Plants suck in nicotine from nearby smokers

Plants turn out to be secondhand smokers, taking in nicotine from humankind’s tobacco and fumes. And lab tests suggest that slipping a cigarette butt into a plant’s pot sends a temporary surge of nicotine into its leaves.

Researchers sprinkled 100 milligrams of American Spirit tobacco — about an eighth to a tenth of a cigarette — onto the soil of potted peppermint plants. Nine days later older leaves carried roughly fivefold the background level of the leaves’ nicotine, Dirk Selmar of Technische Universität Braunschweig in Germany and his colleagues report April 7 in the journal Agronomy for Sustainable Development.

Nicotine levels spiked also in peppermints closeted with fumes from 11 cigarettes smoked in two hours.

“From a food safety point of view, there is no reason to panic,” Selmar says. He intended the research to help chase down sources of unexpected nicotine in herbal teas and spices despite the European Union’s 2009 ban on nicotine pesticides. Smoking farmers and processors could contribute, in part at least, to the rogue nicotine, Selmar concludes.