 Global Connections
with David Suzuki
Crop this
While debate over the benefits and dangers of genetically modified crops may have quieted down, studies are continuing on the effects these crops might have on the natural world. Recently, the last of a series of British "farm-scale" evaluations was completed. And once again, genetically modified crops didn't come off very well.
The farm-scale evaluations conducted in England over the past several years are considered to be the world's largest ecological experiment on how new farming practices can affect nature. The first of these studies, published in 2003, looked at sugar beets, spring oilseed rape (canola), and maize (corn). It reported that, while transgenic corn faired better than its conventional counterpart in its effect on the environment, both the spring canola and the sugar beets fared worse.
For the latest study, researchers looked at conventional winter canola and compared it to its transgenic variety. In this case, the transgenic plants had been modified to resist a specific herbicide - allowing farmers to spray their fields liberally and kill weeds without harming their crop.
However, the herbicide is especially effective at killing broadleaf weeds, which are also preferred by bees and butterflies. Researchers found that, as a result, butterfly populations dropped by up to two thirds in the transgenic fields and bee populations dropped by one-half. Some biologists are concerned about the long-term impact this could have on biodiversity in Britain and on creatures, like birds, further up the food chain, if the crop were grown on a large scale.
While these findings are certainly not a death knell for transgenic crops, it shows that tinkering with the genes of an organism can have repercussions far beyond the "minor" modification intended by biotech scientists. That's because the scientists focus on controlled tests done in a lab or growth chamber, but that's not the real world where there are birds, insects, rain and wind, which complicates things. The British study also shows that we must proceed cautiously with all transgenic crops. Every modification could have profound repercussions to the natural world and should be tested thoroughly, both in controlled situations and in field evaluations before wide release.
Right now in North America, genetically modified crops are treated just like their conventional counterparts. They are considered "substantially equivalent" and thus not subject to any special regulations.
Companies that make transgenic plants insist that their crops are strictly monitored and have not caused any problems. But just recently it was found that Syngenta, one of the world's largest biotechnology companies, had for years been selling transgenic corn not approved for human consumption. About 133 million kilograms of the corn made it into the food chain in the US... that doesn't exactly inspire confidence.
In spite of these sorts of problems, biotechnology is still considered the darling of modern agriculture. That's unfortunate, because we'd be better off looking at our entire food system rather than just a tiny part of it. In the farm-scale studies, for example, transgenic crops were tested against conventional counterparts, using standard commercial agricultural practices. Yet we already know that these standard practices are causing problems due to soil erosion, nitrogen runoff and pesticide use. It would have been even more interesting to compare the transgenic and conventional crops to an organic system, which has proven to produce similar yields, without many of the problems associated with conventional agriculture.
Ultimately, what matters is that we develop a sustainable food system that provides us with healthy food and does not degrade the natural systems that sustain us and other life forms. Genetically modified crops may or may not eventually become part of that system, but right now they are being treated like our best bet. If our goal is to make money in the short term, then maybe that's true. But if our goal is to create a safe, sustainable food system, the evidence just isn't there.
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