Making sure the wonder materials don't become the wonder pollutant

Carbon nanotubes are 10,000 times thinner than a human hair, yet stronger than steel and more durable than diamonds. They conduct heat and electricity with efficiency that rivals copper wires and silicon chips, with possible uses in everything from concrete and clothes to bicycle parts and electronics. The have been hailed as the next “wonder material” for what could become a multi-billion dollar manufacturing industry in the 21st century.