Posts Tagged ‘nano titanium dioxide’

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Self-cleaning products dangerous?

Friday, June 14th, 2013

For anyone else out there who hates housecleaning, this is heartbreaking research. Personally, I’m not sure I can ever forgive Professor Jonathan Raff at Indian University for this (from a June 12, 2103 Indiana University news release; also on EurekAlert),

Research by Indiana University [IU] environmental scientists shows that air-pollution-removal technology used in “self-cleaning” paints and building surfaces may actually cause more problems than they solve.

The study finds that titanium dioxide coatings, seen as promising for their role in breaking down airborne pollutants on contact, are likely in real-world conditions to convert abundant ammonia to nitrogen oxide, the key precursor of harmful ozone pollution.

“As air quality standards become more stringent, people are going to be thinking about other technologies that can reduce pollution,” said Jonathan D. Raff, assistant professor in the School of Public and Environmental Affairs at IU Bloomington and an author of the study. “Our research suggests that this may not be one of them.”

Here’s a link to and a citation for this published study,

Photooxidation of Ammonia on TiO2 as a Source of NO and NO2 under Atmospheric Conditions by Mulu A. Kebede, Mychel E. Varner ‡, Nicole K. Scharko, R. Benny Gerber, and Jonathan D. Raff. J. Am. Chem. Soc., 2013, 135 (23), pp 8606–8615 DOI: 10.1021/ja401846x Publication Date (Web): May 30, 2013

Copyright © 2013 American Chemical Society

This research is behind a paywall.

The news release goes on to explain what makes this latest discovery about titanium dioxide particularly relevant,

The findings are timely because the Environmental Protection Agency is developing stricter regulations for ground-level ozone, a primary component in photochemical smog. The pollution is linked to serious health problems, including breathing difficulties and heart and lung disease.

Ozone is produced by reactions involving nitrogen oxides (NOx), which come primarily from motor vehicle emissions, and volatile organic compounds resulting from industrial processes. Equipping cars with catalytic converters has been effective at reducing ozone in urban areas. But different technologies may be needed to meet tighter air-quality standards of the future.

The need has sparked interest in titanium dioxide, a common mineral that is used as a whitening agent in paints and surface coatings. The compound acts as a photocatalyst, breaking down nitrogen oxides, ammonia and other pollutants in the presence of sunlight. “Self-cleaning” surfaces coated with titanium dioxide can break down chemical grime that will otherwise adhere to urban buildings. News stories have celebrated “smog-eating” tiles and concrete surfaces coated with the compound.

But Raff and his colleagues show that, in normal environmental conditions, titanium dioxide also catalyzes the incomplete breakdown of ammonia into nitrogen oxides. Ammonia is an abundant constituent in motor vehicle emissions, and its conversion to nitrogen oxides could result in increases in harmful ozone concentrations.

“We show that uptake of atmospheric NH3 (ammonia) onto surfaces containing TiO2 (titanium dioxide) is not a permanent removal process, as previously thought, but rather a photochemical route for generating reactive oxides of nitrogen that play a role in air pollution and are associated with significant health effects,” the authors write.

Raff, who is also an adjunct professor of chemistry in the IU College of Arts and Sciences, said other studies missed the effect on ammonia because they investigated reactions that occur with high levels of emissions under industrial conditions, not the low levels and actual humidity levels typically present in urban environments.

The findings also call into question other suggestions for using titanium dioxide for environmental remediation — for example, to remove odor-causing organic compounds from emissions produced by confined livestock feeding operations. Titanium dioxide has also been suggested as a geo-engineering substance that could be injected into the upper atmosphere to reflect sunlight away from the Earth and combat global warming.

Further studies in Raff’s lab are aimed at producing better understanding of the molecular processes involved when titanium dioxide catalyzes the breakdown of ammonia. The results could suggest approaches for developing more effective pollution-control equipment as well as improvements in industrial processes involving ammonia.

It’ll be interesting to see how that resolves itself. I imagine some of the civil society groups are going to get very excited about this research.

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NanoSustain published four case studies: zinc oxide, titanium dioxide, carbon nanotubes, and nanocellulose

Tuesday, May 21st, 2013

A May 17, 2013 news item on Nanowerk highlight a European Commission-funded project, NanoSustain and its publication of a fact sheet and four case studies,,

NanoSustain, a €2.5 million NMP small collaborative project (2010-2013) funded by the European Union under FP7, has published a fact sheet and four case studies addressing these issues.

How do nanotechnology-based products impact human health and the environment?
Can they be recycled?
Can they be safely disposed of?
How can you find out?

The March 20, 2013 NanoSustain news release, which originated the news item, goes on to explain,

… the EC-funded NanoSustain project has been developing new sustainable solutions through an investigation of the life-cycle of nanotechnology-based products, in particular the physical and chemical characteristics of materials, hazard and exposure aspects, and end-of-life disposal or recycling to determine the fate and impact of nanomaterials.

A summary of the different materials and products tested within NanoSustain:

• Case Study #1: Titanium dioxide for paints
• Case Study #2: Zinc oxide for glazing products
• Case Study #3: Carbon nanotubes epoxy resins for plastics
- for structural or electrical/antistatic applications
• Case Study #4: Nanocellulose for advanced paper applications

Information about the individual experimental approaches

Descriptions of the different techniques developed

How these techniques have been successfully applied in physical-chemical characterisation; life-cycle analysis; final disposal; recycling.

