Tag Archives: Kevin Wilkinson

Gloves, Québec’s (Canada) Institut de recherche Robert-Sauvé en santé et en sécurité du travail, and a workplace nanotoxicity methodology report

A new report on a workplace health and safety issue in regard to nanoparticles (Development of a Method of Measuring Nanoparticle Penetration through Protective Glove Materials under Conditions Simulating Workplace Use)  was released in June 2013 by Québec’s Institut de recherche Robert-Sauvé en santé et en sécurité du travail (IRSST). Little research has been done on exposure through skin (cutaneous exposure), most research has focused on exposure by inhalation according to the report (en français version here),

In the workplace, the main pathway to NP exposure is inhalation (Ostiguy et al., 2008a). Exposure by the cutaneous route has not been studied much, partly because of the widely held belief that skin offers an impermeable barrier to NPs (Truchon et al., 2008). Yet a growing number of studies have pointed to the possible percutaneous absorption of NPs, such as in the case of skin damaged by abrasion (Zhang et al., 2008), repeated flexion (Rouse et al., 2007) or even through intact skin (Ryman-Rasmussen et al., 2006). Pores, hair follicles and sweat glands may also play a role in facilitating absorption of NPs through the skin (Hervé-Bazin, 2007). The nanoparticles are then carried throughout the body by the lymphatic circulatory system (Papp et al., 2008). Induced direct toxic effects have also been reported for epidermal keratinocyte cells exposed to carbon nanotubes and other types of NPs (Shvedova, 2003). [p. 17 PDF version; p. 1 print version; Note: See report bibliography for citations]

The researchers examined gloves made of four different types of material: nitrile, latex, neoprene, and butyl rubber under a number of different conditions. One type of nanoparticle was used for the study, titanium dioxide in powder and liquid forms. The report summary provides a bit more detail about the decision to develop a methodology and the testing methods,

With the exponential growth in industrial applications of nanotechnologies and the increased risk of occupational exposure to nanomaterials, the precautionary principle has been recommended. To apply this principle, and even though personal protective equipment against nanoparticles must be considered only as a last resort in the risk control strategy, this equipment must be available. To respond to the current lack of tools and knowledge in this area, a method was developed for measuring the penetration of nanoparticles through protective glove materials under conditions simulating workplace use.

This method consists of an experimental device for exposing glove samples to nanoparticles in powder form or in colloidal solution, while at the same time subjecting them to static or dynamic mechanical stresses and conditions simulating the microclimate in the gloves. This device is connected to a data control and acquisition system. To complete the method, a sampling protocol was developed and a series of nanoparticle detection techniques was selected.

Preliminary tests were performed using this method to measure the resistance of four models of protective gloves of different thicknesses made of nitrile, latex, neoprene and butyl to the passage of commercial TiO2 nanoparticles in powder form or colloidal solution. The results seem to indicate possible penetration of the nanoparticles in some types of gloves, particularly when subjected to repeated mechanical deformation and when the nanoparticles are in the form of colloidal solutions. Additional work is necessary to confirm these results, and consideration should be given to the selection of the configurations and values of the parameters that best simulate the different possible workplace situations. Nevertheless, a recommendation can already be issued regarding the need for regular replacement of gloves that have been worn, particularly with the thinnest gloves and when there has been exposure to nanoparticles in colloidal solution.

For interested parties, here’s a citation for and a link to the report (PDF),

Development of a Method of Measuring Nanoparticle Penetration through Protective Glove Materials under Conditions Simulating Workplace Use by Dolez, Patricia; Vinches, Ludwig; Perron, Gérald; Vu-Khanh, Toan; Plamondon, Philippe; L’Espérance, Gilles; Wilkinson, Kevin; Cloutier, Yves; Dion, Chantal; Truchon, Ginette
Studies and Research Projects / Report  R-785, Montréal, IRSST, 2013, 124 pages.

I last wrote about gloves and toxicity in a June 11, 2013 posting about gloves with sensors (they turned blue when exposed to toxic levels of chemicals). It would be interesting if they could find a way to create gloves with sensors that warn you when you are reaching dangerous levels of exposure through your gloves. Of course, first they’d have to determine what constitute a dangerous level of exposure. The US National Institute of Occupational Health and Safety (NIOSH) recently released its recommendations for exposure to carbon nanofibers and carbon nanotubes (my April 26, 2013 posting). In layperson’s terms, the recommended exposure is close to zero exposure. Presumably, the decision was based on the principle of being ‘safe rather than sorry’.

