatment in both sickle cell disease and beta thalassemia, …

It seems to me that the quotes around “multiple countries” are meant to suggest doubt of some kind. Generally speaking, company representatives make those kinds of generalizations when they’re trying to pump up their copy. E.g., 50% increase in attendance but no whole numbers to tell you what that means. It could mean two people attended the first year and then brought a friend the next year or 100 people attended and the next year there were 150.

Despite attempts to declare personalized medicine as having arrived, I think everything is still in flux with no preordained outcome. The future has yet to be determined but it will be and I , for one, would like to have some say in the matter.

Gold nanoparticles not always always biologically stable

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Gold nanoparticle biodissolution by a freshwater macrophyte and its associated microbiome by Astrid Avellan, Marie Simonin, Eric McGivney, Nathan Bossa, Eleanor Spielman-Sun, Jennifer D. Rocca, Emily S. Bernhardt, Nicholas K. Geitner, Jason M. Unrine, Mark R. Wiesner, & Gregory V. Lowry. Nature Nanotechnology (2018) DOI: https://doi.org/10.1038/s41565-018-0231-y Published 13 August 2018

This paper is behind a paywall.

Nanoparticles in combination could be more toxic

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It seems that one set of nanoparticles, e.g., silver nanoparticles, in combination with another material, e.g., cadmium ions, are more dangerous than either one separately according to an August 17, 2018 University of Southern Denmark press release by Birgitte Svennevig (also on EurekAlert but dated August 20, 2018),

Researchers warn that a combination of nanoparticles and contaminants may form a cocktail that is harmful to our cells. In their study, 72 pct. of cells died after exposure to a cocktail of nano-silver and cadmium ions.

Nanoparticles are becoming increasingly widespread in our environment. Thousands of products contain nanoparticles because of their unique properties. Silver nanoparticles are one example: They have an effective antibacterial effect and can be found in refrigerators, sports clothes, cosmetics, tooth brushes, water filters, etc.

…

There is a significant difference between how the cells react when exposed to nanosilver alone and when they are exposed to a cocktail of nanosilver and cadmium ions. Cadmium ions are naturally found everywhere around us on Earth.

In the study, 72 pct. of the cells died, when exposed to both nanosilver and cadmiun ions. When exposed to nanosilver only, 25 pct. died. When exposed to cadmium ions only, 12 pct. died.

The study was conducted on human liver cancer cells.

This study indicates, that we should not look at nanoparticles isolated when we investigate and discuss the effects, they may have on our health. We need to take cocktail effects into account, said Professor Frank Kjeldsen, Dept of Biochemistry and Molecular Biology, SDU, adding:

Products with nano particles are being developed and manufactured every day, but in most countries there are no regulations, so there is no way of knowing what and how many nanoparticles are being released into the environment. In my opinion, this should be stopped.

Other studies, led by Professor Kjeldsen have previously shown that human cells interact with metal nanoparticles.

One study showed that nano-silver leads to the formation free radicals in cells and changes in the form and amount of proteins. Many serious diseases are characterized by an overproduction of free radicals in cells. This applies to cancer and neurological diseases such as Alzheimer’s and Parkinson’s.

This is not great news but there are a few things to note about this research. First, it was conducted on cells and therefore not subject to some of the defensive systems found in complete biological organisms such as a mouse or a dandelion plant for example.

Also, since they were cancer cells one might suspect their reactions might differ from those of healthy cells. As for how the cells were exposed to the contaminants, I think (???) they were sitting in a solution of contaminants and most of us do not live in that kind of environment.. Finally, with regard to the concentrations, I have no idea if they are greater than one might expect to encounter in one’s lifecycle but it’s always worth questioning just how much exposure you might expect during yours or a mouse’s or a dandelion’s life.

These caveats aside, Professor Frank Kjeldsen’s work raises some very concerning issues and his work adds to a growing body of evidence.

Here’s a video featuring Dr. Kjeldsen talking about his work,

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

Co-exposure to silver nanoparticles and cadmium induce metabolic adaptation in HepG2 cells by Renata Rank Miranda, Vladimir Gorshkov, Barbara Korzeniowska, Stefan J. Kempf, Francisco Filipak Neto, & Frank Kjeldsen. Nanotoxicology DOI: https://doi.org/10.1080/17435390.2018.1489987 Published online: 11 Jul 2018

This paper is open access.

It’s a very ‘carbony’ time: graphene jacket, graphene-skinned airplane, and schwarzite

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In August 2018, I been stumbled across several stories about graphene-based products and a new form of carbon.

Graphene jacket

The company producing this jacket has as its goal “… creating bionic clothing that is both bulletproof and intelligent.” Well, ‘bionic‘ means biologically-inspired engineering and ‘intelligent‘ usually means there’s some kind of computing capability in the product. This jacket, which is the first step towards the company’s goal, is not bionic, bulletproof, or intelligent. Nonetheless, it represents a very interesting science experiment in which you, the consumer, are part of step two in the company’s R&D (research and development).

Onto Vollebak’s graphene jacket,

Courtesy: Vollebak

From an August 14, 2018 article by Jesus Diaz for Fast Company,

Graphene is the thinnest possible form of graphite, which you can find in your everyday pencil. It’s purely bi-dimensional, a single layer of carbon atoms that has unbelievable properties that have long threatened to revolutionize everything from aerospace engineering to medicine. …

Despite its immense promise, graphene still hasn’t found much use in consumer products, thanks to the fact that it’s hard to manipulate and manufacture in industrial quantities. The process of developing Vollebak’s jacket, according to the company’s cofounders, brothers Steve and Nick Tidball, took years of intensive research, during which the company worked with the same material scientists who built Michael Phelps’ 2008 Olympic Speedo swimsuit (which was famously banned for shattering records at the event).

…

The jacket is made out of a two-sided material, which the company invented during the extensive R&D process. The graphene side looks gunmetal gray, while the flipside appears matte black. To create it, the scientists turned raw graphite into something called graphene “nanoplatelets,” which are stacks of graphene that were then blended with polyurethane to create a membrane. That, in turn, is bonded to nylon to form the other side of the material, which Vollebak says alters the properties of the nylon itself. “Adding graphene to the nylon fundamentally changes its mechanical and chemical properties–a nylon fabric that couldn’t naturally conduct heat or energy, for instance, now can,” the company claims.

The company says that it’s reversible so you can enjoy graphene’s properties in different ways as the material interacts with either your skin or the world around you. “As physicists at the Max Planck Institute revealed, graphene challenges the fundamental laws of heat conduction, which means your jacket will not only conduct the heat from your body around itself to equalize your skin temperature and increase it, but the jacket can also theoretically store an unlimited amount of heat, which means it can work like a radiator,” Tidball explains.

He means it literally. You can leave the jacket out in the sun, or on another source of warmth, as it absorbs heat. Then, the company explains on its website, “If you then turn it inside out and wear the graphene next to your skin, it acts like a radiator, retaining its heat and spreading it around your body. The effect can be visibly demonstrated by placing your hand on the fabric, taking it away and then shooting the jacket with a thermal imaging camera. The heat of the handprint stays long after the hand has left.”