Getting access to the case case studies and the fact sheet requires filling out a form but once you’ve done that you get instant access to the materials.

Here’s some information from EuroSustain’s fact sheet,

Factsheets

Analytical Techniques

Development of sustainable solutions for nanotechnology-based products based on hazard characterization and LCA1 The primary goal of the NanoSustain project is to develop new technical solutions for the sustainable design and use, recycling and final treatment of selected nanotechnology-based products.

To achieve this the project has the following objectives: 1) to assess the hazard of selected nanomaterials based on a comprehensive data survey and generation concerning their physicochemical (PC) and toxicological properties, exposure probabilities, etc., and the adaptation, evaluation, validation and use of existing analytical, testing and life-cycle assessment (LCA) methods; 2) to assess the impact of selected products during their life cycle in relation to material and energy flows (LCA); 3) to assess possible exposure routes and risks associated with the handling of these materials, their transformation and final fate; and 4) to explore the feasibility and sustainability of new technical solutions for end-of=life processes, such as reuse/recycling, final treatment or disposal.

…

Within NanoSustain an assessment has been made of the PC properties, exposure and toxicity, energy and material inputs and outputs at relevant stages of a material or product’s life-cycle. This means: material production, processing, manufacturing, use, transportation, and end-of-life (recycling/disposal). At each stage potential risks to human health and the environment have also been assessed, through a number of experimental models and test systems using materials that would be expected to be released from products containing nanomaterials.

Four nanomaterials were investigated that either already feature in commercial products or are expected to be commercialized on a large scale: titanium dioxide (TiO2) in paint, zinc oxide (ZnO) as a coating for glass, multi-walled carbon nanotubes (MWCNT) in epoxy resins, and nanocellulose in paper.

Detailed information on the nanomaterials have been summarized in internal project material datasheets (MDS), and will be made available as part of peer-reviewed publications on release studies and toxicological investigations. [emphases mine]

Having looked at the four case studies, each of which is two pages, I would describe them as teasers. There’s not a lot of information in them as to the results of the testing which makes sense when you see that they will be publishing in various publications.

I find the inclusion of titanium dioxide, zinc oxide and carbon nanotubes for life-cycle assessments easily understandable as they  have been integrated into many consumer products. However, it’s my understanding that nanocellulose has not reached that level of product integration. Still, given the number of times I’ve been told this is a ‘safe’ product, it’s interesting to see what NanoSustain has to say about its toxicity (from the NanoSustain’s nanocellulose case study),

Work in NanoSustain has provided new data and information on the physicochemical properties, potential human and environmental hazard and risk associated with relevant stages of the life-cycle of nanocellulose based products as well as on the overall energy and material input/output that may happen during manufacturing, use and disposal. Initial results indicate that the nanocellulose degrades efficiently under standard composting conditions, but does not in aquatic environments. Furthermore nanocellulose does not demonstrate any ecotoxicity. Unfortunately nanocellulose forms a gel when suspended in media for inhalation studies, and so no toxicology experiments could be performed (as for the other engineered nanomaterials studied in NanoSustain). Final results will be made available once published in peer-reviewed journals.

I have written many times about nanocellulose, a topic featuring some interesting and confusing nomenclature and taking this opportunity to highlight a couple of responses from folks who took the time to clarify things for me (from my Aug. 2, 2012 posting),

KarenS says:

Hi Maryse!

From my understanding, nanocrystaline cellulose (NCC), cellulose nanocrystals (CNC), cellulose whiskers (CW) and cellulose nanowhiskers (CNW) are all the same stuff: cylindrical rods of crystalline cellulose (diameter: 5-10 nm; length: 20-1000 nm). Cellulose nanofibers or nanofibrils (CNF), on the contrary, are less crystalline and are in the form of long fibers (diameter: 20-50 nm; length: up to several micrometers).

There is still a lot of confusion on the nomenclature of cellulose nanoparticles, but nice explanations (and pictures!) are given here (and also in other papers from the same conference):

http://www.tappi.org/Downloads/Conference-Papers/2012/12NANO/12NANO49.aspx

and there’s this from my Sept. 26, 2012 posting,

Gary Chinga Carrasco says:

The definition of cellulose nanofibrils as “diameter: 20-50 nm; length: up to several micrometers)” is somewhat simplified. For terminology on MFC terms you may want to take a look at: http://www.nanoscalereslett.com/content/6/1/417

Bringing this piece back to where I started, I look forward to seeing the NanoSustain case studies published with more details in the future.

Note: Since the folks at NanoSustain are likely using their form to collect data, I’m not linking back to the factsheet or nanocellulose case study as I would usually. So, if you want to look at the material, you do need to register via the form.

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Disorder engineering turns ‘white’ nanoparticles to ‘black’ nanoparticles for clean energy

Wednesday, April 10th, 2013

Titanium dioxide crystals are white, except when they’re black. According to an Apr. 10, 2013 news item on Nanowerk, researchers at the Lawrence Berkeley National Laboratory (US) have found a way to change white titanium dioxide crystals to black thereby changing some of their properties,

A unique atomic-scale engineering technique for turning low-efficiency photocatalytic “white” nanoparticles of titanium dioxide into high-efficiency “black” nanoparticles could be the key to clean energy technologies based on hydrogen.

