NANOTECHNOLOGY

Nanotechnology, or tiny tech, uses science and engineering to manipulate and create materials out of atoms and molecules at the ultra-small scale of less than 100 nanometers. A nanometer equals one billionth of a meter. It is one hundred-thousandth the width of a human hair, and the period at the end of this sentence is about 1 million nanometers in diameter. At the nanoscale level, conventional materials have unconventional and unexpected properties. Scientists plan to use atoms of abundant substances such as carbon, silicon, silver, titanium, and boron as building blocks to create everything from medicines and solar cells to automobile bodies. Nanomaterials are currently used in more than 800 consumer products and the number is growing rapidly. Such products include stain-resistant and wrinkle free coatings on clothes, odor-eating socks, self-cleaning coatings on sunglasses and windshields, sunscreens, deep-penetrating skin care products, and food containers that release nanosilver ions to kill bacteria, molds, and fungi. green career: environmental nanotechnology Nanotechnologists envision innovations such as a supercomputer the size of a sugar cube that could store all the information now found in the U.S. Library of Congress; biocomposite particles smaller than a human cell that would make our bones and tendons super strong; nanovessels filled with medicines and delivered to cells anywhere in the body; and nanomolecules specifically designed to seek out and kill cancer cells. We could also use nanoparticles to remove industrial pollutants in contaminated air, soil, and groundwater, and we might be able to purify water and desalinate water at an affordable cost with nanofilters. We could also use the technology to turn garbage into breakfast by mimicking how nature turns wastes into plant nutrients, thus following the chemical cycling principle of sustainability. The list could go on. So what is the catch? Ideally, this bottom-up manufacturing process would occur with little environmental harm, with no depletion of nonrenewable resources, and with many potential environmental benefits. But there are concerns over some possible unintended and harmful health effects on humans, because a few studies have raised red flags. As particles get smaller, they become more reactive and potentially more toxic to humans and other animals. Laboratory studies show that nanoparticles can move across the placenta from mother to fetus and from the nasal passage to the brain. They might also penetrate deeply into the lungs, be absorbed into the bloodstream, and penetrate cell membranes. A British animal study found that certain carbon nanotubes could damage lungs in the same way that asbestos does. A study done in Singapore showed that nanosilver particles severely disrupted development in zebra fish embryos. In addition, scientists note that such damage in humans could take years or decades to become apparent. Many analysts say we need to take two steps before unleashing nanotechnology more broadly. First, carefully investigate its potential risks. Second, develop guidelines and regulations for controlling its growing applications until we know more about the potentially harmful effects of this new technology. So far, governments have done little to evaluate and regulate such risks. In 2009, an expert panel of the U.S. National Academy of Sciences said that the federal government was not doing enough to evaluate the potential health and environmental risks from engineered nanomaterials.