Smoking's Atonishingly Unintended Consequence

Passive smoking isn't only something that people have to cope with, but plants too. This is because some plants are actually able to take up nicotine from cigarette smoke, while others that grow in contaminated soil absorb it via the roots as well. This might explain why high concentrations of nicotine are often found in spices, herbal teas and medicinal plants, despite the fact that this alkaloid is no longer permitted in insecticides. The findings are published in Agronomy for Sustainable Development.

They used peppermint plants, which contain minimal traces of nicotine, in a series of mulching and fumigation experiments. Tremendously elevated nicotine levels were detected after fumigation with cigarette smoke. Peppermint plants can also take up high concentrations of nicotine from contaminated soils evidenced after mulching with cigarette tobacco for more than nine days. The resulting nicotine concentrations were several times higher than the maximum residue levels.

Steve: In addition to the significance for the food industry, these results have a tremendous relevance for basic science: they prove that substances, such as alkaloids, can be transferred from one plant, after its death, to another. Such "horizontal transfer of natural products" sheds light on the unexplained success behind farming practices such as crop rotation and the co-cultivation of certain vegetables. It also shows how intricate and intelligent plants are.