News | December '07 | JUST ANOTHER NON-TARGET SPECIES?
Recent reports of legal threats made by foreign parties against UK campaigners (see SLAPP ON FREE SPEECH – News, November 2007), and of respectable UK scientific journals tricking scientists into print in order to discredited them (see GM SCIENCE AND FREE SPEECH – News, December 2007) will give you some inkling of just how far the biotech industry is prepared to go to stifle opposition to GM food and crops.
Industry research is rarely published, and the extent to which biotech companies bury bad news, or make sure they don't find any unwanted facts in the first place is unknown and largely unknowable. However, the bad news inevitably seeps out through other channels.
GM sceptics, such as the scientists who write for Science in Society have long doubted industry claims of the safety of the Bt-toxins, now widely inserted into biotech crops.
The original, natural, insecticidal Bt-toxin genes are found in a soil bacterium, Bacillus thuringiensis (hence the name 'Bt'). Genetic engineers have synthesised a huge number of Bt-type genes. These are likely to have been altered during the insertion process into the novel organism, and then further individualised by the GM crop as it expresses them. This level of variation may have advantages to the biotech industry: it may be the reason insect resistance to Bt has been surprisingly slow to develop. However, the disadvantages of such uniqueness is that each will present its own unique safety problems, and require unique safety testing. Plus, there's a whole cocktail of them out there in the fields and going into your food chain.
A study by Indiana University has established that Bt toxins in pollen and plant debris are being washed into streams near cornfields. The researchers carried out feeding tests on caddisflies, aquatic insects which are an important food source for fish and amphibia in the stream and normally feed off plant debris. In the laboratory, Bt debris was found to kill and stunt the growth of the caddisflies which ate it. This is not entirely surprising, since caddisflies are related to the pests targetted by Bt toxins.
You might be asking, how did all that Bt toxin manage to get into the environment without anyone noticing its effect on an important non-target insect which would obviously be exposed to it? Easy. The safety tests carried out by the US Environmental Protection Agency were done on Daphnia, a crustacean entirely unrelated to any insect. In other words, one good way to avoid bad news, is to test the wrong thing. Add to this, the extent of testing of Bt-toxins in the form in which they are actually swirling around the environment is rumoured to be close to zero.
Another even less subtle approach to ensuring Bt 'safety' is to avoid the testing altogether, even if it can be done quite simply and there are volunteers ready and willing to do it.
The on-going epidemic of bee die-off which is decimating bee hives in many areas is being blamed by some bee-keepers on Bt crops. One beekeeper, appealed to researchers to carry out a controlled study of matched hives sited in farm and non-farm regions. His idea was rejected out of hand. But undaunted, he is carrying out the experiment himself. Two locations have been carefully chosen, one in rolling farmland and one adjoining a National Forest. New colonies have been established in new hives to avoid disease transfer from previous years. Both sites had ample pasturage of flowers of goldenrod, and the colonies were established after any possible exposure to corn pollen. At the time of writing, the bees in the forest had produced copious honey including nearly 200 pounds extra. The bees near farmland hadn't produced enough honey for their own overwintering needs. The beekeeper is waiting to see if the die-off he experienced last year is repeated.
OUR COMMENT
Since bees are vital pollinators of many wild and food plants, you might think that they would be first in line for health and safety checks before any GM insecticidal crop went into the ground. You might assume that investigation of their catastrophic deaths should be an urgent priority for full investigation. That neither of these has happened may suggest that industry is making sure it doesn't find out what it doesn't want to know, and that scientists' famous curiosity has been dampened down to fulfill industry needs.
The Bt-toxins, even in their natural bacterial forms as used very occasionally by organic farmers, are known to be irritants to humans. The biotech industry claims that its GM maize is designed so that the novel toxins are not expressed in the corn kernels we eat. However, while Nature is very good at designing genes which express themselves in a highly specific way to produce stable substances in specific tissues, man's simplistic efforts to imitate this tend to be unstable and 'leaky'. It would be unrealistic to assume Bt food is toxin-free.
The next generation of Bt crops is emerging with a double Bt whammy: two genes for different Bt toxins to target two different insect pests at the same time. The effect of multiple toxins in the same ecosystem will undoubtedly damage a lot more than two insects.
Like the caddisfly, YOU could become another untested, non-target species, harmed by Bt in your food. Like the bee colonies which keep inexplicably collapsing, scientists will never find the curiosity to do the experiment to find out why. Unless YOU demand it.
SOURCES:
- San Francisco Chronicle 10.11.07
- Indiana University Press Release 8.10.07
- Institute of Science in Society Press Release 30.10.07.