…

There’s a lot more to the article although it does feature some hype and I’m not sure I believe Diaz’s claim (August 14, 2018 article) that ‘graphene-based’ hair dye is perfectly safe ( Note: A link has been removed),

Graphene is the thinnest possible form of graphite, which you can find in your everyday pencil. It’s purely bi-dimensional, a single layer of carbon atoms that has unbelievable properties that will one day revolutionize everything from aerospace engineering to medicine. Its diverse uses are seemingly endless: It can stop a bullet if you add enough layers. It can change the color of your hair with no adverse effects. [emphasis mine] It can turn the walls of your home into a giant fire detector. “It’s so strong and so stretchy that the fibers of a spider web coated in graphene could catch a falling plane,” as Vollebak puts it in its marketing materials.

Not unless things have changed greatly since March 2018. My August 2, 2018 posting featured the graphene-based hair dye announcement from March 2018 and a cautionary note from Dr. Andrew Maynard (scroll down ab out 50% of the way for a longer excerpt of Maynard’s comments),

Northwestern University’s press release proudly announced, “Graphene finds new application as nontoxic, anti-static hair dye.” The announcement spawned headlines like “Enough with the toxic hair dyes. We could use graphene instead,” and “’Miracle material’ graphene used to create the ultimate hair dye.”

From these headlines, you might be forgiven for getting the idea that the safety of graphene-based hair dyes is a done deal. Yet having studied the potential health and environmental impacts of engineered nanomaterials for more years than I care to remember, I find such overly optimistic pronouncements worrying – especially when they’re not backed up by clear evidence.

…

These studies need to be approached with care, as the precise risks of graphene exposure will depend on how the material is used, how exposure occurs and how much of it is encountered. Yet there’s sufficient evidence to suggest that this substance should be used with caution – especially where there’s a high chance of exposure or that it could be released into the environment.

…

The full text of Dr. Maynard’s comments about graphene hair dyes and risk can be found here.

Bearing in mind that graphene-based hair dye is an entirely different class of product from the jacket, I wouldn’t necessarily dismiss risks; I would like to know what kind of risk assessment and safety testing has been done. Due to their understandable enthusiasm, the brothers Tidball have focused all their marketing on the benefits and the opportunity for the consumer to test their product (from graphene jacket product webpage),

While it’s completely invisible and only a single atom thick, graphene is the lightest, strongest, most conductive material ever discovered, and has the same potential to change life on Earth as stone, bronze and iron once did. But it remains difficult to work with, extremely expensive to produce at scale, and lives mostly in pioneering research labs. So following in the footsteps of the scientists who discovered it through their own highly speculative experiments, we’re releasing graphene-coated jackets into the world as experimental prototypes. Our aim is to open up our R&D and accelerate discovery by getting graphene out of the lab and into the field so that we can harness the collective power of early adopters as a test group. No-one yet knows the true limits of what graphene can do, so the first edition of the Graphene Jacket is fully reversible with one side coated in graphene and the other side not. If you’d like to take part in the next stage of this supermaterial’s history, the experiment is now open. You can now buy it, test it and tell us about it. [emphasis mine]

…

How maverick experiments won the Nobel Prize

While graphene’s existence was first theorised in the 1940s, it wasn’t until 2004 that two maverick scientists, Andre Geim and Konstantin Novoselov, were able to isolate and test it. Through highly speculative and unfunded experimentation known as their ‘Friday night experiments,’ they peeled layer after layer off a shaving of graphite using Scotch tape until they produced a sample of graphene just one atom thick. After similarly leftfield thinking won Geim the 2000 Ig Nobel prize for levitating frogs using magnets, the pair won the Nobel prize in 2010 for the isolation of graphene.

…

Should you be interested, in beta-testing the jacket, it will cost you $695 (presumably USD); order here. One last thing, Vollebak is based in the UK.

Graphene skinned plane

An August 14, 2018 news item (also published as an August 1, 2018 Haydale press release) by Sue Keighley on Azonano heralds a new technology for airplans,

Haydale, (AIM: HAYD), the global advanced materials group, notes the announcement made yesterday from the University of Central Lancashire (UCLAN) about the recent unveiling of the world’s first graphene skinned plane at the internationally renowned Farnborough air show.

The prepreg material, developed by Haydale, has potential value for fuselage and wing surfaces in larger scale aero and space applications especially for the rapidly expanding drone market and, in the longer term, the commercial aerospace sector. By incorporating functionalised nanoparticles into epoxy resins, the electrical conductivity of fibre-reinforced composites has been significantly improved for lightning-strike protection, thereby achieving substantial weight saving and removing some manufacturing complexities.

Before getting to the photo, here’s a definition for pre-preg from its Wikipedia entry (Note: Links have been removed),

Pre-preg is “pre-impregnated” composite fibers where a thermoset polymer matrix material, such as epoxy, or a thermoplastic resin is already present. The fibers often take the form of a weave and the matrix is used to bond them together and to other components during manufacture.

Haydale has supplied graphene enhanced prepreg material for Juno, a three-metre wide graphene-enhanced composite skinned aircraft, that was revealed as part of the ‘Futures Day’ at Farnborough Air Show 2018. [downloaded from https://www.azonano.com/news.aspx?newsID=36298]

A July 31, 2018 University of Central Lancashire (UCLan) press release provides a tiny bit more (pun intended) detail,

The University of Central Lancashire (UCLan) has unveiled the world’s first graphene skinned plane at an internationally renowned air show.

Juno, a three-and-a-half-metre wide graphene skinned aircraft, was revealed on the North West Aerospace Alliance (NWAA) stand as part of the ‘Futures Day’ at Farnborough Air Show 2018.

The University’s aerospace engineering team has worked in partnership with the Sheffield Advanced Manufacturing Research Centre (AMRC), the University of Manchester’s National Graphene Institute (NGI), Haydale Graphene Industries (Haydale) and a range of other businesses to develop the unmanned aerial vehicle (UAV), which also includes graphene batteries and 3D printed parts.

Billy Beggs, UCLan’s Engineering Innovation Manager, said: “The industry reaction to Juno at Farnborough was superb with many positive comments about the work we’re doing. Having Juno at one the world’s biggest air shows demonstrates the great strides we’re making in leading a programme to accelerate the uptake of graphene and other nano-materials into industry.

“The programme supports the objectives of the UK Industrial Strategy and the University’s Engineering Innovation Centre (EIC) to increase industry relevant research and applications linked to key local specialisms. Given that Lancashire represents the fourth largest aerospace cluster in the world, there is perhaps no better place to be developing next generation technologies for the UK aerospace industry.”

Previous graphene developments at UCLan have included the world’s first flight of a graphene skinned wing and the launch of a specially designed graphene-enhanced capsule into near space using high altitude balloons.

UCLan engineering students have been involved in the hands-on project, helping build Juno on the Preston Campus.

Haydale supplied much of the material and all the graphene used in the aircraft. Ray Gibbs, Chief Executive Officer, said: “We are delighted to be part of the project team. Juno has highlighted the capability and benefit of using graphene to meet key issues faced by the market, such as reducing weight to increase range and payload, defeating lightning strike and protecting aircraft skins against ice build-up.”

David Bailey Chief Executive of the North West Aerospace Alliance added: “The North West aerospace cluster contributes over £7 billion to the UK economy, accounting for one quarter of the UK aerospace turnover. It is essential that the sector continues to develop next generation technologies so that it can help the UK retain its competitive advantage. It has been a pleasure to support the Engineering Innovation Centre team at the University in developing the world’s first full graphene skinned aircraft.”

