Pressure-treated lumber is generally safe, but chemicals can leach out. Michigan Tech researchers are using nanotechnology to keep the chemicals inside, where they can do no harm to the environment. |
Pressure-treated
wood is great stuff, but the chemicals used to preserve it from decay
can leach out, where they can be toxic to bugs, fungi and other hapless
creatures that have the bad luck to be in the neighborhood. Now, a team
of Michigan Technological University scientists has used nanotechnology
to keep the chemicals inside the wood where they belong.
“It’s
a new method that uses nanoparticles to deliver preservatives into the
lumber,” said chemistry professor Patricia Heiden. “In our experiments,
it reduced the leaching of biocides by 90%.”
The
nanoparticles are tiny spheres of gelatin or chitosan (a material found
in the shells of shrimp and other shellfish) chemically modified to
surround the fungicide tebuconazole. The little spheres require no
special handling.
“You just pressure-treat the wood in the usual way,” Heiden said.
The
initial tests show that the nanoparticle-treated wood is just as
resistant to rot and insects as conventionally treated lumber. The
researchers are now testing the wood in the warm, wet weather of Hawaii.
The
research is funded by the US Environmental Protection Agency. Also
contributing to the project are chemistry PhD student Xiaochu Ding and,
from the School of Forest Research and Environmental Science, Research
Engineer/Scientist II Dana Richter, Senior Research Engineer/Scientist
Glenn Larkin, Assistant Research Scientist Erik Keranen and Professor
Peter Laks.