It’s that time of year when just about everybody seems to be on holidays and finding material to post about becomes harder than usual. Consequently, I dug through some of my backfiles to find this piece on mesocosms and Duke University from November 2010.
From the article, Ecosystem experiments to assess the environmental impact of nanoparticles, by Whitney J. Howell published November 25, 2010 on Nanowerk,
Deep inside Duke Forest, 32 alternate universes sit in quiet rows. They look identical – each with a puddle, some land, a few plants.
But wholly imperceptible to the naked eye, these plots have distinct and important differences.
The realms, known as mesocosms, house individual types of nanoparticles as part of a research effort conducted by the Center for the Environmental Implications of Nano Technology (CEINT) based at Duke University.
The mesocosms are (from the CEINT Mesocosm Construction page) “3ft x 12ft [constructed environments] where researchers can add nanoparticles [to study interactions] and effects on plants, fish, bacteria, and other elements within these contained systems.”
According to Howell’s article (originally published in the Raleigh News & Observer), the mesocosm project at Duke should be winding up shortly,
To track where and at what levels the environment absorbs nanoparticles, CEINT began the yearlong mesocosm project in August . The findings will also reveal the effects of nanoparticle presence.
Each waist-high, 3-foot-by-12-foot box contains nanoparticles coated with a different substance, such as titanium dioxide or silver. By following the coating’s trail through the mesocosm, Wiesner said, researchers can pinpoint how the nanoparticles either positively or negatively alter their surroundings and at what levels they might become toxic.
For example, nanosilver has anti-microbial properties and could be a powerful disinfectant. But if high concentrations of the particles wipe out all surrounding bacteria and viruses – even those that may be benign or beneficial – the effects on plants and animals is unknown.
The Duke investigators are monitoring the mesocosm changes as nanosilver and other nanoparticle levels increase, hoping to identify which substances are most harmful to the environment and humans, and at what level they become worrisome.
CEINT’s external advisory board features Dr. Andrew Maynard, Director of the University of Michigan Risk Science Center (and mentioned here fairly frequently due to his longstanding expertise on nanotechnology [he was formerly the Chief Science Advisor for the Project on Emerging Nanotechnologies based in Washington, DC]).
They’ve been busy at the CEINT, here’s where you can find a list of publications by the staff, including blockbusters such as,
Shoults-Wilson, WA, Zhurbich OI, McNear DH, Tsyusko OV, Bertsch PM, Unrine JM. 2011. Evidence for avoidance of Ag [silver] nanoparticles by earthworms (Eisenia fetida). Ecotoxicology. 20:385-96. Abstract
Chae, SR, Hotze EM, Xiao Y, Rose J, Wiesner MR. 2010. Comparison of Methods for Fullerene Detection and Measurements of Reactive Oxygen Production in Cosmetic Products. Environmental Engineering Science. 27:797-804. Abstract
You can find more of Whitney Howell’s work here.