The Juno project team represents the latest phase in a long-term strategic partnership between the University and a range of organisations. The partnership is expected to go from strength to strength following the opening of the £32m EIC facility in February 2019.

The next step is to fly Juno and conduct further tests over the next two months.

Next item, a new carbon material.

Schwarzite

I love watching this gif of a schwarzite,

The three-dimensional cage structure of a schwarzite that was formed inside the pores of a zeolite. (Graphics by Yongjin Lee and Efrem Braun)

An August 13, 2018 news item on Nanowerk announces the new carbon structure,

The discovery of buckyballs [also known as fullerenes, C60, or buckminsterfullerenes] surprised and delighted chemists in the 1980s, nanotubes jazzed physicists in the 1990s, and graphene charged up materials scientists in the 2000s, but one nanoscale carbon structure – a negatively curved surface called a schwarzite – has eluded everyone. Until now.

University of California, Berkeley [UC Berkeley], chemists have proved that three carbon structures recently created by scientists in South Korea and Japan are in fact the long-sought schwarzites, which researchers predict will have unique electrical and storage properties like those now being discovered in buckminsterfullerenes (buckyballs or fullerenes for short), nanotubes and graphene.

An August 13, 2018 UC Berkeley news release by Robert Sanders, which originated the news item, describes how the Berkeley scientists and the members of their international collaboration from Germany, Switzerland, Russia, and Italy, have contributed to the current state of schwarzite research,

The new structures were built inside the pores of zeolites, crystalline forms of silicon dioxide – sand – more commonly used as water softeners in laundry detergents and to catalytically crack petroleum into gasoline. Called zeolite-templated carbons (ZTC), the structures were being investigated for possible interesting properties, though the creators were unaware of their identity as schwarzites, which theoretical chemists have worked on for decades.

Based on this theoretical work, chemists predict that schwarzites will have unique electronic, magnetic and optical properties that would make them useful as supercapacitors, battery electrodes and catalysts, and with large internal spaces ideal for gas storage and separation.

UC Berkeley postdoctoral fellow Efrem Braun and his colleagues identified these ZTC materials as schwarzites based of their negative curvature, and developed a way to predict which zeolites can be used to make schwarzites and which can’t.

“We now have the recipe for how to make these structures, which is important because, if we can make them, we can explore their behavior, which we are working hard to do now,” said Berend Smit, an adjunct professor of chemical and biomolecular engineering at UC Berkeley and an expert on porous materials such as zeolites and metal-organic frameworks.

Smit, the paper’s corresponding author, Braun and their colleagues in Switzerland, China, Germany, Italy and Russia will report their discovery this week in the journal Proceedings of the National Academy of Sciences. Smit is also a faculty scientist at Lawrence Berkeley National Laboratory.

Playing with carbon

Diamond and graphite are well-known three-dimensional crystalline arrangements of pure carbon, but carbon atoms can also form two-dimensional “crystals” — hexagonal arrangements patterned like chicken wire. Graphene is one such arrangement: a flat sheet of carbon atoms that is not only the strongest material on Earth, but also has a high electrical conductivity that makes it a promising component of electronic devices.

The cage structure of a schwarzite that was formed inside the pores of a zeolite. The zeolite is subsequently dissolved to release the new material. (Graphics by Yongjin Lee and Efrem Braun)

Graphene sheets can be wadded up to form soccer ball-shaped fullerenes – spherical carbon cages that can store molecules and are being used today to deliver drugs and genes into the body. Rolling graphene into a cylinder yields fullerenes called nanotubes, which are being explored today as highly conductive wires in electronics and storage vessels for gases like hydrogen and carbon dioxide. All of these are submicroscopic, 10,000 times smaller than the width of a human hair.

To date, however, only positively curved fullerenes and graphene, which has zero curvature, have been synthesized, feats rewarded by Nobel Prizes in 1996 and 2010, respectively.

In the 1880s, German physicist Hermann Schwarz investigated negatively curved structures that resemble soap-bubble surfaces, and when theoretical work on carbon cage molecules ramped up in the 1990s, Schwarz’s name became attached to the hypothetical negatively curved carbon sheets.

“The experimental validation of schwarzites thus completes the triumvirate of possible curvatures to graphene; positively curved, flat, and now negatively curved,” Braun added.

Minimize me

Like soap bubbles on wire frames, schwarzites are topologically minimal surfaces. When made inside a zeolite, a vapor of carbon-containing molecules is injected, allowing the carbon to assemble into a two-dimensional graphene-like sheet lining the walls of the pores in the zeolite. The surface is stretched tautly to minimize its area, which makes all the surfaces curve negatively, like a saddle. The zeolite is then dissolved, leaving behind the schwarzite.

A computer-rendered negatively curved soap bubble that exhibits the geometry of a carbon schwarzite. (Felix Knöppel image)

“These negatively-curved carbons have been very hard to synthesize on their own, but it turns out that you can grow the carbon film catalytically at the surface of a zeolite,” Braun said. “But the schwarzites synthesized to date have been made by choosing zeolite templates through trial and error. We provide very simple instructions you can follow to rationally make schwarzites and we show that, by choosing the right zeolite, you can tune schwarzites to optimize the properties you want.”

Researchers should be able to pack unusually large amounts of electrical charge into schwarzites, which would make them better capacitors than conventional ones used today in electronics. Their large interior volume would also allow storage of atoms and molecules, which is also being explored with fullerenes and nanotubes. And their large surface area, equivalent to the surface areas of the zeolites they’re grown in, could make them as versatile as zeolites for catalyzing reactions in the petroleum and natural gas industries.

Braun modeled ZTC structures computationally using the known structures of zeolites, and worked with topological mathematician Senja Barthel of the École Polytechnique Fédérale de Lausanne in Sion, Switzerland, to determine which of the minimal surfaces the structures resembled.

The team determined that, of the approximately 200 zeolites created to date, only 15 can be used as a template to make schwarzites, and only three of them have been used to date to produce schwarzite ZTCs. Over a million zeolite structures have been predicted, however, so there could be many more possible schwarzite carbon structures made using the zeolite-templating method.

Other co-authors of the paper are Yongjin Lee, Seyed Mohamad Moosavi and Barthel of the École Polytechnique Fédérale de Lausanne, Rocio Mercado of UC Berkeley, Igor Baburin of the Technische Universität Dresden in Germany and Davide Proserpio of the Università degli Studi di Milano in Italy and Samara State Technical University in Russia.

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

Generating carbon schwarzites via zeolite-templating by Efrem Braun, Yongjin Lee, Seyed Mohamad Moosavi, Senja Barthel, Rocio Mercado, Igor A. Baburin, Davide M. Proserpio, and Berend Smit. PNAS August 14, 2018. 201805062; published ahead of print August 14, 2018. https://doi.org/10.1073/pnas.1805062115

This paper appears to be open access.

Observing individual silver nanoparticles in real time

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A new technique for better understanding how silver nanoparticles might affect the environment was announced in a July 30, 2018 news item on ScienceDaily,

Chemists at Ruhr-Universität Bochum have developed a new method of observing the chemical reactions of individual silver nanoparticles, which only measure a thousandth of the thickness of a human hair, in real time. The particles are used in medicine, food and sports items because they have an antibacterial and anti-inflammatory effect. However, how they react and degrade in ecological and biological systems is so far barely understood. The team in the Research Group for Electrochemistry and Nanoscale Materials showed that the nanoparticles transform into poorly soluble silver chloride particles under certain conditions. The group led by Prof Dr Kristina Tschulik reports on the results in the Journal of the American Chemical Society from July 11, 2018.

