This week, 109 Nobel laureates signed onto a sharply worded letter to Greenpeace urging the environmental group to rethink its longstanding opposition to genetically modified organisms (GMOs). The writers argue that the anti-GMO campaign is scientifically baseless and potentially harmful to poor people in the developing world.

Joel Achenbach broke the news in the Washington Post, and you can read the full letter here. The signatories include past winners of the Nobel Prize in medicine, chemistry, physics, and economics.

Nobel laureates to Greenpeace: Your anti-GMO campaign has to end

The letter notes that scientific assessments have repeatedly found GM foods are just as safe to eat as conventional foods and don’t pose an inherent risk to the environment (though, like any technology, they can be misused). Greenpeace, it argues, is on the wrong side here:

We urge Greenpeace and its supporters to re-examine the experience of farmers and consumers worldwide with crops and foods improved through biotechnology, recognize the findings of authoritative scientific bodies and regulatory agencies, and abandon their campaign against "GMOs" in general and Golden Rice in particular. Scientific and regulatory agencies around the world have repeatedly and consistently found crops and foods improved through biotechnology to be as safe as, if not safer than those derived from any other method of production. There has never been a single confirmed case of a negative health outcome for humans or animals from their consumption. Their environmental impacts have been shown repeatedly to be less damaging to the environment, and a boon to global biodiversity.

The laureates also take Greenpeace to task for seeking to block Golden Rice, a strain of not-yet-approved rice that has been genetically enhanced to produce beta carotene — which, its creators hope, might one day alleviate the Vitamin A deficiency that’s causing widespread death and blindness in the developing world:

Greenpeace has spearheaded opposition to Golden Rice, which has the potential to reduce or eliminate much of the death and disease caused by a vitamin A deficiency (VAD), which has the greatest impact on the poorest people in Africa and Southeast Asia. ... WE CALL UPON GREENPEACE to cease and desist in its campaign against Golden Rice specifically, and crops and foods improved through biotechnology in general;

Now, Greenpeace is far from the only reason Golden Rice has struggled to get regulatory approval — the crop also faces very serious technical challenges. Greenpeace isn’t even the only group seeking to block it. But they’re one of the highest-profile faces of GMO opposition, so the laureates are focusing on them.

In a posted response, Greenpeace denied that they were the main reason Golden Rice has failed to come to market, but still showed no signs of relenting on their broader anti-GMO campaign. We'll get to that, but I do want to elaborate on a few issues the letter raises.

Greenpeace accepts climate science. So why do they dismiss GMO science?

Let’s start off by noting that GMOs will never be a purely scientific issue. Like every policy matter on the planet, the question of how best to incorporate biotechnology into agriculture involves value judgments about what an ideal food system might look like, how to weigh the risks against the benefits, and so on.

But those positions can at least be informed by scientific understanding. To take a different example, on climate change, Greenpeace tends to take very seriously what scientists are telling them. Their website refers frequently to the scientific consensus that the world is getting warmer and humans are the cause.

By contrast, Greenpeace’s public statements on GMOs tend to be startlingly unscientific. On their website, they refer to transgenic crops as "genetic pollution." This is absurd. When scientists create transgenic crops, they frequently use Agrobacterium to transfer genes from one plant or organism to another. But nature does this too: scientists recently found that on two separate occasions in history, Agrobacterium transferred bacterial DNA into the sweet potatoes we eat. Are sweet potatoes also "polluted"? Does anyone believe that?

In fact, many crop scientists tend to see GMOs as sitting along a continuum. Humans have long used all sorts of tools to alter plant DNA and get crops with the traits we desire — this is a big reason farms can feed 7 billion people every year. For thousands of years, farmers interbred crops to alter their genes. Like so:

In the 20th century, plant breeders began exposing crops to radiation or mutagenic chemicals to scramble their DNA and find new traits. Today, scientists use advanced techniques (like transferring genes or CRISPR) that allow even more precision. But it’s the same basic idea. Under the circumstances, it’s no surprise that GMOs don't appear to pose a special health risk. They’re just not fundamentally different.

Now, the vast majority of the public is unaware of this fact. Most people don’t spend much time thinking about how our food is created. (One of the lovely things about the modern age is that we don’t have to.) So, in the abstract, people tend to fall back on their intuitions: Tampering with the DNA of food seems inherently unnatural. Anything "unnatural" triggers disgust. Therefore, GMOs are bad.

