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Nanotechnology is a fashionable word these days. The name “nano”(纳米) comes from the size of molecules, which are measured in nanometers—or one billionth of a metre. Through operating the atoms and molecules, scientists can change the nature of common materials and even create new materials that have new properties.
But scientists are concerned about its possible risks to our daily lives.
Clothing merchants claim their nano—cloth keeps our bodies warmer in winter, saving us from needing thick coats. Vitamin companies boast their nano—pills are easier to absorb. Home decoration companies suggest you use their nano—paint, which has no smell, is waterproof, and free from poisonous substances.
Nanomaterials are making our lives better, its creators say. The US National Science Foundation predicts nanotechnology research will grow into a US $-trillion industry over the next 10 years.
But relatively little is known about the potential health and environmental effects of the tiny particles. Just atoms wide, they are small enough to penetrate cells easily in lungs, brains and other organs. US best—seller “Prey”, written by Michael Crichton, paints a doomsday in which a group of tiny nanomachines escapes the lab and threatens to take control of humanity.
Studies have shown that some nanoparticles can be...