One final comment about exposure to engineered nanoparticles through skin, to date there has been no proof that there has been any significant exposure via skin. In fact, the first significant breach of the skin barrier was achieved for medical research, Chad Mirkin and his team at Northwestern University trumpeted their research breakthrough (pun intended) last year, from my July 4, 2012 posting,

Researchers at Northwestern University (Illinois, US) have found a way to deliver gene regulation technology using skin moisturizers. From the July 3, 2012 news item on Science Blog,

A team led by a physician-scientist and a chemist — from the fields of dermatology and nanotechnology — is the first to demonstrate the use of commercial moisturizers to deliver gene regulation technology that has great potential for life-saving therapies for skin cancers.

The topical delivery of gene regulation technology to cells deep in the skin is extremely difficult because of the formidable defenses skin provides for the body. The Northwestern approach takes advantage of drugs consisting of novel spherical arrangements of nucleic acids. These structures, each about 1,000 times smaller than the diameter of a human hair, have the unique ability to recruit and bind to natural proteins that allow them to traverse the skin and enter cells.

This goes a long way to explaining why primary occupational health and safety research has focused on exposure via inhalation rather than skin.  That said, I think ensuring safety means minimizing exposure by all routes until more is known about the hazards.

ÉquiNanos, Québec’s innovative nanoparticle risk management team

ÉquiNanos as described in the January 2013 issue of Nanomedicine: Nanotechnology, Biology, Medicine is both the name for an interdisciplinary nanoparticle risk management team and a model for managing that risk.

Before going further, here’s a citation and a link (if you want to see the article for yourself it is behind a paywall but everyone can get access to the abstract),

EquiNanos: innovative team for nanoparticle risk management by Sylvie Nadeau, Michèle Bouchard, Maximilien Debia, MSc, Nathalie DeMarcellis-Warin, Stéphane Hallé, Victor Songmene, Eng, Marie-Christine Therrien, Kevin Wilkinson, Barthélémy Ateme-Nguema, Geneviève Dufour, André Dufresne, Julien Fatisson, Sami Haddad, Madjid Hadioui, Jules Kouam, François Morency, Robert Tardif, Martin Viens, Scott Weichenthal, Claude Viau, Michel Camus. Nanomedicine. 2013 Jan;9(1):22-4. doi: 10.1016/j.nano.2012.08.003. Epub 2012 Sep 6.

Here’s how the Québec-based and funded authors define the issues, excerpted  from the ÉquiNanos article (Note: Footnotes have been removed),

… Lack of proper evaluation of real risks might threaten to undermine the competitiveness of nanotechnologies. In spite of multiple efforts for more general regulations, and there is currently no specific regulation governing particle size-distribution, and no consensus on the benefits of protection or on the level of safety afforded by proposed protective measures. The different perspectives of the various actors (scientists, industrials, workers, the Occupational Safety and Health Commission (CSST-Quebec), legislators, independent technologies promoters, media, public) regarding risk management reveal the need for an inter-sector approach that allows all groups to achieve their goals. …

Business organizations must manage risks associated with NP in a climate of scientific uncertainty, in the absence of a regulatory framework specifically adapted to NP and without a proven effective and efficient approach to risk management.

This is their proposed model,

ÉquiNanos consists of eight platforms (…): Adaptive decision-aid tool, public and legal governance, communication of risks, monitoring nano-aerosols at the source, evaluation and control of exposure, biological and kinetic monitoring, manufacturing,and preventative actions. Their coordination is based on a functionalistic research-action model allowing the ÉquiNanos team to get involved directly in order to transform business reality and to produce knowledge related to these transformations through communication with all stakeholders and agents of governance. The melting of disciplines and knowledge is the foundation of our inter-sector model.

The authors have provided a diagram of their proposed model,

Figure 1. Functionalistic research-action model – ÉquiNanos (OHS: Occupational Health and Safety). [downloaded from http://www.sciencedirect.com.proxy.lib.sfu.ca/science/article/pii/S1549963412005175]

Figure 1. Functionalistic research-action model – ÉquiNanos (OHS: Occupational Health and Safety). [downloaded from http://www.sciencedirect.com.proxy.lib.sfu.ca/science/article/pii/S1549963412005175]

Not surprisingly Dr. Claude Ostiguy and Dr. Andrew Maynard are both cited in the reference. Both are well known for their work in the field of risk management of nanoparticles and nanomaterials and were mentioned in my July 26, 2011 posting about a, then recent, sensationalist and somewhat inaccurate  nano risk article published in the Georgia Straight.

Équinanos looks like a reasonable model although implementation issues abound. Are businesses going to voluntarily participate? What percentage of businesses will volunteer? What about nanotechnology-enabled products that are manufactured elsewhere? What mechanism is there for transmitting and sharing information? No doubt these questions and more are being considered. It will be interesting to see if or how they manage to address these issues.