SSS 2010-05-14(在线收听) |
This is Scientific American's 60-Second Science. I'm Cynthia Graber. This’ll just take a minute. Bisphenol A. Also called BPA, it's used to make shatter-proof plastic known as polycarbonate, found in everything from water bottles to medical devices to the lining of food packaging. As much as 2.7 million tons of plastics are manufactured each year with BPA. But it's also an endocrine disruptor posing a threat to fetuses and young children. And it’s been linked to cancer and metabolic disorders leading to obesity. So how can plastics be properly disposed of to avoid releasing BPA into the environment? Some fungus may help. So say researchers publishing in the journal Biomacromolecules. The scientists selected three fungi that are already used for environmental cleanup. They wanted to optimize conditions for the fungi to break down polycarbonate, so first they treated the plastic with ultraviolet light and heat. Untreated polycarbonate served as a control. After 12 months, the untreated plastic hadn’t decomposed at all. But the fungi had munched through the treated plastic and used it all as an energy source. Even better, the BPA had been entirely broken down as well. Tests of the sample found no BPA residue. That’s good news in the effort to mop up a persistant pollutant. Thanks for the minute for Scientific American's 60-Second Science. I'm Cynthia Graber. |
原文地址:http://www.tingroom.com/lesson/sasss/2010/5/101791.html |