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Lowly geranium feasts on toxins: Scientists try to patent lemon-scented marvel Friday, July 16, 1999 - Researchers at the University of Guelph have applied for an international patent on lemon-scented geraniums, believing they are pollution-eating plants that could clean the environment and restore a toxic land patch to a Garden of Eden. Their research has found that the familiar flowering plant has an uncanny ability to absorb metal and organic pollutants which could help to detoxify everything from abandoned gas station sites to old mining lands. They may also be of particular benefit to developing countries whose crop yields suffer because of naturally occurring high metal content in their soils. Plant biologist Praveen Saxena and his team are now hurrying to find the genes that endow the lemon-scented geranium with its rare ability to tolerate and absorb pollutants so they might, through genetic engineering, enhance those traits. And although they have not yet discovered those genes, they have requested in the patent application filed last year that their claim include any genetically modified form of the lemon-scented geranium that would be used to detoxify the environment. Patents have been issued on other plants, Dr. Saxena said. But the issue of laying an ownership claim over a natural life form remains a controversial area of biotechnology. This is partly because critics argue that patents often make new agricultural technology unaffordable to farmers who could benefit most from it. Stephanie De Grandis, associate director of Guelph's business development office, explained that the patent would not be on the plant, but on the process of using the plant for cleaning up contaminated soil, called phytoremediation. "Anyone who went out to use these geraniums for phytoremediation would have to come and talk to us [if the patent is granted]," Dr. De Grandis said, adding that anyone who didn't could face legal action. After planting the scented geraniums in contaminated soil samples from an undisclosed site in Canada and conducting a similar trial at a contaminated Hamilton location, the researchers found that the plants cleaned up toxic soil and flourished in it. "With other methods to get rid of toxic metals in the soil, the soil is left clean, but it's useless," Dr. Saxena said. But by planting lemon-scented geraniums to clean the soil, the same land could later be used for farming, he added. Around the world, several different research groups are searching for metal-resistant genes in the few plant varieties that can thrive in metal-rich soils. Some, according to an article published today in Science, are trying to insert metal-resistant genes from other organisms, such as bacteria, into the DNA of crop plants to make transgenic plants that would be metal-resistant. Such a project is under way at the University of Sasketchewan. Metals are a key enemy of plant growth and result in stunted plants and poor harvests in the Southeastern United States, Central and South America, North Africa and parts of India and China. While some sites have natural metal contaminants, others have been polluted by industry. Wilf Keller, research director of the federal government's Plant Biotechnology Institute in Saskatoon, said a biological solution to clean up the "thousands" of contaminated sites in North America would be the most environmentally friendly option. He noted that members of the cabbage family can grow in lead-contaminated soil, and that rubber trees in the South Pacific can absorb so much nickel from the ground that their sap turns blue. But, he said, the scented geraniums -- formally known as Pelargonium sp. Frensham -- are unusual because of their absorption capabilities and their ability to turn contaminated soil into arable land. "I think this research has to be treated as a significant invention . . . or a discovery. It will offer significant improvements for the environment," Dr. Keller said. He acknowledged that there is always the possibility for debate about the legitimacy of a proprietary patent over the biological function of a plant as an "invention." But he noted that the researchers discovered the plant's environmental usefulness. The University of Guelph researchers suspect that scented geraniums may be the only known plant species that has the ability to absorb both multi-metal and organic chemical contaminants, anything from cadmium to hydrocarbons. Dr. Saxena has reported that the geraniums can soak up as much as 3,300 milligrams of cadmium, 18,700 mg of lead, 6,400 mg of nickel and 650 mg of copper for every kilogram of plant tissue in two weeks. The plants do not exhibit any sign of toxic stress. Carolyn Abraham The Globe and Mail <http://www.GlobeandMail.ca/gam/Science/19990716/UPLANN.html> janet paterson 52 now / 41 dx / 37 onset snail-mail: PO Box 171 Almonte Ontario K0A 1A0 Canada website: a new voice <http://www.geocities.com/SoHo/Village/6263/> e-mail: <[log in to unmask]>