Pressure-treated wood is great stuff, but the chemicals used to preserve it from decay can leach out, where they can be toxic to insects, fungi and other creatures. Now, a team of Michigan Technological University scientists has used nanotechnology to keep the chemicals inside the wood where they belong. “This is 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 percent.” The nanoparticles are tiny spheres of gelatin or chitosan chemically modified to surround the fungicide tebuconazole. No special handling is required, the wood is just pressure-treated in the usual way.