Nexus - 1703 - New Times Magazine-pages

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OB OY YL VEN? NANOPARTICLES CAUSE TOXICITY IN FISH PANEL CALLS FOR GLOBAL "ASTEROID DEFENCE AGENCY" if a Purdue University study, « nanosilver suspended in solution was tested on fathead minnows (an organism often used to test the effects of toxicity on aquatic life) and proved toxic and even lethal to the minnows. When the nanosilver was allowed to settle, the solution became several times less toxic but still caused malformations in the minnows. "Silver nitrate is a lot more toxic than nanosilver, but when nanosilver was sonicated, or suspended, its toxicity increased tenfold,” said Maria Septlveda, an assistant professor of forestry and natural resources whose findings have been published in Ecotoxicology {2010; 19(1):185]. "There is reason to be concerned." Using electron microscopy, Septilveda was able to detect nanosilver particles measuring 30 nanometres or less inside minnow embryos. Thirty nanometres is more than 3,000 times smaller than the diameter of a human hair. "These nanosilver particles are so US National Research Council panel has recommended setting up an international body that would be prepared to spring into action and defend the planet if an asteroid were discovered on a likely impact course. There are huge numbers of asteroids that come close to Earth's orbit, called near- Earth asteroids (NEAs). Millions of them are large enough to do serious damage in an impact, including the asteroid Apophis, which has a small chance of hitting Earth in 2036. The international body would be “composed of representatives of nations concerned with this problem and willing to invest in preparedness for a damaging collision," the panel's report states. The report also found that existing surveys are incapable of finding 90 per cent of near-Earth asteroids that are 140 metres across or larger by 2020, a goal set by Congress in 2005. (Source: New Scientist, 10 January 2010, http://tinyurl.com/yok4a3k) small they are able to cross the egg membranes and move into the fish embryos in less than a day," Septilveda said. Nanosilver is growing in popularity as a component of many products. It is used to kill bacteria in products such as odour-control clothing, countertops, cutting boards and detergents. Currently, there are few regulations for nanosilver's applications in products. (Source: ScienceDaily.com, 5 March 2010, http://tinyurl.com/ydvgvjk) a | nr 58.) 7 a DEMAND RISING IN CHINA FOR WEATHER MODIFICATION hina will step up weather modification in key regions to elp relieve drought, the director of he China Meteorological Administration has said. As drought and hailstorms pose severe threats to rural income and ‘ood supply, there is a rising demand or technology to cushion the impact, Zheng Guoguang told China Daily. Modifying weather involves seeding clouds with grains of dry ice frozen carbon dioxide) or tiny particles of silver iodide to stimulate rainfall or dissipate clouds. It is also used to help prevent or control 6 * NEXUS APRIL - MAY 2010 www.nexusmagazine.com