Grist blogger Nathanael Johnson just posted an interesting pair of articles on the repercussions of GM crop use for environmental quality, specifically the use of insecticide-resistant GMOs versus herbicide-resistant GMOs:
- In the insecticide wars, GMOs have so far been a force for good
- Roundup-ready, aim, spray: How GM crops lead to herbicide addiction
This is an important topic, as the potential for reduced chemical use in agriculture is one of the main arguments for GMO crops, now even advanced by some environmentalists who were formerly bitter opponents of GM. As the title suggests, Johnson argues that Bt insecticide-producing GMOs have been net-beneficial, as the specificity of Bt to the most problematic insects has improved the feasibility and economics of integrated pest management, compared to blanket use of the nastiest insecticides that arbitrarily kill beneficial and detrimental insects alike. In contrast, he argues that glyphosate herbicide-resistant crops have been net-detrimental, as they have shifted the economics of production towards ubiquitous use of this single (albeit relatively mild) herbicide. This is not my area of expertise at all, but the idea of technologies that micro-target certain pests encouraging diverse management and those that are non-selective encouraging monolithic management makes intuitive sense.
Related, a new study published in Critical Reviews in Biotechnology compiled almost 1800 academic papers on the topic of GMO effects on biodiversity, gene flow to native species, and implications for human health (the total number of which is increasing by 150-200 papers per year!!):
It’s very interesting reading for out-of discipline folks like myself want to learn more about the large and highly diverse literature underlying this controversial topic. I was not familiar with (and was actually a little overwhelmed by) the large number of different ‘what-if’ hypotheses of potential dangers of GMO, but the outlook of the review is very sanguine, concluding that no significant environmental or human health effects have been documented, though imperfect experimental designs/statical techniques in a small number of studies and a lack of public accessibility of experimental results from industry has probably contributed to the perception of controversy.
As an aside, I get the impression that the debate over GMO safety is not about science at all, but about philosophy and personal outlook on technology. If you’re they type of person who is skeptical about technology, it’s probably easy to imagine that there are all sorts of potential side effects that the scientists don’t yet have the techniques to observe. Of course, “proving” that GMOs are perfectly safe suffers from the problem of induction; all science can do is point to the lack of evidence for the null hypothesis that GMOs are harmful, as this review does.