Behavior modification could ease concerns about nanoparticles

December 16, 2009
Sewage treatment plants serve as the main gateway for nanoparticles to enter the environment. Credit: Wikimedia Commons

In an advance that could help ease health and environmental concerns about the emerging nanotechnology industry, scientists are reporting development of technology for changing the behavior of nanoparticles in municipal sewage treatment plants — their main gateway into the environment. Their study was published in ACS' journal Environmental Science & Technology.

Helen Jarvie from the UK Centre for Ecology and Hydrology and colleagues note that experts predict large increases in the production of — particles less than 1/1000th the width of a human hair — in the next decade. Manufacturers already use 2 million tons of nanoparticles each year in foods, cosmetics, medicines, and other consumer products. Studies have hinted that some nanoparticles could have adverse environmental health effects. Water discharged from sewage treatment plants is the major gateway for spread of nanoparticles to the aquatic environment. Scientists thus are focusing on how nanoparticles behave in wastewater and how that gateway might be closed off.

The study simulated (primary) sewage treatment to show that coating silica nanoparticles (similar to those used in ointments, toothpaste and household cleaners) with a detergent-like material made the nanoparticles clump together into the solid residue termed sewage sludge. Sludge often is stored in landfills or recycled as agricultural fertilizer. Uncoated nanoparticles, in contrast, stayed in the water and therefore remained in the effluent stream.

As the nanoparticles are simply too small to be visualized optically, the team used neutron scattering (at the UK's ISIS Facility) to view the sewage at the nano scale. The neutrons easily penetrate the sewage 'soup' and scatter strongly from the nanoparticles, allowing their aggregation behavior to be followed with time. The study demonstrates the potential for coating or otherwise changing the surface chemistry of nanoparticles to re-route their journey through plants, the scientists say.

Explore further: Study: Drugs from sewage not dangerous

More information: "Fate of Silica Nanoparticles in Simulated Primary Wastewater Treatment", Environmental Science & Technology, pubs.acs.org/doi/full/10.1021/es901399q

Related Stories

Study: Drugs from sewage not dangerous

July 14, 2006

A Canadian study has suggested adverse effects are unlikely on aquatic life from drugs passed through human waste released from sewage treatment plants.

Behavior modification could ease concerns about nanoparticles

November 12, 2009

In an advance that could help ease health and environmental concerns about the emerging nanotechnology industry, scientists are reporting development of technology for changing the behavior of nanoparticles in municipal sewage ...

Recommended for you

Making nanowires from protein and DNA

September 3, 2015

The ability to custom design biological materials such as protein and DNA opens up technological possibilities that were unimaginable just a few decades ago. For example, synthetic structures made of DNA could one day be ...

Graphene made superconductive by doping with lithium atoms

September 2, 2015

(Phys.org)—A team of researchers from Germany and Canada has found a way to make graphene superconductive—by doping it with lithium atoms. In their paper they have uploaded to the preprint server arXiv, the team describes ...

For 2-D boron, it's all about that base

September 2, 2015

Rice University scientists have theoretically determined that the properties of atom-thick sheets of boron depend on where those atoms land.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.