Those intuitions are understandable. But they're unsupported by scientific evidence. And rather than seeking to correct those misapprehensions, as they do on climate change, Greenpeace has long sought to inflame those fears. Take this line from their website: "When we force life forms and our world's food supply to conform to human economic models rather than their natural ones, we do so at our own peril." (Never mind that we’ve been doing this since the dawn of civilization.)

The Nobel laureates are, in essence, telling them to knock it off.

Ultimately, the world will face staggering challenges around food and agriculture in the 21st century. The global population is expected to soar past 9 billion, and we’ll need to figure out how to feed everyone without razing too many forests for cropland. Farmers will have to handle the droughts and heat waves that will come with global warming. There are tricky issues around soil health, antibiotic overuse, nitrogen pollution, food distribution, and much, much more.

Genetic engineering certainly won’t solve all those problems. (It might not even solve most of them.) But it is potentially a valuable tool for, say, breeding plants with higher drought tolerance or engineering foods that are more nutritious. See, for example, this important work on vitamin-fortified bananas in Africa. We should be thinking seriously about how to use these tools as a larger strategy for improving our food system — not sowing fears about "genetic pollution."

Greenpeace’s campaign against Golden Rice is incoherent — though the crop faces other serious challenges

The Nobel laureate letter particularly criticizes Greenpeace’s opposition to Golden Rice — rice that’s being modified in an attempt to alleviate Vitamin A deficiency — and here it’s worth expanding a bit.

Last year in Slate, Will Saletan wrote a damning piece on how incoherent Greenpeace’s campaign against Golden Rice was. As research advanced, the group kept shifting its position. A sample:

In 2001, Benedikt Haerlin, Greenpeace’s anti-GMO coordinator, appeared with Potrykus at a press conference in France. Haerlin conceded that Golden Rice served "a good purpose" and posed "a moral challenge to our position." Greenpeace couldn’t dismiss the rice as poison. So it opposed the project on technical grounds: Golden Rice didn’t produce enough beta carotene. … While critics tried to block the project, Potrykus and his colleagues worked to improve the rice. By 2003 they had developed plants with eight times as much beta carotene as the original version. In 2005 they unveiled a line that had 20 times as much beta carotene as the original. GMO critics could no longer dismiss Golden Rice as inadequate. So they reversed course. Now that the rice produced plenty of beta carotene, anti-GMO activists claimed that beta carotene and vitamin A were dangerous. … In the Philippines, where Greenpeace was fighting to block field trials of Golden Rice, its hypocrisy was egregious. "It is irresponsible to impose GE 'Golden' rice on people if it goes against their religious beliefs, cultural heritage and sense of identity, or simply because they do not want it," Greenpeace declared. But just below that pronouncement, Greenpeace recommended "vitamin A supplementation and vitamin fortification of foods as successfully implemented in the Philippines." Under Philippine law, beta carotene and vitamin A had to be added to sugar, flour, and cooking oil prior to distribution. The government administered capsules to preschoolers twice a year, and to some pregnant women for 28 consecutive days. If Greenpeace seriously believed that retinoids caused birth defects and should be a matter of personal choice, it would never have endorsed these programs.

It goes on and on like this. Greenpeace has dismissed scientific reviews showing that Golden Rice does not pose a threat to human health or the environment. Instead, the group continues to file petitions to block all field trials and feeding studies in places like the Philippines.

Now, to repeat what I said above: Greenpeace and other anti-GMO groups aren’t the only obstacle to getting Golden Rice into farmers’ fields. It is fundamentally hard to create a high-yielding strain of rice that consistently produces higher levels of beta carotene. Even after 24 years of testing, researchers still haven’t been able to get Golden Rice to work perfectly in field trials. And they might be struggling even if Greenpeace had given them a pass all along.

In a reply to the Nobel laureates' letter, Greenpeace insisted as much: "Accusations that anyone is blocking genetically engineered ‘Golden’ rice are false," said Wilhelmina Pelegrina, Campaigner at Greenpeace Southeast Asia "‘Golden’ rice has failed as a solution and isn’t currently available for sale, even after more than 20 years of research."

True. But rather irrelevant. It is also fundamentally hard to create a Zika vaccine. It would nonetheless be misguided for me to wage a campaign against researchers working on the project or file a petition to stop trials without any good evidence that it was a risk — even if my protests weren’t the main hold-up.

On a final note, I do think Greenpeace does enormously vital work around the world. They played a crucial role in pressuring soy and beef companies in Brazil to reduce deforestation of the Amazon. Their efforts in China to pare back unnecessary coal-burning plants are one of the most consequential climate campaigns going.

But on GMOs, they are in the wrong. Let's hope this letter prods them to reflect and reconsider.

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