美国科学60秒 SSS 2012-12-17
时间：2018-12-24 作者：英语课 分类：Scientific American(十二)月
英语课
This Scientific American’s podcast is sponsored by audible.com, the number-one online resource for best-selling audio books and more. And now audible.com is offering Scientific American listeners a free audio book of your choice. For details go to audible.com/sciam.
Onions and garlic add pizzazz to your cooking. But they can also do a more distasteful job: onions and garlic can suck heavy metals from industrial wastewater. So finds a study in the International Journal of Environment and Pollution.
Good recipes start with the right ingredients. So Indian researchers rounded up onion and garlic peels from the canning industry, and dried and powdered them. They got industrial runoff from an electric motor factory in Delhi, laced with pollutants 1 like arsenic 2, iron, lead, nickel and tin. They spiked 3 that runoff with even more heavy metals. And then added a pinch of onion powder.
In just half an hour, the onion gunk mopped up nearly 70 percent of the lead, iron and tin in the wastewater. It might work because onions and garlic contain a dietary fiber 4 called inulin, which can bond with metal ions.
Conventional wastewater treatment is pricey - small industries in developing countries can't afford it. So low-tech solutions like this might help clean up waterways like India's Yamuna River - a waterway so polluted that it might be freshened by onions and garlic.
1 pollutants
污染物质（尤指工业废物）( pollutant的名词复数 )
- Pollutants are constantly being released into the atmosphere. 污染物质正在不断地被排放到大气中去。
- The 1987 Amendments limit 301(g) discharges to a few well-studied nonconventional pollutants. 1987年的修正案把第301条（g）的普通排放限制施加在一些认真研究过的几种非常规污染物上。 来自英汉非文学 - 环境法 - 环境法