Samuel Mao, a scientist who holds joint appointments with Berkeley Lab’s Environmental Energy Technologies Division and the University of California at Berkeley, leads the development of a technique for engineering disorder into the nanocrystalline structure of the semiconductor titanium dioxide. This turns the naturally white crystals black in color, a sign that the crystals are now able to absorb infrared as well as visible and ultraviolet light. The expanded absorption spectrum substantially improves the efficiency with which black titanium dioxide can use sunlight to split water molecules for the production of hydrogen.

The Apr. 10, 2013 Berkeley Lab news release, which originated the news item, provides more detail about how this discovery might have an impact on clean energy efforts,

The promise of hydrogen in batteries or fuels is a clean and renewable source of energy that does not exacerbate global climate change. The challenge is cost-effectively mass-producing it. Despite being the most abundant element in the universe, pure hydrogen is scarce on Earth because hydrogen combines with just about any other type of atom. Using solar energy to split the water molecule into hydrogen and oxygen is the ideal way to produce pure hydrogen. This, however, requires an efficient photocatalyst that water won’t corrode. Titanium dioxide can stand up to water but until the work of Mao and his group was only able to absorb ultraviolet light, which accounts for barely ten percent of the energy in sunlight.In his ACS [American Chemical Society]  talk [at the 245th meeting, Apr. 7 - 11, 2013], titled “Disorder Engineering: Turning Titanium Dioxide Nanoparticles Black,” Mao described how he developed the concept of “disorder engineering,” and how the introduction of hydrogenated disorders creates mid-band gap energy states above the valence band maximum to enhance hydrogen mobility. His studies have not only yielded a promising new photocatalyst for generating hydrogen, but have also helped dispel some widely held scientific beliefs.

“Our tests have shown that a good semiconductor photocatalyst does not have to be a single crystal with minimal defects and energy levels just beneath the bottom of conduction band,” Mao said.

Characterization studies at Berkeley Lab’s Advanced Light Source also helped answer the question of how much of the hydrogen  detected in their experiments comes from the photocatalytic reaction, and how much comes from hydrogen absorbed in the titanium oxide during the hydrogenation synthesis process.

“Our measurements indicate that only a very small amount of hydrogen is absorbed in black titanium dioxide, about 0.05 milligrams, as compared to the 40 milligrams of hydrogen detected during a 100 hour solar-driven hydrogen production experiment,” Mao said.

I must say, this ‘disorder engineering’ sounds much more appealing than some of the other disorders one hears about (e.g. personality disorders).

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

Friday, February 8th, 2013

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

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

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

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

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

Then, she has some dodgier material,

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

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

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

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

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

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

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

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

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

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

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

Happy Weekend!

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Canada-US Regulatory Cooperation Council’s Nanotechnology Work Plan

Monday, December 3rd, 2012

Thanks for Lynn L. Bergeson for her Dec. 1, 2012 posting on the Nanotechnology Now website for the information about a Nov. 28, 2012 webinar that was held to discuss a Nanotechnology Work Plan developed by the joint Canada-US Regulatory Cooperation Council (or sometimes it’s called the US-Canada Regulatory Cooperation Council),

…

The RCC requested that industry provide more information on the commercial distribution of nanomaterials, as well as more transparency by claiming confidentiality of only that information absolutely critical to market advantage.

To compare risk assessment and risk management practices to highlight and identify best practices, data gaps, and differences between the two jurisdictions, the RCC sought nominations of a nanomaterial substance for a case study. Four nanomaterial substances were nominated: multiwall carbon nanotubes, nanocrystalline cellulose, nano silver, and titanium dioxide. The RCC has selected multiwall carbon nanotubes for the case study. The RCC intends to hold in March 2013 a workshop in Washington, D.C., to discuss information collected to date and approaches moving forward. In spring 2013, the RCC will hold one or two conference calls or webinars to discuss information gathered between countries and the path forward. Finally, in fall 2013, the RCC expects to hold a stakeholder consultation/workshop on results to date.

Here’s some background on the RCC. First announced in February 2011, the RCC had its first ‘stakeholder’ session (attended by approximately 240)  in January 2012 in Washington, DC. where a series of initiatives, including nanotechnology, were discussed (from the US International Trade Administration RCC Stakeholder Outreach webpage),

Agriculture and Food, Session A

  • Perimeter approach to plant protection

Agriculture and Food, Session B

  • Crop protection products

Agriculture and Food, Session C

  • Meat/poultry – equivalency
  • Meat/poultry – certification requirements
  • Meat cut nomenclature

Agriculture and Food, Session D

  • Veterinary drugs
  • Zoning for foreign animal disease

Agriculture and Food, Session E

  • Financial protection to produce sellers

Agriculture and Food, Session F

  • Food safety – common approach
  • Food safety – testing

Road Transport – Motor Vehicles

  • Existing motor vehicle safety standards
  • New motor vehicle safety standards

Air Transport

  • Unmanned aircraft

Transportation

  • Intelligent Transportation Systems

Transportation

  • Dangerous goods means of transportation

Marine Transport

  • Safety and security framework & arrangement for the St. Lawrence Seaway & Great Lakes System
  • Marine transportation security regulations
  • Recreational boat manufacturing standards
  • Standard for lifejackets

