Whose Science Should We Venerate? GMOs, pesticides, environmental concerns, and other animals
Presenter: Barrie Webster
The adventures with GMOs follow those with pesticides and industrial chemicals.
1. Organic chemistry-derived chemical pesticides (DDT and 2,4-D) emerged during World War II were seen as marvels because they killed unwanted organisms – insects (e.g., mosquitoes and codling moth) and plants (e.g., broad-leafed weeds in crops and lawns).
2. Pesticides broke down to form metabolites or degradation products that in some cases were more acutely toxic than the parent pesticides themselves (e.g., organophosphates).
3. Pesticides needed to be screened for their acute toxicity not only to humans and other mammals, but to other possibly beneficial (non-target) organisms. Enter Rachel Carson). Non-target organisms (natural predators and pollinators) were ecologically important enough that a whole new science of environmental toxicology sprang up during the 1970s.
4. During the 1970s and 1980s, chronic toxicity such as carcinogenicity and mutagenicity needed to be tested. This fact had been completely missed by earlier investigators (e.g., dioxins, fire retardants).
5. In the 1990s, Theo Colborn’s work showed the significance of endocrine disruptors – e.g., hormone mimics – in environmental toxicology. Extremely low levels effected developmental changes in embryos, for instance.
6. Along came (in the 1990s) genetically modified organisms as food sources. Equivalency seen as safety.
– many GMO food products shown to be OK (just a very few exceptions) but
– environmental concerns (e.g., GM wheat)
– toxicological concerns (e.g., GM potatoes)
– irreversibility of contamination of natural populations and neighbouring crops (Schmeiser)
At each turn, there have been detractors who tried to suppress the science that showed concerns were warranted and cast doubt on the competence of the scientists involved. There is a cycle of scientific error that seems to repeat itself. Unintended damage often occurs before the dangers are understood.
The scientific advances are impressive, but not necessarily safe enough. That work requires not only scientific expertise, but wisdom – requires scientists unconnected to vested interests.
Humanists need to recognize that the science on which they base their life-stance is not without its flaws. Constant vigilance, questioning, and long term perspectives are required.
Pesticide discussion in latter half: http://www.bmartin.cc/pubs/88psa/88psa_BakerManwell.html