A July 30,2018 Ruhr-University Bochum (RUB) press release (also on EurekAlert) by Julia Weiler, which originated the news item, provides more information,

Even under well-defined laboratory conditions, current research has yielded different, sometimes contradictory, results on the reaction of silver nanoparticles. “In every batch of nanoparticles, the individual properties of the particles, such as size and shape, vary,” says Kristina Tschulik, a member of the Cluster of Excellence Ruhr Explores Solvation. “With previous procedures, a myriad of particles was generally investigated at the same time, meaning that the effects of these variations could not be recorded. Or the measurements took place in a high vacuum, not under natural conditions in an aqueous solution.”

The team led by Kristina Tschulik thus developed a method that enables individual silver particles to be investigated in a natural environment. “Our aim is to be able to record the reactivity of individual particles,” explains the researcher. This requires a combination of electrochemical and spectroscopic methods. With optical and hyperspectral dark-field microscopy, the group was able to observe individual nanoparticles as visible and coloured pixels. Using the change in the colour of the pixels, or more precisely their spectral information, the researchers were able to follow what was happening in an electrochemical experiment in real time.

Degradation of the particles slowed down

In the experiment, the team replicated the oxidation of silver in the presence of chloride ions, which often takes place in ecological and biological systems. “Until now, it was generally assumed that the silver particles dissolve in the form of silver ions,” describes Kristina Tschulik. However, poorly soluble silver chloride was formed in the experiment – even if only a few chloride ions were present in the solution.

“This extends the lifespan of the nanoparticles to an extreme extent and their breakdown is slowed down in an unexpectedly drastic manner,” summarises Tschulik. “This is equally important for bodies of water and for living beings because this mechanism could cause the heavy metal silver to accumulate locally, which can be toxic for many organisms.”

Further development planned

The Bochum-based group now wants to further improve its technology for analysing individual nanoparticles in order to better understand the ageing mechanisms of such particles. The researchers thus want to obtain more information about the biocompatibility of the silver particles and the lifespan and ageing of catalytically active nanoparticles in the future.

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

Simultaneous Opto- and Spectro-Electrochemistry: Reactions of Individual Nanoparticles Uncovered by Dark-Field Microscopy by Kevin Wonner, Mathies V. Evers, and Kristina Tschulik. J. Am. Chem. Soc., Article ASAP DOI: 10.1021/jacs.8b02367 Publication Date (Web): July 11, 2018

Copyright © 2018 American Chemical Society

This paper is behind a paywall.

Algae outbreaks (dead zones) in wetlands and waterways

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It’s been over seven years since I first started writing about Duke University’s Center for the Environmental Implications of Nanotechnology and mesocosms (miniature ecosystems) and the impact that nanoparticles may have on plants and water (see August 11, 2011 posting). Since then, their focus has shifted from silver nanoparticles and their impact on plants, fish, bacteria, etc. to a more general examination of metallic nanoparticles and water. A June 25, 2018 news item on ScienceDaily announces some of their latest work,

The last 10 years have seen a surge in the use of tiny substances called nanomaterials in agrochemicals like pesticides and fungicides. The idea is to provide more disease protection and better yields for crops, while decreasing the amount of toxins sprayed on agricultural fields.

But when combined with nutrient runoff from fertilized cropland and manure-filled pastures, these “nanopesticides” could also mean more toxic algae outbreaks for nearby streams, lakes and wetlands, a new study finds.

A June 25, 2018 Duke University news release (also on EurekAlert) by Robin A. Smith, which originated the news item, provides more detail,

Too small to see with all but the most powerful microscopes, engineered nanomaterials are substances manufactured to be less than 100 nanometers in diameter, many times smaller than a hair’s breadth.

Their nano-scale gives them different chemical and physical properties from their bulk counterparts, including more surface area for reactions and interactions.

Those interactions could intensify harmful algal blooms in wetlands, according to experiments led by Marie Simonin, a postdoctoral associate with biology professor Emily Bernhardt at Duke University.

Carbon nanotubes and teeny tiny particles of silver, titanium dioxide and other metals are already added to hundreds of commercial products to make everything from faster, lighter electronics, self-cleaning fabrics, and smarter food packaging that can monitor food for spoilage. They are also used on farms for slow- or controlled-release plant fertilizers and pesticides and more targeted delivery, and because they are effective at lower doses than conventional products.

These and other applications have generated tremendous interest and investment in nanomaterials. However the potential risks to human health or the environment aren’t fully understood, Simonin said.

Most of the 260,000 to 309,000 metric tons of nanomaterials produced worldwide each year are eventually disposed in landfills, according to a previous study. But of the remainder, up to 80,400 metric tons per year are released into soils, and up to 29,200 metric tons end up in natural bodies of water.

“And these emerging contaminants don’t end up in water bodies alone,” Simonin said. “They probably co-occur with nutrient runoff. There are likely multiple stressors interacting.”

Algae outbreaks already plague polluted waters worldwide, said Steven Anderson, a research analyst in the Bernhardt Lab at Duke and one of the authors of the research.

Nitrogen and phosphorous pollution makes its way into wetlands and waterways in the form of agricultural runoff and untreated wastewater. The excessive nutrients cause algae to grow out of control, creating a thick mat of green scum or slime on the surface of the water that blocks sunlight from reaching other plants.

These nutrient-fueled “blooms” eventually reduce oxygen levels to the point where fish and other organisms can’t survive, creating dead zones in the water. Some algal blooms also release toxins that can make pets and people who swallow them sick.

To find out how the combined effects of nutrient runoff and nanoparticle contamination would affect this process, called eutrophication, the researchers set up 18 separate 250-liter tanks with sandy sloped bottoms to mimic small wetlands.

Each open-air tank was filled with water, soil and a variety of wetland plants and animals such as waterweed and mosquitofish.

Over the course of the nine-month experiment, some tanks got a weekly dose of algae-promoting nitrates and phosphates like those found in fertilizers, some tanks got nanoparticles — either copper or gold — and some tanks got both.

Along the way the researchers monitored water chemistry, plant and algae growth and metabolism, and nanoparticle accumulation in plant tissues.

“The results were surprising,” Simonin said. The nanoparticles had tiny effects individually, but when added together with nutrients, even low concentrations of gold and copper nanoparticles used in fungicides and other products turned the once-clear water a murky pea soup color, its surface covered with bright green smelly mats of floating algae.

Over the course of the experiment, big algal blooms were more than three times more frequent and more persistent in tanks where nanoparticles and nutrients were added together than where nutrients were added alone. The algae overgrowths also reduced dissolved oxygen in the water.

It’s not clear yet how nanoparticle exposure shifts the delicate balance between plants and algae as they compete for nutrients and other resources. But the results suggest that nanoparticles and other “metal-based synthetic chemicals may be playing an under-appreciated role in the global trends of increasing eutrophication,” the researchers said.

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

Engineered nanoparticles interact with nutrients to intensify eutrophication in a wetland ecosystem experiment by Marie Simonin, Benjamin P. Colman, Steven M. Anderson, Ryan S. King, Matthew T. Ruis, Astrid Avellan, Christina M. Bergemann, Brittany G. Perrotta, Nicholas K. Geitner, Mengchi Ho, Belen de la Barrera, Jason M. Unrine, Gregory V. Lowry, Curtis J. Richardson, Mark R. Wiesner, Emily S. Bernhardt. Ecological Applications, 2018; DOI: 10.1002/eap.1742 First published: 25 June 2018

This paper is behind a paywall.