Rail Transport

  • Locomotive Emissions
  • Rail Safety Standards

Environment

  • Emission standards for light-duty vehicles

Personal Care Products & Pharmaceuticals

  • Electronic submission gateway
  • Over-the-counter products – common monographs
  • Good manufacturing practices

Occupational Safety Issues

  • Classification & labelling of workplace hazardous chemicals

Nanotechnology

  • Nanotechnology

Led jointly by senior officials from Canada and the United States, the purpose of the various technical review sessions was to seek expert advice and technical input from the approximately 240 stakeholders in attendance.

Since the Jan. 2012 meeting, a Nanotechnology Work Plan has been developed and that’s what was recently discussed at the Nov. 28, 2012 webinar. I did find more on a Canadian government website, Canada’s Economic Action Plan Nanotechnology Work Plan webpage,

Nanotechnology Work Plan

 Canada Leads: Karen Dodds, Assistant Deputy Minister, Science and Technology Branch, Environment Canada (EC)

Hilary Geller, Assistant Deputy Minister, Healthy Environments and Consumer Safety Branch, Health Canada (HC)

U.S. Lead: Margaret Malanoski, Office of Information and Regulatory Affairs, Office of Management and Budget

Deliverable Outcome: Share information and develop common approaches, to the extent possible, on foundational regulatory elements, including criteria for determining characteristics of concern/no concern, information gathering, approaches to risk assessment and management, etc. Develop joint initiatives to align regulatory approaches in specific areas such that consistency exists for consumers and industry in Canada and the US.

Principles: Identification of common principles for the regulation of nanomaterials to help ensure consistency for industry and consumers in both countries

3-6 months:

Canada provides initial feedback on US “Policy Principles for the US Decision-Making Concerning Regulation and Oversight of Applications of Nanotechnology and Nanomaterials”.

6-12 months:

Countries complete an initial draft of shared principles for the regulation of nanomaterials.

12-18 months:

Update of draft principles informed from on-going stakeholder and expert consultations.

18th month:

Stakeholder consultation / workshop on results to date and future ongoing engagement.

Beyond 18 months:

Countries complete final draft of shared principles for the regulation of nanomaterials.

Workplan for Industrial Nanomaterials

Priority-Setting: Identify common criteria for determining characteristics of industrial nanomaterials of concern/no-concern

1-3 months:

  1. Define and finalize workplan (1st month)
  2. Develop mechanisms for stakeholder outreach and engagement (1st month)
  3. Conference call with relevant stakeholders to share and discuss workplan and call for Industry to volunteer nanomaterials for joint CAN/US review

3-6 months:

Share available scientific evidence regarding characteristics of industrial nanomaterials including that obtained from existing international fora (e.g. OECD Working Party on Manufactured Nanomaterials [Canada is a lead in the OECD Working Party on Manufactured Nanomaterials]).

8th month:

Stakeholder workshop to discuss information collected to date and approaches moving forward.

6-12 months:

Initiate an analysis of characteristics of select nanomaterials: similarities, differences, reasons for them.

Initiate discussions on approaches to consider for common definitions and terminology.

12th month:

Second conference call with relevant stakeholders to discuss non-CBI information gathered between the Countries and to discuss path forward in terms of development of reports and analyses.

12-18 months:

Develop draft criteria for determining characteristics of industrial nanomaterials of concern/no-concern.

15th month:

Third conference call with relevant stakeholders to discuss progress and to prepare for the upcoming stakeholder consultation/workshop.

…

Here’s information for the leads should you feel compelled to make contact,

Canada

(Lead) Karen Dodds, Assistant Deputy Minister, Science and Technology, Environment Canada (karen.dodds@ec.gc.ca; ph. 613- 819-934-6851)

Hilary Geller, Assistant Deputy Minister, Healthy Environments and Consumer Safety Branch (hilary.geller@hc-sc.gc.ca; ph. 613-946-6701)

United States

(Lead) Margaret Malanoski, Office of Management and Budget (Margaret_A._Malanoski@omb.eop.gov)

I gather that the ‘stakeholders’ are business people, researchers, and policy analysts/makers as there doesn’t seem to be any mechanism for public consultation or education, for that matter.

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Change your gloves frequently if you’re handling nanoparticles

Thursday, June 14th, 2012

Québec’s IRSST (Institut de recherche Robert-Sauvé en santé et en sécurité du travail) has issued a May 16, 2012 news release about the results of a study on gloves and nanoparticles,

After developing a sampling protocol and selecting the best analysis and measurement techniques, the research team carried out preliminary tests using four models of nitrile, latex, neoprene and butyl rubber protective gloves and commercial titanium dioxide (TiO2) nanoparticles in powder and colloidal solution form. “The results appear to indicate that powder nanoparticles penetrated the disposable nitrile gloves after seven hours of repeated deformation, while the butyl gloves appeared to be impermeable,” explained investigator Patricia Dolez, the main author of the report. “As for nanoparticles in colloidal solutions, we measured a possibility of penetration through the gloves, in particular when the gloves were subjected to repeated deformation. These preliminary data, which need to be validated by additional studies, show that it is important to continue work in this field.”

