Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Some carbon nanotubes deplete beneficial microbes in certain soils

Ron Turco found that raw, non-functionalized, single-wall carbon nanotubes damage active microbiology in low-organic soils. (Purdue Agricultural Communication photo/Tom Campbell)
Ron Turco found that raw, non-functionalized, single-wall carbon nanotubes damage active microbiology in low-organic soils.

(Purdue Agricultural Communication photo/Tom Campbell)

Abstract:
Response of Soil Microorganisms to As-Produced and Functionalized Single-Wall Carbon Nanotubes (SWNTs)

Zhonghua Tong, Marianne Bischoff, Loring F. Nies, Phillip Myer, Bruce Applegate, and Ronald F. Turco

The use of single-wall carbon nanotubes (SWNTs) in manufacturing and biomedical applications is increasing at a rapid rate; however, data on the effects of a potential environmental release of the materials remain sparse. In this study, soils with either low or high organic matter contents as well as pure cultures of E. coli are challenged with either raw as-produced SWNTs (AP-SWNTs) or SWNTs functionalized with either polyethyleneglycol (PEG-SWNTs) or m-polyaminobenzene sulfonic acid (PABS-SWNTs). To mimic chronic exposure, the soil systems were challenged weekly for six weeks; microbial activities and community structures for both the prokaryote and eukaryote community were evaluated. Results show that repeated applications of AP-SWNTs can affect microbial community structures and induce minor changes in soil metabolic activity in the low organic matter systems. Toxicity of the three types of SWNTs was also assessed in liquid cultures using a bioluminescent E. coli-O157:H7 strain. Although decreases in light were detected in all treated samples, low light recovery following glucose addition in AP-SWNTs treatment and light absorption property of SWNTs particles suggest that AP-SWNTs suppressed metabolic activity of the E. coli, whereas the two functionalized SWNTs are less toxic. The metals released from the raw forms of SWNTs would not play a role in the effects seen in soil or the pure culture. We suggest that sorption to soil organic matter plays a controlling role in the soil microbiological responses to these nanomaterials.

Some carbon nanotubes deplete beneficial microbes in certain soils

West Lafayette, IN | Posted on January 24th, 2013

Some types of carbon nanotubes used for strengthening plastics and other materials may have an adverse effect on soil microbiology and soil microbial processes, a Purdue University study shows.

Specifically, these raw, non-functionalized single-walled carbon nanotubes were shown to damage the active microbiology in low-organic soil. Ron Turco, a professor of agronomy, said many of the bacteria affected could be involved in carbon and nitrogen cycling, which are critical processes to ensure a fully functional soil.

"There appears to be more negative potential on the active microbial population than we thought," said Turco, whose findings were published in the journal Environmental Science & Technology. "The as-produced materials could be a negative environmental situation if they are released into low-organic soils that could not absorb them."

Functionalized carbon nanotubes have modifications that create chemical or biological changes to the nanotubes. They're often used in medicines, and Turco's research showed they had no effect in high-organic or low-organic soils.

Non-functionalized single-walled nanotubes - those lacking intentional surface alterations - are being added to a variety of products during manufacturing because they can strengthen the material without adding much weight. Nanotubes contained in manufacturing waste products may find their way into wastewater treatment plants and bio-solids that result from water purification. Those bio-solids cannot be released into water, so they are often discarded by spreading on land, adding critically needed plant nutrients to soil.

"Land application of biosolids is standard procedure now," Turco said. "If any of that contains nanotubes, that could be a problem."

Single-walled nanotubes also didn't affect microbes in high-organic soils, Turco said, likely because organic materials are highly reactive. Organic materials may have reacted with the nanotubes, leaving them unable to affect microbes.

"We want to alert people to the fact that if you're going to apply these as part of a land-treatment program, you may want to focus on high-organic matter soils," he said.

It's also possible, though much less likely, that nanotubes could contaminate soil through accidental spills during a delivery, Turco said.

