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.

會抽煙的植物

人們驚訝地發(fā)現植物也會成為被動吸煙者，它們會呼入燃燒煙草釋放的煙霧、尼古丁以及其他污染物。與綠色植物共享環(huán)境，人們可以擁有更舒適的空氣環(huán)境。但是，人們食用的植物是否也會吸入污染物呢？一項新的研究發(fā)現，答案是肯定的。研究者指出，某些草藥茶中發(fā)現的尼古丁就緣于此。

德國布倫瑞克工業(yè)大學的一個研究團隊最近研究了一種名為“胡椒薄荷”的植物，他們用11支燃燒的香煙散發(fā)出來的煙來熏幾盆胡椒薄荷。研究者報告：兩小時之內，胡椒薄荷的葉片沾染了含量極高的尼古丁。甚至在胡椒薄荷遭遇香煙噴熏8天之后，葉子中的尼古丁含量也只下降了一半。

但是，空氣并不是植物接觸尼古丁的唯一媒介物，植物的根也從土壤中吸收污染物。比如，研究者將100毫克的煙草（相當于一支香煙中1/8至1/10的含量）噴灑在植物生長的泥土里。9天后，胡椒薄荷的老葉子（噴灑時已經長出的葉子）中的尼古丁含量大約是其他未經如此處理的植物葉子中的5倍。

“從食品安全的角度看，我們沒有必要恐慌。”該研究團隊指出。他們做這項研究的意圖，是為了解釋某些草藥茶和香料中為何會意外含有尼古丁。通過研究，他們得出結論：在種植、加工草藥茶和香料的過程中，抽煙的農民和加工者在一定程度上至少會給產品染上尼古丁。

（注意斜體字的譯法）