…

Based on the results, the research team recommends that care be taken when choosing and using this type of personal protective equipment. “We recommend replacing, at regular intervals, protective gloves that are worn, especially thinner gloves, and gloves that have been exposed to nanoparticles in colloidal solutions,” Dr. Dolez concluded.

H/T to the June 14, 2012 news item on Nanowerk for alerting me to this work.

You can get a copy of the study, Développement d’une méthode de mesure de la pénétration des nanoparticules à travers les matériaux de gants de protection dans des conditions simulant l’utilisation en milieu de travail , but it is in French only, as of today June 14, 2012. The abstract has been translated into English. I last mentioned one of the investigators, Patricia Dolez, in passing in my Oct. 14, 2009 posting.

ETA June 14, 2012: I should also have mentioned that this was joint project with researchers from the École de technologie supérieure, École Polytechnique, and Université de Montréal were working on this project with the team from IRSST.

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Sri Lanka’s nano

Monday, June 4th, 2012

Carol Aloysius’ May 27, 2012 article for Sri Lanka’s The Nation newspaper highlights both the country’s nanotechnology’s efforts and one of its leading nanoscientists, Prof Veranja Karunaratne,

Five years ago, a unique initiative was launched through the Sri Lanka Institute of Nanotechnology (SLINTEC). The Nanotechnology Initiative (NNI) which is a public-private partnership aimed at providing platform research solutions based on nanotechnology to the Sri Lankan industries has not only attracted global recognition, it has earned the man responsible for driving it to its current global status a coveted award from the French government.

“The vision of NNI is to facilitate development and make Sri Lanka an industrial power in order to enable the country to emerge from poverty by infusing nanotechnology based innovations through research and development utilizing local raw materials, resources and talent. In order to fast-tract the NNI, the Government proposed the setting up of SLINTEC, the first ever Government funded start-up research company,” says Prof Veranja Karunaratne.

A fortnight ago, on May 11, Prof Karunaratne who is a Senior Professor in the Department of Chemistry, University of Peradeniya, and for the last few years, Science Team Leader, Sri Lanka Institute of Nanotechnology (SLINTEC), was conferred the distinction of Chevalier dans l’ordre des Palmes Académiques, in recognition of his personal involvement in the promotion of French language and culture in Sri Lanka.

Aloysius’ article goes on to discuss some of Sri Lanka’s NNI initiatives and Karunaratne’s hopes for the country’s future,

SLINTEC which started research in August 2009, thus far, has applied for five patents at the United States Patent Office to cover the innovations for its joint venture partners, he notes. “Two of the patents pertained to the slow release nanofertilizer formulations which release nitrogen to the soil in slow, sustained manner. These two patents attracted the attention of Nagarjuna Fertilizer and Chemicals Limited (NFCL) a global leader in the manufacture of fertilizer, and in a landmark scientific development, SLINTEC entered into a strategic collaboration with NFCL of Hyderabad, India, to develop the next generation of nanotechnology based plant fertilizer solutions.

…

In the area of value addition to Sri Lankan natural resources, SLINTEC entered into an agreement with Laughs Gas (Pvt) Ltd. to build a pilot plant to convert Ilmenite to Titanium Dioxide and nano-Titanium Dioxide. This agreement paves the way to the commercial production of Titanium Dioxide from the high purity Ilmentite ore whose value addition had remained elusive during the past decades while Sri Lanka exported sand to foreign countries.

The whole rationale behind this concept, is for SLINTEC to take the nation from, being   commodity sellers to a Smart Nation – a nation that generates and sells technology, he explains. [emphasis mine] He is convinced that this will happen in the near future, where Sri Lanka will be on par with other developed nations.

I think more than one Canadian can empathize with the desire to move your nation awary from being a commodity seller.

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New research on nanoscale titanium dioxide shows toxic effects on marine life

Thursday, January 26th, 2012

Up till now, nanoscale titanium dioxide in water has not been viewed as toxic to marine life. A newly released study by researchers from  the University of California (UC) Center for Environmental Implications of Nanotechnology (UC CEIN) in the Jan. 20 in the journal PLoS ONE suggests otherwise. From the Jan. 24, 2012 news release on EurekAlert,

“Previous experiments have suggested that TiO2 does not affect aquatic organisms, but these experiments used artificial lighting that generated much lower levels of UVR than sunlight,” Miller [lead author and assistant research biologist Robert Miller] explains. “In these new experiments, we used lights simulating natural sunlight.”

But now, the authors say, “We show that relatively low levels of ultraviolet light, consistent with those found in nature, can induce toxicity of TiO2 nanoparticles to marine phytoplankton, the most important primary producers on Earth.

So, the relatively low levels of ultraviolet light in natural sunlight can induce toxicity in titanium dioxide nanoparticles. Here’s the reason for the concern,

“Application of nanomaterials in consumer products and manufacturing is quickly increasing, but there is concern that these materials, including nanoparticles, may harm the environment,” says Miller. “The oceans could be most at risk, since wastewater and factory discharges ultimately end up there.”