Australian scientists say that sunscreens with zinc oxide nanoparticles aren’t toxic to you

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The Australians have had quite the struggle over whether or not to use nanotechnology-enabled sunscreens (see my Feb. 9, 2012 posting about an Australian nanosunscreen debacle and I believe the reverberations continue even ’til today). This latest research will hopefully help calm the waters. From a Dec. 4, 2018 news item on ScienceDaily,

Zinc oxide (ZnO) has long been recognized as an effective sunscreen agent. However, there have been calls for sunscreens containing ZnO nanoparticles to be banned because of potential toxicity and the need for caution in the absence of safety data in humans. An important new study provides the first direct evidence that intact ZnO nanoparticles neither penetrate the human skin barrier nor cause cellular toxicity after repeated application to human volunteers under in-use conditions. This confirms that the known benefits of using ZnO nanoparticles in sunscreens clearly outweigh the perceived risks, reports the Journal of Investigative Dermatology.

A December 4, 2018 Elsevier (Publishing) press release (also on EurekAlert), which originated the news item, provides international context for the safety discussion while providing more details about this latest research,

The safety of nanoparticles used in sunscreens has been a highly controversial international issue in recent years, as previous animal exposure studies found much higher skin absorption of zinc from application of ZnO sunscreens to the skin than in human studies. Some public advocacy groups have voiced concern that penetration of the upper layer of the skin by sunscreens containing ZnO nanoparticles could gain access to the living cells in the viable epidermis with toxic consequences, including DNA damage. A potential danger, therefore, is that this concern may also result in an undesirable downturn in sunscreen use. A 2017 National Sun Protection Survey by the Cancer Council Australia found only 55 percent of Australians believed it was safe to use sunscreen every day, down from 61 per cent in 2014.

Investigators in Australia studied the safety of repeated application of agglomerated ZnO nanoparticles applied to five human volunteers (aged 20 to 30 years) over five days. This mimics normal product use by consumers. They applied ZnO nanoparticles suspended in a commercial sunscreen base to the skin of volunteers hourly for six hours and daily for five days. Using multiphoton tomography with fluorescence lifetime imaging microscopy, they showed that the nanoparticles remained within the superficial layers of the stratum corneum and in the skin furrows. The fate of ZnO nanoparticles was also characterized in excised human skin in vitro. They did not penetrate the viable epidermis and no cellular toxicity was seen, even after repeated hourly or daily applications typically used for sunscreens.

“The terrible consequences of skin cancer and photoaging are much greater than any toxicity risk posed by approved sunscreens,” stated lead investigator Michael S. Roberts, PhD, of the Therapeutics Research Centre, The University of Queensland Diamantina Institute, Translational Research Institute, Brisbane, and School of Pharmacy and Medical Sciences, University of South Australia, Sansom Institute, Adelaide, QLD, Australia.

“This study has shown that sunscreens containing nano ZnO can be repeatedly applied to the skin with minimal risk of any toxicity. We hope that these findings will help improve consumer confidence in these products, and in turn lead to better sun protection and reduction in ultraviolet-induced skin aging and cancer cases,” he concluded.

“This study reinforces the important public health message that the known benefits of using ZnO nano sunscreens clearly outweigh the perceived risks of using nano sunscreens that are not supported by the scientific evidence,” commented Paul F.A. Wright, PhD, School of Health and Biomedical Sciences, RMIT University, Bundoora, VIC, Australia, in an accompanying editorial. “Of great significance is the investigators’ finding that the slight increase in zinc ion concentrations in viable epidermis was not associated with cellular toxicity under conditions of realistic ZnO nano sunscreen use.

A November 21, 2018 University of South Australia press release (also on EurekAlert) provides some additional insight into the Australian situation,, Note: Links have been removed,

It’s safe to slap on the sunscreen this summer – in repeated doses – despite what you have read about the potential toxicity of sunscreens.

A new study led by the University of Queensland (UQ) and University of South Australia (UniSA) provides the first direct evidence that zinc oxide nanoparticles used in sunscreen neither penetrate the skin nor cause cellular toxicity after repeated applications.

The research, published this week in the Journal of Investigative Dermatology, refutes widespread claims among some public advocacy groups – and a growing belief among consumers – about the safety of nanoparticulate-based sunscreens.

UQ and UniSA lead investigator, Professor Michael Roberts, says the myth about sunscreen toxicity took hold after previous animal studies found much higher skin absorption of zinc-containing sunscreens than in human studies.

“There were concerns that these zinc oxide nanoparticles could be absorbed into the epidermis, with toxic consequences, including DNA damage,” Professor Roberts says.

The toxicity link was picked up by consumers, sparking fears that Australians could reduce their sunscreen use, echoed by a Cancer Council 2017 National Sun Protection Survey showing a drop in the number of people who believed it was safe to use sunscreens every day.

Professor Roberts and his co-researchers in Brisbane, Adelaide, Perth and Germany studied the safety of repeated applications of zinc oxide nanoparticles applied to five volunteers aged 20-30 years.

Volunteers applied the ZnO nanoparticles every hour for six hours on five consecutive days.

“Using superior imaging methods, we established that the nanoparticles remained within the superficial layers of the skin and did not cause any cellular damage,” Professor Roberts says.

“We hope that these findings help improve consumer confidence in these products and in turn lead to better sun protection. The terrible consequences of skin cancer and skin damage caused by prolonged sun exposure are much greater than any toxicity posed by approved sunscreens.”

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

Support for the Safe Use of Zinc Oxide Nanoparticle Sunscreens: Lack of Skin Penetration or Cellular Toxicity after Repeated Application in Volunteers by Yousuf H. Mohammed, Amy Holmes, Isha N. Haridass, Washington Y. Sanchez, Hauke Studier, Jeffrey E. Grice, Heather A.E. Benson, Michael S. Roberts. Jurnal of Investigative Dermatology. DOI: https://doi.org/10.1016/j.jid.2018.08.024 Article in Press Published online (Dec. 4, 2018?)

As of Dec. 11, 2018, this article is open access.

Canadian research into nanomaterial workplace exposure in the air and on surfaces

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An August 30, 2018 news item on Nanowerk announces the report,

The monitoring of air contamination by engineered nanomaterials (ENM) is a complex process with many uncertainties and limitations owing to the presence of particles of nanometric size that are not ENMs, the lack of validated instruments for breathing zone measurements and the many indicators to be considered.

In addition, some organizations, France’s Institut national de recherche et de sécurité (INRS) and Québec’s Institut de recherche Robert-Sauvé en santé et en sécurité du travail (IRSST) among them, stress the need to also sample surfaces for ENM deposits.

In other words, to get a better picture of the risks of worker exposure, we need to fine-tune the existing methods of sampling and characterizing ENMs and develop new one. Accordingly, the main goal of this project was to develop innovative methodological approaches for detailed qualitative as well as quantitative characterization of workplace exposure to ENMs.

A PDF of the 88-page report is available in English or in French.

