GMOs: a solution or a problem? A debate between Mark Lynas and Colin Tudge.

• Position: Genetically-modified organisms

Ban, label, or regulate? The dispute over the use of genetically-modified organisms (GMOs) seems endless, but is critical to food security. Although some experts embrace technology, highlighting the benefits of higher yields and nutritional quality of GMOs, others warn that they pose serious environmental and health risks. Environmental writer and GMO supporter Mark Lynas and biologist and GMO critic Colin Tudge shared with the Journal their insights and concerns regarding genetically-modified food.

The Case for GMOs:

Journal of International Affairs: You were a well-known opponent of GMOs, but in a farming conference in Oxford in January 2013, you announced your conversion. Why? How and when did you change your mind?

Mark Lynas: It was a long-term process, which began many years earlier. Between the mid-1990s and 2000, I was an activist against GMOs. That was the period when I was actually involved in destroying GM crops in the fields and spreading campaign information against GMOs. But after that point, I was more focused on being a writer, a science writer, in particular. And my main area of interest was climate change. I wrote two books on climate change, which were very much focused on the science behind the issue. That forced me to become more scientific in my ways of thinking, to look more at the peer-reviewed literature, and to understand scientific methodologies better than I had before when I was an activist. During this time, the fact that there was a strong scientific consensus on climate change was something I would refer to often, and was what kept me clear about what is and is not happening with the world's climate. At this point I realized that there was an equally strong scientific consensus on the safety of GMOs, yet my colleagues and I were making claims against what the scientists

around the world were saying. It was an inconsistent position for me to attack the scientists on one side and to defend the scientists on the other. I wanted to be consistent and to go with the scientific evidence on the two separate issues. In fact, the actual public announcement I made at Oxford was quite later on. I started thinking about this many years before that. I believe I had also written about it in my book "The God Species," which did not gain so much attention because it was not nearly as straightforward and forceful as what I said in my Oxford speech.

Journal: The tipping point came after you were writing an op-ed against GMOs for The Guardian and you realized you didn't believe your own arguments. Can you explain what these arguments were?

Lynas: I had always thought that GMOs increased the use of agrichemicals in farming. But it turns out that there have actually been dramatic reductions in the use of agrichemicals, insecticide in particular. It is less clear with herbicides. But even so, there have probably been benefits in terms of [no-till] farming and carbon retention in the soil. I thought there were potential safety concerns about GMOs. But it turns out that after hundreds of studies and some trillions of meals containing GMO ingredients having been consumed, there has never been a single substantiated health concern. I also thought that GMOs were necessarily advancing the cause of multinational corporations in agriculture, but it turns out that there are public-sector initiatives and open source genetic initiatives going on all the time, in which either GMOs were not patented or open-source patents were available to poorer farmers. I guess I also thought that there was something bad about violating the species barrier and transferring genetic material between unrelated organisms. However, it turns out that viruses do that all the time, and horizontal-gene transfer does happen in nature between unrelated organisms. I do not think I had enough knowledge about biology to even recognize back then that DNA is just a coding system or a different sequence of letters. DNA is the same between all organisms. There is nothing inherently wrong with moving genes around so long as the impacts are well studied and well understood. So when I look at the science of GMOs, I realized I was inconsistent, as was pointed out to me when I wrote this article in The Guardian in 2008. I did not...