Wednesday, January 16, 2013

GMO's, Science, and the Burden of Proof


Environmentalist Mark Lynas has created big waves among foodies recently by making an about-face on genetically modified foods (http://www.youtube.com/watch?v=obC2TwtJhuI).

He got to a point where he noted a discrepancy between his activism on climate change, where he was arguing that the broad scientific consensus ought not be ignored, and his activism on GMO food, where he was part of a group that held the broad scientific consensus on the safety of GMO's in deep suspicion. He begin to see the same insularity and circularity in the anti-GMO arguments that he saw among climate change sceptics.

I have not followed the GMO debates closely, but would generally be suspicious of these “Frankenfoods,” a phrase Lynas himself once helped to coin. But I found Lynas' readiness to change his mind based on the evidence admirable. The intellectual rigour that does not allow scientists to pick and choose the results that suit their biases is something we should all aspire to.

Being doctrinaire about GMO food may be precluding some valuable advances. For example, I know that Wes Jackson of the Land Institute has speculated whether GM methods could help in the quest for perennial strains of grain crops. The heavy reliance on annual crops which have to be tilled under every single year has long been a detriment to agricultural soils. Nature keeps the ground covered. Could GM help us do that, and still let us eat grains?

But as little as I know about the GMO science, I feel able to draw some distinctions between climate science and GMO science. I think one can argue that they ask different kinds of questions.

What is the question that climate science has been trying to answer? The questions, as I have understood them, are:
  1. Is the world's climate changing?
  2. Is there a link between human-caused emissions of so-called greenhouse gases and this change?
The evidence, as it has come in from many independent studies across the globe, has been overwhelmingly weighted to answer these two questions in the affirmative.

What is the question the GMO science has been trying to answer? The question has been, are GMO's safe? It strikes me right off the bat that this is a much broader question than the two questions above. Do we mean by this, “Will humans get noticably sick if they eat GMO food?” If so, I can imagine that this question could be answered in the negative, and still leave out many other questions of safety.

The pattern of agricultural research and development has generally been to propose narrow solutions to narrow problems (e.g. profitability, productivity, pest control) and to review the results in a context that excludes broader factors of health: e.g. Soil erosion, nutrient run-off, watershed pollution, biodiversity depletion, rural depopulation, etc.) If the research on GMO's was broad enough in scope to take all such vital factors into consideration, it would be a first in “agri-tech.”

As arduous and massive as the research efforts on climate science have been, it seems to me that the burden of proof for establishing that a human activity is causing harm in the natural world is orders of magnitude smaller than the burden of proof for establishing that a human activity is not causing harm in the natural world. We live in a world that is deeply complex and interconnected. The fact that we lack the scientific methodology to trace how the wingbeat of a butterfly can be the beginning of a hurricane does not make this inherited wisdom saying untrue.

A case in point: Colony collapse disorder - the problem of honey bees disappearing by the millions and never returning to their hives - remains a complex and so far unsolved problem. If unmitigated, it threatens around 40% of the world's food crops, which rely on bee pollination. This dire problem is almost certainly multi-factorial. The broad application of insecticides and the disruptive annual transportation of 3/4 of the US honeybee population in and out of the monocultured almond groves of California are among the suspected stressors, but GMO's have not been ruled out. Studies point to sublethal effects on honeybees from exposure to GMO pollen, affecting feeding and learning behaviours. Not enough to kill a bee perhaps, but quite possibly enough to affect colony viability. It begs the question, what is meant by “safe?”

In this multi-pronged attack from a variety of known, suspected and unknown stressors, how large or small of a factor is GMO in colony collapse disorder? This would be difficult enough to say. To say with any confidence that GMO's are not at all a factor in this problem seems very premature. Science admits we do not fully understand the causes. How then can we already rule out GMO as a suspect?

Then there are other questions, which science does not ask. Questions like: Does GMO food overly concentrate the control of the world's food system in the hands of a few multi-nationals? How is it eroding local self-determination, locally adapted foodways, local culture? Are these losses worth the gains? Are we helping or hurting poor farmers by flooding markets with another cheap food that requires high technology and very few farmers? These are not scientific, but moral questions. No doubt there are sciences that can furnish us with data that could make our moral wrestling well-informed, but the wrestling remains to be done, in the arenas of culture and conscience. The laboratories cannot tell us everything we need to know.

To conclude with Mark Lynas that the debate on GMO foods is “over” seems to me to reduce that debate to the narrowest of questions. While there may be some sense in which GMO's have been scientifically demonstrated to be “safe,” they may yet prove to be harmful to much that is rightly held dear.

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