An August 30, 2018 (?) abstract of the IRSST report titled An Assessment of Methods of Sampling and Characterizing Engineered Nanomaterials in the Air and on Surfaces in the Workplace (2nd edition) by Maximilien Debia, Gilles L’Espérance, Cyril Catto, Philippe Plamondon, André Dufresne, Claude Ostiguy, which originated the news item, outlines what you can expect from the report,

This research project has two complementary parts: a laboratory investigation and a fieldwork component. The laboratory investigation involved generating titanium dioxide (TiO₂) nanoparticles under controlled laboratory conditions and studying different sampling and analysis devices. The fieldwork comprised a series of nine interventions adapted to different workplaces and designed to test a variety of sampling devices and analytical procedures and to measure ENM exposure levels among Québec workers.

The methods for characterizing aerosols and surface deposits that were investigated include: i) measurement by direct-reading instruments (DRI), such as condensation particle counters (CPC), optical particle counters (OPC), laser photometers, aerodynamic diameter spectrometers and electric mobility spectrometer; ii) transmission electron microscopy (TEM) or scanning transmission electron microscopy (STEM) with a variety of sampling devices, including the Mini Particle Sampler® (MPS); iii) measurement of elemental carbon (EC); iv) inductively coupled plasma mass spectrometry (ICP-MS) and (v) Raman spectroscopy.

The workplace investigations covered a variety of industries (e.g., electronics, manufacturing, printing, construction, energy, research and development) and included producers as well as users or integrators of ENMs. In the workplaces investigated, we found nanometals or metal oxides (TiO₂, SiO₂, zinc oxides, lithium iron phosphate, titanate, copper oxides), nanoclays, nanocellulose and carbonaceous materials, including carbon nanofibers (CNF) and carbon nanotubes (CNT)—single-walled (SWCNT) as well as multiwalled (MWCNT).

The project helped to advance our knowledge of workplace assessments of ENMs by documenting specific tasks and industrial processes (e.g., printing and varnishing) as well as certain as yet little investigated ENMs (nanocellulose, for example).

Based on our investigations, we propose a strategy for more accurate assessment of ENM exposure using methods that require a minimum of preanalytical handling. The recommended strategy is a systematic two-step assessment of workplaces that produce and use ENMs. The first step involves testing with different DRIs (such as a CPC and a laser photometer) as well as sample collection and subsequent microscopic analysis (MPS + TEM/STEM) to clearly identify the work tasks that generate ENMs. The second step, once work exposure is confirmed, is specific quantification of the ENMs detected. The following findings are particularly helpful for detailed characterization of ENM exposure:

The first conclusive tests of a technique using ICP-MS to quantify the metal oxide content of samples collected in the workplace

The possibility of combining different sampling methods recommended by the National Institute for Occupational Safety and Health (NIOSH) to measure elemental carbon as an indicator of NTC/NFC, as well as demonstration of the limitation of this method stemming from observed interference with the black carbon particles required to synthesis carbon materials (for example, Raman spectroscopy showed that less than 6% of the particles deposited on the electron microscopy grid at one site were SWCNTs)

The clear advantages of using an MPS (instead of the standard 37-mm cassettes used as sampling media for electron microscopy), which allows quantification of materials

The major impact of sampling time: a long sampling time overloads electron microscopy grids and can lead to overestimation of average particle agglomerate size and underestimation of particle concentrations

The feasibility and utility of surface sampling, either with sampling pumps or passively by diffusion onto the electron microscopy grids, to assess ENM dispersion in the workplace

These original findings suggest promising avenues for assessing ENM exposure, while also showing their limitations. Improvements to our sampling and analysis methods give us a better understanding of ENM exposure and help in adapting and implementing control measures that can minimize occupational exposure.

You can download the full report in either or both English and French from the ‘Nanomaterials – A Guide to Good Practices Facilitating Risk Management in the Workplace, 2nd Edition‘ webpage.

Better hair dyes with graphene and a cautionary note

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Beauty products aren’t usually the first applications that come to mind when discussing graphene or any other research and development (R&D) as I learned when teaching a course a few years ago. But research and development in that field are imperative as every company is scrambling for a short-lived competitive advantage for a truly new products or a perceived competitive advantage in a field where a lot of products are pretty much the same.

This March 15, 2018 news item on ScienceDaily describes graphene as a potential hair dye,

Graphene, a naturally black material, could provide a new strategy for dyeing hair in difficult-to-create dark shades. And because it’s a conductive material, hair dyed with graphene might also be less prone to staticky flyaways. Now, researchers have put it to the test. In an article published March 15 [2018] in the journal Chem, they used sheets of graphene to make a dye that adheres to the surface of hair, forming a coating that is resistant to at least 30 washes without the need for chemicals that open up and damage the hair cuticle.

Courtesy: Northwestern University

A March 15, 2018 Cell Press news release on EurekAlert, which originated the news item, fills in more the of the story,

Most permanent hair dyes used today are harmful to hair. “Your hair is covered in these cuticle scales like the scales of a fish, and people have to use ammonia or organic amines to lift the scales and allow dye molecules to get inside a lot quicker,” says senior author Jiaxing Huang, a materials scientist at Northwestern University. But lifting the cuticle makes the strands of the hair more brittle, and the damage is only exacerbated by the hydrogen peroxide that is used to trigger the reaction that synthesizes the dye once the pigment molecules are inside the hair.

These problems could theoretically be solved by a dye that coats rather than penetrates the hair. “However, the obvious problem of coating-based dyes is that they tend to wash out very easily,” says Huang. But when he and his team coated samples of human hair with a solution of graphene sheets, they were able to turn platinum blond hair black and keep it that way for at least 30 washes–the number necessary for a hair dye to be considered “permanent.”

This effectiveness has to do with the structure of graphene: it’s made of up thin, flexible sheets that can adapt to uneven surfaces. “Imagine a piece of paper. A business card is very rigid and doesn’t flex by itself. But if you take a much bigger sheet of newspaper–if you still can find one nowadays–it can bend easily. This makes graphene sheets a good coating material,” he says. And once the coating is formed, the graphene sheets are particularly good at keeping out water during washes, which keeps the water from eroding both the graphene and the polymer binder that the team also added to the dye solution to help with adhesion.

The graphene dye has additional advantages. Each coated hair is like a little wire in that it is able to conduct heat and electricity. This means that it’s easy for graphene-dyed hair to dissipate static electricity, eliminating the problem of flyaways on dry winter days. The graphene flakes are large enough that they won’t absorb through the skin like other dye molecules. And although graphene is typically black, its precursor, graphene oxide, is light brown. But the color of graphene oxide can be gradually darkened with heat or chemical reactions, meaning that this dye could be used for a variety of shades or even for an ombre effect.

What Huang thinks is particularly striking about this application of graphene is that it takes advantage of graphene’s most obvious property. “In many potential graphene applications, the black color of graphene is somewhat undesirable and something of a sore point,” he says. Here, though, it’s applied to a field where creating dark colors has historically been a problem.

The graphene used for hair dye also doesn’t need to be of the same high quality as it does for other applications. “For hair dye, the most important property is graphene being black. You can have graphene that is too lousy for higher-end electronic applications, but it’s perfectly okay for this. So I think this application can leverage the current graphene product as is, and that’s why I think that this could happen a lot sooner than many of the other proposed applications,” he says.

Making it happen is his next goal. He hopes to get funding to continue the research and make these dyes a reality for the people whose lives they would improve. “This is an idea that was inspired by curiosity. It was very fun to do, but it didn’t sound very big and noble when we started working on it,” he says. “But after we deep-dived into studying hair dyes, we realized that, wow, this is actually not at all a small problem. And it’s one that graphene could really help to solve.”

