NIOSH questions causal role of nanoparticles in Chinese worker deaths

The National Institute for Occupational Safety and Health today posted a response to the ERJ paper that was heavily blogged about last week. There has been a lot of emphasis in the blogosphere on the limitations of the study, which could frustrate those who find the study compelling and feel its important lessons are getting lost amidst all the academic nit-picking.

But papers that omit critical details such as the type of nanoparticle and how it was created frustrate the ever-more-sophisticated nano-EHS crowd who are getting the message that these details matter for risk assessment. And it's pretty hard to impugn the credibility of NIOSH or to imply that it has anything other than workers' best interests in mind.

After reciting the essential facts surrounding the case, the NIOSH blog post poses many of the same questions others have raised with respect to the role of the nanoparticles in causing the illness and deaths:

"What was the concentration of nanoparticles in the paste/dust? What was the chemical composition of the nanoparticles found? Were the particles found in the paste/dust identical to the particles found in lung tissue and fluid? Since the exposure was to a complex chemical mixture, could other exposures in the workplace have caused the heart and lung disease?"

They go on to assert that:

"Despite the certainty inherent in their use of the term "nano material-related disease," the study authors have not provided us with scientific evidence nanoparticles were or were not the cause of the tragic medical consequences in these seven workers."

And, NIOSH being NIOSH, they conclude with a recommendation to adopt "a proactive, prudent approach to working with nanomaterials" and direct readers to their comprehensive nanotechnology topic page where one can find the latest version of Approaches to Safe Nanotechnology among many other useful resources. Check it out.

You like me, you really LIKE me

Much to my surprise, this humble blog showed up on a list of blog.com's 10 popular nanotechnology blogs. Since I'm expecting a veritable tsunami of new NanoRisk readers, I figured I had better say something clever today.

(KK: "something clever today.")

Seriously, I have no idea how this happened but if there was a vote, I'd like to thank each and every one of my 15 occasional readers for stuffing the ballot box. There are lots of great nano blogs out there that are sure to have 1.5-1.6 times my readership or more. A partial listing of the ones I read can be found in the links menu on the right. A more extensive list can be found in the blog I maintain more regularly.

I really should feed this beast more but will take heart that, even before today, this blog had been updated more recently than 95% of the blogs out there which haven't been updated in the past 120 days. On the other hand, if my gentle readers give me a sign, any sign, that I should spend more time posting random thoughts and non-ICON-related observations of the world of NanoRisk, I shall endeavor to respond.

It's OK, I don't expect you to leave a comment.

Estimating nano-titania production

It may be that WolframAlpha isn't sure what to do with my input but new research published this week could help. I asked WA a simple question, "What is the worldwide production of nanomaterials." Of course, I knew there was no good answer to the question but wanted to see if WA was accessing private sources of data or would attempt an answer based on unverified estimates that get bandied about periodically. WA demurred.

Quantifying production of nanoparticles is a tricky business, due in part to definitional issues and closely held industrial data. But understanding production volumes is a critical element in quantifying potential exposures to people or the environment. While nanoparticle hazard studies now abound, exposure studies lag far behind. Since risk must take into account both hazard and exposure, the lack of good exposure data hinders efforts to develop robust risk assessment protocols.

A new study from Duke University's Center for the Environmental Implications of NanoTechnology (CEINT, pronounced "saint") approaches the problem of quantifying the production of nano-titania using a combination of science and engineering knowledge and economic modeling. Starting with the worldwide production of non-nanoscale titania, which is more easily quantified, graduate student Christine Robichaud, professor and CEINT director Mark Wiesner and colleagues applied a "rate of innovation" from the biotechnology industry to estimate how much of the 2.5 million metric tons of titania produced in the US is and will be at the nanoscale.

Here's an estimated maximum nano-titania production as a fraction of total US titania production by year under the "most aggressive" scenario:


As is standard operating procedure for modeling papers that rely upon estimates and assumptions, caveats and qualifiers are sprinkled throughout the publication and I encourage you to read it for yourself. The paper's abstract can be accessed here. The journal lists the paper as "Sponsored Access" which I'm hoping means you do not have to pay to read it.

