A research team at the University of Minnesota in USA found antibiotics in plants. The root of the problem was in the soil: manure from animals that were administered antibiotics.

The plants tested included tomato, lettuce and potato. Given this, says the research team led by Satish Gupta, a shift to organic farming in the US involves risks. But in countries like India, the switch could be easier.

In India fewer livestock is given antibiotics, Gupta says. At temperatures above 40^oC, antibiotics may degrade faster, Gupta says, adding: "If manure is left in soil for long periods, it is likely that some of the antibiotics will degrade and will not be taken up by plants.' Some antibiotics, however, may persist and get absorbed by plants even when use of contaminated manure is stopped.

The paper, published in the July-August 2007 issue of the Journal of Environmental Quality, is part of a project on whether or not antibiotic use