In all of the kerfuffle that the Friends of the Earth (FoE) and The ETC Group (and I assume others as well) have made over nanoscale ingredients in sunscreens they seem to have ignored the impact that these ingredients, when washed off our skin and into our water supply, may have on aquatic life.  I wonder if that will matter in the end. I mean if it turns out that nanoscale titanium dioxide is going to kill/damage “… the most important primary producers on Earth”, does it matter if FoE and the others succeed in mobilizing opposition to its use for what most experts might consider the wrong reasons.

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Misunderstanding the data or a failure to research? Georgia Straight article about nanoparticles

Tuesday, July 26th, 2011

It’s good to see articles about nanotechnology. The recent, Tiny nanoparticles could be a big problem, article written by Alex Roslin for the Georgia Straight (July 21, 2011 online or July 21-28, 2011 paper edition) is the first I’ve seen on that topic in that particular newspaper. Unfortunately, there are  some curious bits of information included in the article, which render it, in my opinion, difficult to trust.

I do agree with Roslin that nanoparticles/nanomaterials could constitute a danger and there are a number of studies which indicate that, at the least, extreme caution in a number of cases should be taken if we choose to proceed with developing nanotechnology-enabled products.

One of my difficulties with the article is the information that has been left out. (Perhaps Roslin didn’t have time to properly research?) At the time (2009) I did read with much concern the reports Roslin mentions about the Chinese workers who were injured and/or died after working with nanomaterials. As Roslin points out,

Nanotech already appears to be affecting people’s health. In 2009, two Chinese factory workers died and another five were seriously injured in a plant that made paint containing nanoparticles.

The seven young female workers developed lung disease and rashes on their face and arms. Nanoparticles were found deep in the workers’ lungs.

“These cases arouse concern that long-term exposure to some nanoparticles without protective measures may be related to serious damage to human lungs,” wrote Chinese medical researchers in a 2009 study on the incident in the European Respiratory Journal.

Left undescribed by Roslin are the working conditions; the affected people were working in an unventilated room. From the European Respiratory Journal article (ERJ September 1, 2009 vol. 34 no. 3 559-567, free access), Exposure to nanoparticles is related to pleural effusion, pulmonary fibrosis and granuloma,

A survey of the patients’ workplace was conducted. It measures ∼70 m2, has one door, no windows and one machine which is used to air spray materials, heat and dry boards. This machine has three atomising spray nozzles and one gas exhauster (a ventilation unit), which broke 5 months before the occurrence of the disease. The paste material used is an ivory white soft coating mixture of polyacrylic ester.

Eight workers (seven female and one male) were divided into two equal groups each working 8–12 h shifts. Using a spoon, the workers took the above coating material (room temperature) to the open-bottom pan of the machine, which automatically air-sprayed the coating material at the pressure of 100–120 Kpa onto polystyrene (PS) boards (organic glass), which can then be used in the printing and decorating industry. The PS board was heated and dried at 75–100°C, and the smoke produced in the process was cleared by the gas exhauster. In total, 6 kg of coating material was typically used each day. The PS board sizes varied from 0.5–1 m2 and ∼5,000 m2 were handled each workday. The workers had several tasks in the process including loading the soft coating material in the machine, as well as clipping, heating and handling the PS board. Each worker participated in all parts of this process.

Accumulated dust particles were found at the intake of the gas exhauster. During the 5 months preceding illness the door of the workspace was kept closed due to cold outdoor temperatures. The workers were all peasants near the factory, and had no knowledge of industrial hygiene and possible toxicity from the materials they worked with. The only personal protective equipment used on an occasional basis was cotton gauze masks. According to the patients, there were often some flocculi produced during air spraying, which caused itching on their faces and arms. It is estimated that the airflow or turnover rates of indoor air would be very slow, or quiescent due to the lack of windows and the closed door. [emphases mine]

Here’s the full text from the researchers’ conclusion,

In conclusion, these cases arouse concern that long-term exposure to some nanoparticles without protective measures may be related to serious damage to human lungs. It is impossible to remove nanoparticles that have penetrated the cell and lodged in the cytoplasm and caryoplasm of pulmonary epithelial cells, or that have aggregated around the red blood cell membrane. Effective protective methods appear to be extremely important in terms of protecting exposed workers from illness caused by nanoparticles.

There is no question that serious issues about occupational health and safety with regards to nanomaterials were raised. But, we work with dangerous and hazardous materials all the time; precautions are necessary whether you’re working with hydrochloric acid or engineered nanoparticles. (There are naturally occurring nanoparticles too.)

Dr. Andrew Maynard (at the time he was the Chief Science Advisor for the Project on Emerging Nanotechnologies, today he is the Director of the University of Michigan’s Risk Science Center) on his 2020 Science blog wrote a number of posts dated Aug. 18, 2009 about this tragic industrial incident, including this one where he culled comments from six other researchers noting some of the difficulties the Chinese researchers experienced running a clinical study after the fact.

The material on silver nanoparticles and concerns about their use in consumer products and possible toxic consequences with their eventual appearance in the water supply seem unexceptionable to me. (Note:  I haven’t drilled down into the material and the writer cites studies unknown to me but they parallel information I’ve seen elsewhere).