P.S. What's with these religious nano-acronyms, anyway? First ICON, now CEINT.

WolframAlpha isn't sure what to do with your input

My colleague Dr. Andrew Maynard gave up precious Saturday morning leisure time over the weekend to put WolframAlpha's new computational knowledge engine through its paces. Dr. Maynard, who goes by the handle @2020science on Twitter, solicited his followers for questions and then recorded the results. Curious about how WolframAlpha generates and validates the data it presents so beautifully, I submitted the question:

What is the worldwide production of nanoparticles?

The result was predictable:

WolframAlpha isn't sure what to do with your input.

Frankly, I'm more relieved than disappointed that this amazing new tool does not reach beyond its grasp and try to answer questions to which no authoritative source has the answer (another one being "what is love?" at which it completely FAILed). It will take more than a cool new tool to tackle such complex questions. On the other hand, WolframAlpha really shines when it comes to unit conversions. Now I have new analogies to use when speaking with grade-schoolers about the size of a nanometer.

I tweet at http://www.twitter.com/Kulinowski

International Standards for Risk Management of Nanotechnology

The current issue of Nature Nanotechnology contains an interesting exchange of letters between Peter Hatto, UK industrialist and chair of ISO/TC 229 Nanotechnologies and two NIOSH scientists, Vladimir Murashov and John Howard. (Howard is former NIOSH director.) Murashov and Howard published a commentary in the journal in 2008, in which they urged US government officials to become more heavily involved in setting international standards for nanotechnology. Among other points, they decried the loss of leadership the US has suffered in the international standards arena due partly to its outdated occupational health exposure limits.

What sparked the exchange of letters seems to be Murashov and Howard's characterization of the British Standards Institute's (BSI) occupational safety guide, which was submitted to ISO for consideration as the basis of an international safety standard. Murashov and Howard explain that the BSI document approaches the complex issue of nanomaterial complexity by creating a "grouping of nanomaterials into four hazard categories with assigned benchmark exposure levels (BEL)." They go on to characterize this approach as "the most controversial element" of the BSI document and caution against having it adopted as an ISO standard as it rests on an insufficient technical understanding of the toxicity and exposure potentials associated with engineered nanomaterials.

Fast forward to the current issue of Nature Nanotech. Hatto accuses the NIOSH scientists of having "a serious misunderstanding of the rigorous processes enshrined in the ISO/IEC Directives" if they think the BSI document can simply be converted to an ISO standard without significant input and deliberation by the international committee. He also defends the BSI document as a guidance document, not a specification, and asserts that it was presented as a work in progress. Murashov and Howard reply that prudent measures can be taken without setting exposure limits prematurely, and "note that the BSI website claims a history of 'converting' BSI standards into ISO standards."

I apologize if these articles are available only upon subscription. It is a noteworthy exchange among professionals deeply engaged in the standards world.

Big Whig History and Nano Narratives

My colleague (and nanotech course co-instructor) Cyrus Mody in the Rice History department has co-authored a very interesting piece posted at Science Progress today. He and co-author Patrick McCray of UCSB challenge the narratives and analogies used by both nanotech boosters and critics about its novelty by painting a much more complex picture of nano's place in the historical record. "Whig history" refers to a view of 18th century Whig party members who "tended to see the past as continual progress toward the then-present state of liberty and enlightenment." People in the nano community have similarly tended to view nano's history rather linearly--and simplistically.

While they make for nice bedtime reading, tidy and packaged histories do a disservice to policymakers who want to—who need to—understand how innovation actually occurs.

Good stuff, have a look.

Safety of nanomaterials: How to make science sexy

The European Project NanoSafe2, funded under Framework Programme 6, has produced a new website called NanoSMILE whose general objectives are to

1. Contribute to stimulate nanomaterial risks understanding: how to make science sexy?

2. Provide the knowledge and understanding about the potentials risks associated with the production, use and future of these products.

3. Clarify and distribute expertise on Risk Management

Here's a sample diagram from the site: