Smokin" Plants

Smokin' Plants

Plants turn out to be secondhand smokers. They breathe in smoke， nicotine and other pollutants released by burning tobacco. By sharing our environment with green plants， people may be able to breathe easier. But can plants that people eat also suck up pollutants？ Yes， a new study finds. And that may explain why nicotine has been found in some herbal teas， its authors note.

A research team which works at the Technical University of Braunschweig， Germany， recently decided to work with peppermint plants. They trapped pots of them with fumes from 11 smoked cigarettes. Within two hours， peppermint leaves had picked up a "tremendously" high amount of nicotine， the researchers now report. Even eight days after the plants encountered the cigarette smoke， their leaves' spike in nicotine had dropped by only half.

But air is not the only route by which plants can become exposed to nicotine. Roots can also take up the pollutant from soil. For instance， the researchers sprinkled 100 milligrams of tobacco-about an eighth to a tenth of what would be in a cigarette-onto the ground in which plants were growing. Nine days later， the plants' older peppermint leaves had roughly five times as much nicotine as did those in untreated plants.

"From a food safety point of view， there is no reason to panic，" the research team says. They intended the research to help explain unexpected amounts of nicotine in some herbal teas and spices. Smoking farmers and processors could contribute， at least somewhat， to the bonus nicotine， they concludes.

会抽烟的植物

人们惊讶地发现植物也会成为被动吸烟者，它们会呼入燃烧烟草释放的烟雾、尼古丁以及其他污染物。与绿色植物共享环境，人们可以拥有更舒适的空气环境。但是，人们食用的植物是否也会吸入污染物呢？一项新的研究发现，答案是肯定的。研究者指出，某些草药茶中发现的尼古丁就缘于此。

德国布伦瑞克工业大学的一个研究团队最近研究了一种名为“胡椒薄荷”的植物，他们用11支燃烧的香烟散发出来的烟来熏几盆胡椒薄荷。研究者报告：两小时之内，胡椒薄荷的叶片沾染了含量极高的尼古丁。甚至在胡椒薄荷遭遇香烟喷熏8天之后，叶子中的尼古丁含量也只下降了一半。

但是，空气并不是植物接触尼古丁的唯一媒介物，植物的根也从土壤中吸收污染物。比如，研究者将100毫克的烟草（相当于一支香烟中1/8至1/10的含量）喷洒在植物生长的泥土里。9天后，胡椒薄荷的老叶子（喷洒时已经长出的叶子）中的尼古丁含量大约是其他未经如此处理的植物叶子中的5倍。

“从食品安全的角度看，我们没有必要恐慌。”该研究团队指出。他们做这项研究的意图，是为了解释某些草药茶和香料中为何会意外含有尼古丁。通过研究，他们得出结论：在种植、加工草药茶和香料的过程中，抽烟的农民和加工者在一定程度上至少会给产品染上尼古丁。

（注意斜体字的译法）