The material on titanium dioxide as being asbestos-like was new to me, the only nanomaterial I’d previously heard described as being similar to asbestos is the long carbon nanotube. I am surprised Roslin didn’t mention that occupational health and safety research which is also quite disturbing, it’s especially surprising since Roslin does mention carbon nanotubes later in the article.

There is a Canadian expert, Dr. Claude Ostiguy, who consults internationally on the topic of nanotechnology and occupational health and safety. I wonder why he wasn’t consulted. (Note: He testified before Canada’s House of Commons Standing Committee on Health meeting in June 2010 on this topic. You can find more about this in my June 23, 2011 posting, Nanomaterials, toxicity, and Canada’s House of Commons Standing Committee on Health.)

Quoted quite liberally throughout the article is researcher, Dr.Robert Schiestl (professor of pathology and radiation oncology at the University of California at Los Angeles [UCLA]). This particular passage referencing Schiestl is a little disconcerting,

Schiestl said nanoparticles could also be helping to fuel a rise in the rates of some cancers. He wouldn’t make a link with any specific kind of cancer, but data from the U.S. National Cancer Institute show that kidney and renal-pelvis cancer rates rose 24 percent between 2000 and 2007 in the U.S., while the rates for melanoma of the skin went up 29 percent and thyroid cancer rose 54 percent.

Since Schiestl isn’t linking the nanoparticles to any specific cancers, why mention those statistics? Using that kind of logic I could theorize that the increase in the number and use of cell phones (mobiles) may have something to do with these cancers. Perhaps organic food has caused this increase? You see the problem?

As for the number of nanotechnology-enabled products in use, I’m not sure why Roslin chose to cite the Project on Emerging Nanotechnologies’ inventory which is not scrutinized, i. e., anyone can register any product as nanotechnology-enabled. The writer also mentioned a Canadian inventory listing over 1600 products  cited in an ETC Group report, The Big Downturn? Nanogeopolitics,

Has anyone ever seen this inventory? I’ve been chasing it for years and the only time the Canadian government reports on this inventory is in the Organization for Economic Cooperation and Development (OECD) report (cited by the ETC Group [no. 79 in their list of references] and noted in both my Feb. 1, 2011 posting and my April 12, 2010 posting). Here’s the OECD report, if you’d like to see it for yourself. The top three questions I keep asking myself is where is the report/inventory, how did they determine their terms of reference, and why don’t Canadian taxpayers have easy access to it? I’d best return to my main topic.

As for the material Roslin offers about nanosunscreens I was surprised given the tenor of the article to see that the Environmental Working Group (EWG) was listed as an information source since they recommend mineral sunscreens containing nanoscale ingredients such as titanium dioxide and/or zinc oxide as preferable to sunscreens containing hormone disruptors.  From the EWG page on sunscreens and nanomaterials,

Sunscreen makers offer mineral and non-mineral formulations, as well as products that combine both mineral and non-mineral active ingredients. Mineral formulations incorporate zinc oxide or titanium dioxide in nano- and micro-sized particles that can be toxic if they penetrate the skin. Most studies show that these ingredients do not penetrate through skin to the bloodstream, but research continues. These constitute one in five sunscreens on the market in 2010 and offer strong UVA protection that is rare in non-mineral sunscreens.

The most common ingredients in non-mineral sunscreens are oxybenzone, octisalate, octinoxate, and avobenzone found in 65, 58, 57, and 56 percent of all non-mineral sunscreens on the market, respectively. The most common, oxybenzone, can trigger allergic reactions, is a potential hormone disruptor and penetrates the skin in relatively large amounts. Some experts caution that it should not be used on children. Three of every five sunscreens rated by EWG are non-mineral, and one in five sunscreens combines both mineral and non-mineral active ingredients.

EWG reviewed the scientific literature on hazards and efficacy (UVB and UVA protection) for all active ingredients approved in the U.S. Though no ingredient is without hazard or perfectly effective, on balance our ratings tend to favor mineral sunscreens because of their low capacity to penetrate the skin and the superior UVA protection they offer. [emphasis mine]

(I did find some information (very little) about Health Canada and sunscreens which I discuss in June 3, 2011 posting [if you're impatient, scroll down about 1/2 way].)

There was some mention of Health Canada in Roslin’s article but no mention of last year’s public consultation, although to be fair, it seemed a clandestine operation. (My latest update on the Health Canada public consultation about a definition for nanomaterials is May 27, 2011.)

I find some aspects of the article puzzling as Roslin is an award-winning investigative reporter. From the kitco bio page,

Alex Roslin is a leading Canadian investigative journalist and active trader based in Montreal. He has won a Canadian Association of Journalists award for investigative reporting and is a five-time nominee for investigative and writing prizes from the CAJ and the National Magazine Awards. He has worked on major investigations for Canada’s premier investigative television program, the fifth estate, and the CBC’s Disclosure program. His writing has appeared in Technical Analysis of Stocks & Commodities, The Financial Post, Toronto Star and Montreal Gazette. He regularly writes about investing for The Montreal Gazette.