Northwestern University’s Amanda Morris also wrote a March 15, 2018 news release (it’s repetitive but there are some interesting new details; Note: Links have been removed),

It’s an issue that has plagued the beauty industry for more than a century: Dying hair too often can irreparably damage your silky strands.

Now a Northwestern University team has used materials science to solve this age-old problem. The team has leveraged super material graphene to develop a new hair dye that is less harmful [emphasis mine], non-damaging and lasts through many washes without fading. Graphene’s conductive nature also opens up new opportunities for hair, such as turning it into in situ electrodes or integrating it with wearable electronic devices.

…

Dying hair might seem simple and ordinary, but it’s actually a sophisticated chemical process. Called the cuticle, the outermost layer of a hair is made of cells that overlap in a scale-like pattern. Commercial dyes work by using harsh chemicals, such as ammonia and bleach, to first pry open the cuticle scales to allow colorant molecules inside and then trigger a reaction inside the hair to produce more color. Not only does this process cause hair to become more fragile, some of the small molecules are also quite toxic.

Huang and his team bypassed harmful chemicals altogether by leveraging the natural geometry of graphene sheets. While current hair dyes use a cocktail of small molecules that work by chemically altering the hair, graphene sheets are soft and flexible, so they wrap around each hair for an even coat. Huang’s ink formula also incorporates edible, non-toxic polymer binders to ensure that the graphene sticks — and lasts through at least 30 washes, which is the commercial requirement for permanent hair dye. An added bonus: graphene is anti-static, so it keeps winter-weather flyaways to a minimum.

“It’s similar to the difference between a wet paper towel and a tennis ball,” Huang explained, comparing the geometry of graphene to that of other black pigment particles, such as carbon black or iron oxide, which can only be used in temporary hair dyes. “The paper towel is going to wrap and stick much better. The ball-like particles are much more easily removed with shampoo.”

This geometry also contributes to why graphene is a safer alternative. Whereas small molecules can easily be inhaled or pass through the skin barrier, graphene is too big to enter the body. “Compared to those small molecules used in current hair dyes, graphene flakes are humongous,” said Huang, who is a member of Northwestern’s International Institute of Nanotechnology.

Ever since graphene — the two-dimensional network of carbon atoms — burst onto the science scene in 2004, the possibilities for the promising material have seemed nearly endless. With its ultra-strong and lightweight structure, graphene has potential for many applications in high-performance electronics, high-strength materials and energy devices. But development of those applications often require graphene materials to be as structurally perfect as possible in order to achieve extraordinary electrical, mechanical or thermal properties.

The most important graphene property for Huang’s hair dye, however, is simply its color: black. So Huang’s team used graphene oxide, an imperfect version of graphene that is a cheaper, more available oxidized derivative.

“Our hair dye solves a real-world problem without relying on very high-quality graphene, which is not easy to make,” Huang said. “Obviously more work needs to be done, but I feel optimistic about this application.”

Still, future versions of the dye could someday potentially leverage graphene’s notable properties, including its highly conductive nature.

“People could apply this dye to make hair conductive on the surface,” Huang said. “It could then be integrated with wearable electronics or become a conductive probe. We are only limited by our imagination.”

So far, Huang has developed graphene-based hair dyes in multiple shades of brown and black. Next, he plans to experiment with more colors.

Interestingly, the tiny note of caution”less harmful” doesn’t appear in the Cell Press news release. Never fear, Dr. Andrew Maynard (Director Risk Innovation Lab at Arizona State University) has written a March 20, 2018 essay on The Conversation suggesting a little further investigation (Note: Links have been removed),

Northwestern University’s press release proudly announced, “Graphene finds new application as nontoxic, anti-static hair dye.” The announcement spawned headlines like “Enough with the toxic hair dyes. We could use graphene instead,” and “’Miracle material’ graphene used to create the ultimate hair dye.”

From these headlines, you might be forgiven for getting the idea that the safety of graphene-based hair dyes is a done deal. Yet having studied the potential health and environmental impacts of engineered nanomaterials for more years than I care to remember, I find such overly optimistic pronouncements worrying – especially when they’re not backed up by clear evidence.

Tiny materials, potentially bigger problems

Engineered nanomaterials like graphene and graphene oxide (the particular form used in the dye experiments) aren’t necessarily harmful. But nanomaterials can behave in unusual ways that depend on particle size, shape, chemistry and application. Because of this, researchers have long been cautious about giving them a clean bill of health without first testing them extensively. And while a large body of research to date doesn’t indicate graphene is particularly dangerous, neither does it suggest it’s completely safe.

A quick search of scientific papers over the past few years shows that, since 2004, over 2,000 studies have been published that mention graphene toxicity; nearly 500 were published in 2017 alone.

This growing body of research suggests that if graphene gets into your body or the environment in sufficient quantities, it could cause harm. A 2016 review, for instance, indicated that graphene oxide particles could result in lung damage at high doses (equivalent to around 0.7 grams of inhaled material). Another review published in 2017 suggested that these materials could affect the biology of some plants and algae, as well as invertebrates and vertebrates toward the lower end of the ecological pyramid. The authors of the 2017 study concluded that research “unequivocally confirms that graphene in any of its numerous forms and derivatives must be approached as a potentially hazardous material.”

These studies need to be approached with care, as the precise risks of graphene exposure will depend on how the material is used, how exposure occurs and how much of it is encountered. Yet there’s sufficient evidence to suggest that this substance should be used with caution – especially where there’s a high chance of exposure or that it could be released into the environment.

Unfortunately, graphene-based hair dyes tick both of these boxes. Used in this way, the substance is potentially inhalable (especially with spray-on products) and ingestible through careless use. It’s also almost guaranteed that excess graphene-containing dye will wash down the drain and into the environment.

…

Undermining other efforts?

I was alerted to just how counterproductive such headlines can be by my colleague Tim Harper, founder of G2O Water Technologies – a company that uses graphene oxide-coated membranes to treat wastewater. Like many companies in this area, G2O has been working to use graphene responsibly by minimizing the amount of graphene that ends up released to the environment.

Yet as Tim pointed out to me, if people are led to believe “that bunging a few grams of graphene down the drain every time you dye your hair is OK, this invalidates all the work we are doing making sure the few nanograms of graphene on our membranes stay put.” Many companies that use nanomaterials are trying to do the right thing, but it’s hard to justify the time and expense of being responsible when someone else’s more cavalier actions undercut your efforts.

…

Overpromising results and overlooking risk

This is where researchers and their institutions need to move beyond an “economy of promises” that spurs on hyperbole and discourages caution, and think more critically about how their statements may ultimately undermine responsible and beneficial development of a technology. They may even want to consider using guidelines, such as the Principles for Responsible Innovation developed by the organization Society Inside, for instance, to guide what they do and say.

…

If you have time, I encourage you to read Andrew’s piece in its entirety.

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

Multifunctional Graphene Hair Dye by Chong Luo, Lingye Zhou, Kevin Chiou, and Jiaxing Huang. Chem DOI: https://doi.org/10.1016/j.chempr.2018.02.02 Publication stage: In Press Corrected Proof

This paper appears to be open access.

