Most would probably just assume the food they buy at the grocery store is clean, not contaminated and safe to consume. But this assumption may no longer be a safe one. A recent laboratory testing has found widespread contamination from the world’s first commercially planted genetically engineered tree. Papaya contamination has been detected on O’ahu, the Big Island and Kaua’i, along with contamination in non-genetically engineered seeds sold commercially by the University of Hawai’i.

Then, last spring, some of Mr. Lahti’s fruit tested positive for genetically modified seeds. »’I was really surprised,’« Mr. Lahti said. »’I didn’t really know what was happening.”

He cut down all 170 of his trees and is now replanting, without any guarantee that the same problem - pollen from modified trees on other farms drifting on the wind to pollinate his trees - won’t happen again. From papayas in Hawaii, to corn in Mexico and canola in Canada, the spread of pollen or seeds from genetically engineered plants is evolving from an abstract scientific worry into a significant practical problem.

Pollen from genetically engineered papayas has contaminated at least some ordinary papaya plants in Hawaii, say advocates for controls on genetically modified organisms. Evidence of such »genetic drift« with papaya was recently confirmed with testing of Hawaii papaya samples at a mainland lab, representatives of Hawaii Genetic Engineering Action Network and GMO-Free Hawaii said Thursday. Proponents of the genetically engineered Rainbow and SunUp papayas agreed that pollen can spread to nonengineered trees, but said they would need to know more about testing methodologies before agreeing there is a problem.

Dr. Richard Meagher, a professor of genetics at the University of Georgia, genetically engineered the trees to extract mercury from the soil, store it without being harmed, convert it to a less toxic form of mercury and release it into the air. It was one of two dozen proposals Dr. Meagher has submitted to various agencies over two decades for engineering trees to soak up chemicals from contaminated soil. For years, no one would pay him to try. »I got called a charlatan,« he said. »People didn’t believe a plant could do this.« He will begin to assess the experiment’s success this fall. But his is not the only such experiment with trees.

Global Justice Ecology Project and the Stop GE Trees Campaign, both based in the U.S., are working with organizations including The Corner House of the UK, The Union of Ecoforestry from Finland, and World Rainforest Movement of Uruguay, to pressure the United Nations to oppose the use of genetically engineered trees in carbon offset forestry plantations developed under the Kyoto Protocol, and to ban their commercial development. On 11 May petitions signed by renowned scientists such as Dr. David Suzuki, more than 160 organizations including The Sierra Club, and Friends of the Earth International as well as over 1,500 individuals will be presented to the U.N. in Geneva backing these demands.

Can genetically engineered cottonwood trees clean up a site contaminated with toxic mercury? A team of researchers from the University of Georgia - in the first such field test ever done with trees - is about to find out.

The results could make clearer the future of phytoremediation - a technique of using trees, grasses and other plants to remove hazardous materials from the soil. [...] We hope to see a significant difference in the levels of mercury in the soil within 18 months, perhaps as much as a twofold reduction,« said Richard Meagher, professor of genetics at UGA.

It’s a kind of Superfund superplant, a leafy organism designed specifically to devour the hazardous waste that industrial machinations and human carelessness have left in the ground. The genetically modified mutant plants suck heavy metals, such as lead and arsenic, out of the soil into their roots, stems and leaves, cleansing the contaminated soil. It’s an intoxicating vision: Imagine fields of these valiant plants fighting part of the $700 billion battle that the United States faces in mopping up polluted Superfund sites.

Scientists are planting genetically engineered trees in dozens of research projects across the country, ignoring the pleas of environmentalists who fear dangerous, unintended consequences. When we’re talking about changing the very makeup of wild forests, we definitely need to apply caution,«said Kathleen Casey, with the Northwest office of the Sierra Club. Trees send their pollen huge distances, and the idea that this won’t contaminate the gene pool is ridiculous,«said Phil Bereano, a University of Washington professor of engineering.

Can biotechnology save the planet? When most people hear that question, they probably think about genetically modified food or new drugs. But the same technologies that are being developed for farms and pharmaceuticals have scientists speculating that biotechnology could hold some promise for moderating global warming caused by the greenhouse effect.

The expensive, energy-intensive process of turning wood into paper costs the pulp and paper industries more than $6 billion a year. Much of that expense involves separating wood’s cellulose from lignin, the glue that binds a tree’s fibers, by using an alkali solution and high temperatures and pressures. Although the lignin so removed is reused as fuel, wood with less lignin and more cellulose would save the industry millions of dollars a year in processing and chemical costs. [...] By genetically modifying aspen trees, Dr. Vincent L. Chiang, professor of forest biotechnology, and his colleagues have reduced the trees’ lignin content by 45 to 50 percent - and accomplished the first successful dual-gene alteration in forestry science.