I notice there’s no mention of writing in either science or health matters so I imagine this is an early stage piece in this aspect of Roslin’s career, which may explain some of the leaps in logic and misleading information. Happily, I did learn a few things from reading the article and while I don’t trust much of the information in it, I will investigate further as time permits.

In general, I found the tenor of the article more alarmist than informational and I’m sorry about that as I would like to see more information being shared and, ultimately, public discussion in Canada about nanotechnology and other emerging technologies.

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Nanotechnology-enabled Catalytic Clothes look good and clean the air

Friday, July 8th, 2011

There’s a great video on the RIA Novosti website featuring interviews about an art/science collaboration between Professor Helen Storey at the London College of Fashion and Professor Tony Ryan, a scientist at the University of Sheffield. The two have created clothing that cleans the air of pollution. From the University of Sheffield June 15, 2011 news release,

Catalytic Clothing is a radical partnership between the University of Sheffield and London College of Fashion University of the Arts London that brings together the worlds of fashion and chemistry with the potential to clean the air we breathe. Employing existing technology in a new way, it seeks to explore how clothing and textiles can be used as a catalytic surface to purify air. It is the brainchild of artist/designer Professor Helen Storey MBE and chemist Professor Tony Ryan OBE – people from two very differing worlds who are using their diametric approaches to achieve great things. Previous projects include the groundbreaking Wonderland project which has now been seen by over 11 million people worldwide.

…
An exclusive film starring Erin O’Connor with soundtrack by Radiohead is already going viral with millions of views.

Here’s a brief preview of the film,

Here’s a link to the Catalytic Clothing website where you can see the entire film.

For those interested in the science part of the Catalytic Clothing story (from the Catalytic Clothing website, Scientific Background/FAQS page),

What is the science behind Catalytic Clothing?

Catalytic Clothing harnesses the power of a photocatalyst to break down air borne pollutants. A catalyst is a term used to describe something that makes a reaction proceed at a greater rate but isn’t actually consumed during that reaction. A photocatalyst gains the energy it needs to be active from light.

Where do the pollutants come from?

The two biggest sources of air borne pollutants are industry and motor vehicles. Although the majority of the pollutants are prevented from reaching the air, using technology such as catalytic converters, some do escape. It is these pollutants that Catalytic Clothing will break down.

How are the pollutants broken down?

When the light shines on the photocatalyst, the electrons in the material are rearranged and they become more reactive. These electrons are then able to react with the water in the air and break it apart into 2 radicals. A radical is an extremely reactive molecule. These radicals then react with the pollutants and cause them to break down into non-harmful chemicals.

What happens to the pollutants after they’ve been broken down?

The Catalytic Clothing technology is designed to breakdown the pollutants straight away. However, some pollutants may become attached without being broken down. In this case, the pollutants will be washed off during subsequent laundering. This actually already happens with normal clothing.

Is this technology used in any other products?

Photocatalysts have been incorporated into several commercially available products that possess de-polluting properties. These products include paints, cements and paving stones. [Note 1: In the RIA Novosti video, Ryan mentions titanium dioxide specifically. Note 2: Coatings for pavements in Germany are mentioned in my August 2, 2010 posting; scroll down 1/2 way.]

How is the technology delivered to the surface of the clothing?

The photocatalyst is delivered to the surface of the clothing during the traditional laundry procedure as an additive within a standard product such as a fabric conditioner. The active agent is packaged within a shell that is attracted towards, and subsequently binds to, the surface of the clothing during the washing cycle.

Why do we need mass participation to produce a noticeable reduction in the level of pollution?

Although any garment that is treated with the product becomes active, a single garment is only able to remove a small proportion of the air borne pollutants. Therefore, a large number of individuals, all acting together, is required to produce a noticeable reduction in the level of pollution.

How many people would need to participate to produce a noticeable reduction in the level of pollution?

An estimate of the required level of uptake for the Catalytic Clothing indicates that a significant reduction in the level of air borne pollutants in a large city such as London could be achieved if, for every metre of pavement width, 30 people wearing Catalytic Clothes walked past each minute.

Would someone wearing Catalytic Clothing be at a greater risk of exposure to pollutants?

No. The Catalytic Clothing technology won’t actively attract any pollutants. Instead, it will break down anything that comes within very close proximity of the photocatalyst’s surface.

How would society benefit if Catalytic Clothing was widely introduced?

Exposure to air borne pollutants presents a risk to human health and also has a detrimental effect on ecosystems and vegetation. Air pollution is currently estimated to reduce the life expectancy of every person in the UK by an average of 7-8 months. The widespread introduction of Catalytic Clothing would dramatically reduce the level of air borne pollutants, thereby improving the quality of life for all members of society.

The main sponsor for the project is Ecover (from the news release),

Ecover, who are the main sponsors of the Catalytic Clothing cultural campaign, are one of the world´s leading suppliers of green and sustainable cleaning products. All of their products are made with fully renewable plant-based ingredients and produced using a totally biochemical process. Ecover has been recognised by the United Nations Environment programme (UNEP) for their outstanding practical achievements for the protection and improvement of our environment.

Here’s the Ecover website.

This really is the last posting for today. Happy Weekend!

ETA July 11, 2011: Here’s a posting by Jasmin Malik Chua about the project at the Ecouterre website.

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