*Two paragraphs (repetitions) were deleted from the excerpt of Dr. Andrew Maynard’s essay on August 14, 2018

Panning for silver nanoparticles in your clothes washer

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A March 20, 2018 news item on phys.org describes a new approach to treating wastewater (Note: Links have been removed),

Humans have known since ancient times that silver kills or stops the growth of many microorganisms. Hippocrates, the father of medicine, is said to have used silver preparations for treating ulcers and healing wounds. Until the introduction of antibiotics in the 1940s, colloidal silver (tiny particles suspended in a liquid) was a mainstay for treating burns, infected wounds and ulcers. Silver is still used today in wound dressings, in creams and as a coating on medical devices.

Since the 1990s, manufacturers have added silver nanoparticles to numerous consumer products to enhance their antibacterial and anti-odor properties. Examples include clothes, towels, undergarments, socks, toothpaste and soft toys. Nanoparticles are ultra-small particles, ranging from 1 to 100 nanometers in diameter – too small to see even with a microscope. According to a widely cited database, about one-fourth of nanomaterial-based consumer products currently marketed in the United States contain nanosilver.

Multiple studies have reported that nanosilver leaches out of textiles when they are laundered. Research also reveals that nanosilver may be toxic to humans and aquatic and marine organisms. Although it is widely used, little is understood about its fate or long-term toxic effects in the environment.

We are developing ways to convert this potential ecological crisis into an opportunity by recovering pure silver nanoparticles, which have many industrial applications, from laundry wastewater. In a recently published study, we describe a technique for silver recovery and discuss the key technical challenges. Our approach tackles this problem at the source – in this case, individual washing machines. We believe that this strategy has great promise for getting newly identified contaminants out of wastewater.

A March 20, 2018 essay by Sukalyan Sengupta, Professor of Wastewater Treatment, and Tabish Nawaz. Doctoral Student, both at University of Massachusetts at Dartmouth on The Conversation website, which originated the news item, expands on the theme (Note: Links have been removed),

Use of nanosilver in consumer products has steadily risen in the past decade. The market share of silver-based textiles rose from 9 percent in 2004 to 25 percent in 2011.

Several investigators have measured the silver content of textiles and found values ranging from 0.009 to 21,600 milligrams of silver per kilogram of textile. Studies show that the amount of silver leached in the wash solution depends on many factors, including interactions between detergent and other chemicals and how silver is attached to the textiles.

In humans, exposure to silver can harm liver cells, skin and lungs. Prolonged exposure or exposure to a large dose can cause a condition called Argyria, in which the victim’s skin turns permanently bluish-gray.

…

Once silver goes down the drain and ends up at wastewater treatment plants, it can potentially harm bacterial treatment processes, making them less efficient, and foul treatment equipment. More than 90 percent of silver nanoparticles released in wastewater end up in nutrient-rich biosolids left over at the end of sewage treatment, which often are used on land as agricultural fertilizers.

Silver is toxic in aquatic environments, a concern that’s becoming more serious with the increased use of silver nanoparticles and awareness that oceans, rivers, and lakes are dangerously stressed.

Sengupta and Nawaz go on to describe their proposed solution (Note: Links have been removed),

Our research shows that the most efficient way to remove silver from wastewater is by treating it in the washing machine. At this point silver concentrations are relatively high, and silver is initially released from treated clothing in a chemical form that is feasible to recover.

A bit of chemistry is helpful here. Our recovery method employs a widely used chemistry process called ion exchange. Ions are atoms or molecules that have an electrical charge. In ion exchange, a solid and a liquid are brought together and exchange ions with each other.

For example, household soaps do not lather well in “hard” water, which contains high levels of ions such as magnesium and calcium. Many home water filters use ion exchange to “soften” the water, replacing those materials with other ions that do not affect its properties in the same way.

For this process to work, the ions that switch places must both be either positively or negatively charged. Nanosilver is initially released from textiles as silver ion, which is a cation – an ion with a positive charge (hence the plus sign in its chemical symbol, Ag+).

Even at the source, removing silver from washwater is challenging. Silver concentrations in the wash solution are relatively low compared to other cations, such as calcium, that could interfere with the removal process. Detergent chemistry complicates the picture further because some detergent components can potentially interact with silver.

To recover silver without picking up other chemicals, the recovery process must use materials that have a chemical affinity for silver. In a previous study, we described a potential solution: Using ion-exchange materials embedded with sulfur-based chemicals, which bind preferentially with silver.

In our new study, we passed washwater through an ion-exchange resin column and analyzed how each major detergent ingredient interacted with silver in the water and affected the resin’s ability to remove silver from the water. By manipulating process conditions such as pH, temperature and concentration of nonsilver cations, we were able to identify conditions that maximized silver recovery.

We found that pH and the levels of calcium ions (Ca2+) were critical factors. Higher levels of hydrogen or calcium ions bind up detergent ingredients and prevent them from interacting with silver ions, so the ion-exchange resin can remove the silver from the solution. We also found that some detergent ingredients – particularly bleaching and water-softening agents – made the ion-exchange resin work less efficiently. Depending on these conditions, we recovered between 20 percent and 99 percent of the silver in the washwater.

The researchers go on to propose a new approach to treating wastewater (Note: A link has been removed),

Today wastewater is collected from multiple sources, such as homes and businesses, and piped over long distances to centralized wastewater treatment plants. But increasing evidence shows that these facilities are ill-equipped to keep newly identified contaminants out of the environment, since they use one common treatment scheme for many different waste streams.

We believe the future is in decentralized systems that can treat different types of wastewater with specific technologies designed specifically for the materials they contain. If wastewater from laundromats contains different contaminants than wastewater from restaurants, why treat them the same way?

Interesting, non? In any event, here’s a link to and a citation for what I believe is the researchers’ latest paper on this subject,

Silver Recovery from Laundry Washwater: The Role of Detergent Chemistry by Tabish Nawaz and Sukalyan Sengupta. ACS Sustainable Chem. Eng., 2018, 6 (1), pp 600–608 DOI: 10.1021/acssuschemeng.7b02933 Publication Date (Web): November 21, 2017

Copyright © 2017 American Chemical Society

This paper is behind a paywall. For anyone who can’t get access, Karla Lant provides a bit more technical detail about the work in her February 2, 2018 article for fondriest.com.

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Commentary about nanotech, science policy and communication, society, and the arts

Category Archives: risk

Gene editing and personalized medicine: Canada

Cost/benefit analysis

Coming down to earth: policy

Criminal ban on human gene-editing of inheritable cells (in Canada)

Competing interests

Risk analysis innovation

3.2. AHR in Canada Today

3.2.1 Federal Regulatory Oversight

1.0 Introduction and Context

Innovating risk analysis

Finally

Gold nanoparticles not always always biologically stable

Nanoparticles in combination could be more toxic

It’s a very ‘carbony’ time: graphene jacket, graphene-skinned airplane, and schwarzite

Graphene jacket

How maverick experiments won the Nobel Prize

Graphene skinned plane

Schwarzite

Playing with carbon

Minimize me

Observing individual silver nanoparticles in real time

Degradation of the particles slowed down

Further development planned

Algae outbreaks (dead zones) in wetlands and waterways

Australian scientists say that sunscreens with zinc oxide nanoparticles aren’t toxic to you

Canadian research into nanomaterial workplace exposure in the air and on surfaces

Better hair dyes with graphene and a cautionary note

Panning for silver nanoparticles in your clothes washer