Next, Turco said he would look at the effects on plants and soils from other nanomaterials and nanometals that are being more widely used in products for different properties they convey, such as nanosilver for its disinfecting properties and nanoindium, which is used in electronics.

The National Science Foundation and the U.S. Environmental Protection Agency funded the research.

####

For more information, please click here

Contacts:
Writer:
Brian Wallheimer
765-496-2050


Source:
Ron Turco
765-494-8077

Copyright © Purdue University

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Measuring the Smallest Magnets July 28th, 2014

WITec to host the 11th Confocal Raman Imaging Symposium from September 29th - October 1st in Ulm, Germany July 28th, 2014

FEI adds Phase Plate Technology and Titan Halo TEM to its Structural Biology Product Portfolio: New solutions provide the high-quality imaging and contrast necessary to analyze the 3D structure of molecules and molecular complexes July 28th, 2014

Production of Toxic Gas Sensor Based on Nanorods July 28th, 2014

Govt.-Legislation/Regulation/Funding/Policy

Seeing is bead-lieving: Rice University scientists create model 'bead-spring' chains with tunable properties July 28th, 2014

Stanford team achieves 'holy grail' of battery design: A stable lithium anode - Engineers use carbon nanospheres to protect lithium from the reactive and expansive problems that have restricted its use as an anode July 27th, 2014

New imaging agent provides better picture of the gut July 25th, 2014

A*STAR and industry form S$200M semiconductor R&D July 25th, 2014

Nanotubes/Buckyballs

UCF Nanotech Spinout Developing Revolutionary Battery Technology: Power the Next Generation of Electronics with Carbon July 23rd, 2014

University of Houston researchers create new method to draw molecules from live cells: Technique using magnetic nanomaterials offers promise for diagnosis, gene therapy July 17th, 2014

3-D nanostructure could benefit nanoelectronics, gas storage: Rice U. researchers predict functional advantages of 3-D boron nitride July 15th, 2014

Researchers discover boron 'buckyball' July 14th, 2014

Discoveries

Seeing is bead-lieving: Rice University scientists create model 'bead-spring' chains with tunable properties July 28th, 2014

Measuring the Smallest Magnets July 28th, 2014

Production of Toxic Gas Sensor Based on Nanorods July 28th, 2014

Stanford team achieves 'holy grail' of battery design: A stable lithium anode - Engineers use carbon nanospheres to protect lithium from the reactive and expansive problems that have restricted its use as an anode July 27th, 2014

Announcements

Measuring the Smallest Magnets July 28th, 2014

WITec to host the 11th Confocal Raman Imaging Symposium from September 29th - October 1st in Ulm, Germany July 28th, 2014

FEI adds Phase Plate Technology and Titan Halo TEM to its Structural Biology Product Portfolio: New solutions provide the high-quality imaging and contrast necessary to analyze the 3D structure of molecules and molecular complexes July 28th, 2014

Production of Toxic Gas Sensor Based on Nanorods July 28th, 2014

Food/Agriculture/Supplements

Iranian Scientists Produce Reusable Nanoadsorbent to Detect Sulfamide in Chicken July 27th, 2014

Key Announcements made at TAPPI International Nanotechnology Conference July 7th, 2014

Squid sucker ring teeth material could aid reconstructive surgery, serve as eco-packaging July 2nd, 2014

FDA issues guidance on use of nanotechnology in foods July 1st, 2014

Environment

Production of Toxic Gas Sensor Based on Nanorods July 28th, 2014

Researchers Use Various Zinc Oxide Nanostructures to Boost Efficiency of Water Purification Process July 13th, 2014

Using Sand to Improve Battery Performance: Researchers develop low cost, environmentally friendly way to produce sand-based lithium ion batteries that outperform standard by three times July 8th, 2014

Development of an interactive tool for the implementation of environmental legislation for nanoparticles manufacturers July 4th, 2014

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More














ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE