HOME  |  NEWS  |  BLOGS  |  MESSAGES  |  FEATURES  |  VIDEOS  |  WEBINARS  |  INDUSTRIES  |  FOCUS ON FUNDAMENTALS
  |  REGISTER  |  LOGIN  |  HELP
Blogs
Engineering Materials

Just How Toxic Are Carbon Nanotubes?

NO RATINGS
View Comments: Oldest First|Newest First|Threaded View
<<  <  Page 2/4  >  >>
sbkenn
User Rank
Gold
Re: Toxic? carbon nanotubes
sbkenn   12/1/2012 1:29:19 PM
NO RATINGS
I believe that CNN's do occur naturally, as in Damascus Steel of the Medieval to mid 1800's, when the iron ore mines(thought to have been in Kerala in India) were cleaned out.

William K.
User Rank
Platinum
Carbon nanotubes
William K.   12/1/2012 3:56:12 PM
NO RATINGS
Damascus steel is certainly some impressive stuff, but my understanding is that it is created through a great deal of work, bonding and folding and rebonding to get steel with alternating layers of hard and tough steel. Definitely not a naturally occurring material. Free lead, nickle, cadmium, and copper all occur in their free state and can be found naturally. Likewise asbestos, although it is usually in with mica, I think.

Of course heating to ignition with microwaves would be an effective means of disposal for CNT waste, but first it would need to be located. That is probably going to be the challenge if quantities of CNT material are spilled.

etmax
User Rank
Gold
Re: Toxic? carbon nanotubes
etmax   12/2/2012 10:36:25 PM
NO RATINGS
Are you sure it was carbon in Damascus steel?? I thought it was cobalt or something like that?

Ann R. Thryft
User Rank
Blogger
Re: life cycle concerns
Ann R. Thryft   12/3/2012 11:56:44 AM
NO RATINGS
Lou, thanks for your comments. Researching and writing this article made me think how, for the nth time, we've gone off looking for new technologies without first considering whether the (new or old) materials involved are harmful to living beings when introduced into the ecosystem, or even how likely it is that the materials can easily get into the ecosystem. It's simply not one of the first questions we ask--and I think it should be.

Dave Palmer
User Rank
Platinum
Re: Toxic? carbon nanotubes
Dave Palmer   12/3/2012 2:35:47 PM
NO RATINGS
A German research group published an article in Nature in 2006 showing that a Damascus blade produced in the 17th century contained multi-walled carbon nanotubes, as well as cementite nanowires.  It's believed that the nanotubes formed in-situ during the forging process.  You can read the article here.

The article mentions that cobalt, along with other alloying elements present in small amounts, played an important role in providing the steel with its distinctive microstructure.

Dave Palmer
User Rank
Platinum
Re: life cycle concerns
Dave Palmer   12/3/2012 2:41:32 PM
NO RATINGS
@Ann: You're definitely right that environmental and health impacts should be at the front of our minds when evaluating a new material.  That being said, there has been a lot of work done on the toxicity of nanomaterials, particularly over the past 5-7 years. A lot of people are working on this, to ensure that we aren't opening Pandora's box.

Ann R. Thryft
User Rank
Blogger
Re: life cycle concerns
Ann R. Thryft   12/3/2012 3:01:30 PM
NO RATINGS
Tim and ervin0072002, based on the Japanese, US and European concerns about CNTs from all sources, which we covered here
http://www.designnews.com/document.asp?doc_id=237995
and especially during the manufacturing process, I think the answer to Tim's question is "yes."

Cabe Atwell
User Rank
Blogger
Re: life cycle concerns
Cabe Atwell   12/3/2012 4:38:16 PM
NO RATINGS
Great, one of the future super-materials is poised to kill us all. I suppose silicon has been killing life for decades directly and indirectly. What else is new. Perhaps the study should look at how the nano-tube compares to the material it is replacing. I'm sure as materials like this become commercialized, they will.

C

Dave Palmer
User Rank
Platinum
Re: life cycle concerns
Dave Palmer   12/4/2012 10:43:19 AM
NO RATINGS
@Cabe: Obviously everything has risks, but it's important to understand the risks, so that you can keep them under control.  There are three Superfund sites within walking distance of my house.  One is a former Johns Manville insulation plant that once employed 6500 people. It is still contaminated with more than 3 million cubic yards of asbestos.  Another is our harbor, which is contaminated with PCBs that were used in a former die casting facility that employed more than 4000 people.  Not only are the jobs gone, but we're left with the mess and its long-term effects.  This is why it's important to understand the health and environmental implications of a material before employing it on a mass scale.



Ann R. Thryft
User Rank
Blogger
Re: life cycle concerns
Ann R. Thryft   12/4/2012 11:48:39 AM
NO RATINGS
Dave, thanks for the info and links, and the perspective of one directly affected by environmental toxicity. Cabe, the toxicity potential is far, far worse with nanomaterials than with materials that have micro-sized particles, such as silicon. It's a matter of scale, for one thing: in this case, size matters enormously (pun intended). You might want to take a look at some of the background material, such as the links Dave provided or those in my previous nanomaterial legislation article, to understand how different events at the nanoscale can be from events at the microscale. It's an eye-opener.

<<  <  Page 2/4  >  >>
Partner Zone
More Blogs from Engineering Materials
The amount of plastic clogging the ocean continues to grow. Some startling, not-so-good news has come out recently about the roles plastic is playing in the ocean, as well as more heartening news about efforts to collect and reuse it.
Optomec's third America Makes project for metal 3D printing teams the LENS process company with GE Aviation, Lockheed, and other big aerospace names to develop guidelines for repairing high-value flight-critical Air Force components.
Lots of people who write about robots say they give us jobs, instead of taking them away from humans. Based on the evidence in some recent studies, I'm not so sure.
A self-propelled robot developed by a team of researchers headed by MIT promises to detect leaks quickly and accurately in gas pipelines, eliminating the likelihood of dangerous explosions. The robot may also be useful in water and petroleum pipe leak detection.
Aerojet Rocketdyne has built and successfully hot-fire tested an entire 3D-printed rocket engine. In other news, NASA's 3D-printed rocket engine injectors survived tests generating a record 20,000 pounds of thrust. Some performed equally well or better than welded parts.
Design News Webinar Series
7/23/2014 11:00 a.m. California / 2:00 p.m. New York
7/17/2014 11:00 a.m. California / 2:00 p.m. New York
6/25/2014 11:00 a.m. California / 2:00 p.m. New York
5/13/2014 10:00 a.m. California / 1:00 p.m. New York / 6:00 p.m. London
Quick Poll
The Continuing Education Center offers engineers an entirely new way to get the education they need to formulate next-generation solutions.
Aug 4 - 8, Introduction to Linux Device Drivers
SEMESTERS: 1  |  2  |  3  |  4  |  5  |  6


Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.
Next Class: August 12 - 14
Sponsored by igus
Learn More   |   Login   |   Archived Classes
Twitter Feed
Design News Twitter Feed
Like Us on Facebook

Sponsored Content

Technology Marketplace

Copyright © 2014 UBM Canon, A UBM company, All rights reserved. Privacy Policy | Terms of Service