What would happen if the US or the world banned the use of GMO (genetically modified organism) crops? A new study out of Purdue addresses that question.

The authors estimated the reduction in yields for corn, soybeans, and cotton if GM traits were abandoned. They then plugged the results into a well-established model of how much additional land would be needed to make up for that reduction in yield. They found:

Eliminating all GMOs in the United States, the model shows corn yield declines of 11.2 percent on average. Soybeans lose 5.2 percent of their yields and cotton 18.6 percent. To make up for that loss, about 102,000 hectares of U.S. forest and pasture would have to be converted to cropland and 1.1 million hectares globally for the average case.

The most significant environmental footprint of agriculture is land use. Every hectare (2.471 acres or 10,000 square meters) of forest or pasture that you convert to farmland increases carbon in the atmosphere contributing to global warming. Further, converting land to farmland reduces natural habitat or land for grazing.

For example, environmentalists have warned about declines in the monarch butterfly, implying that GMOs may be to blame (despite the utter lack of evidence for this claim). Declines are due to the loss of milkweed, which the butterflies need to lay their eggs. Loss of milkweed, in turn, is due to land use for farming and the use of herbicides.

Anti-GMO activists have tried to link the use of herbicides to the use of GMOs, but this is not valid. Herbicides are used whether or not the crop is GMO, and no matter what, farmers have to eradicate weeds to optimize their yields. Ultimately the key factor is the amount of land used to grow crops, and therefore displace natural weeds like the milkweed.

The deeper point is that when considering the risks and benefits of any technology, this must be put into the context of the risks and benefits of the alternative. Anti-GMO activists talk exclusively about the hypothetical risks of GMOs, but fail to consider the alternative – the very real risk of not taking advantage of GM technology.

The authors of this recent study are not the first to point out that land use is the biggest factor to consider when determining the environmental impact of agriculture. Displacing an additional 102,000 hectares of land to use for farming is a huge factor that must be considered.

This number – the amount of additional land needed for agriculture if we do not take advantage of GM traits – will only grow larger in the future. As our population grows, we will need to grow more food. Biofuels are another variable, and some argue that we should not depend on biofuels to reduce carbon emissions because of the additional land they require. But, to whatever extent biofuels to figure into our energy future, they will add to the land use differential.

Further, as GM technology improves the benefits of GM traits will only increase. There is currently no GM wheat, for example, but researchers are working on GM wheat varieties that have increased yield, have enhanced photosynthesis, or perhaps even fix their own nitrogen. We should be thinking about how much land we will need for agriculture in 2050 or 2100 with and without GM traits.

Another example of failing to consider the alternative is the focus that many anti-GMO activists have placed on the risks of using glyphosate as an herbicide. Glyphosate, like everything, is toxic at high enough dose. However, the dose that humans would be exposed to through food is far below toxic levels.

As herbicides go, glyphosate is relatively non-toxic. The herbicides it has replaced, in fact, are far more toxic. It is even less toxic than some herbicides allowed in organic farming.

(Glyphosate) has an LD50 of 5600 mg/kg based on oral ingestions in rats, according to EPA assessments, placing it in Toxicity Category III. Rotenone, which is used on some organic farms (though less so in the US in recent years), has an LD50 162-1500 mg/kg, and Copper sulfate, which also sometimes used on certain organic farms, has an LD50 of 30mg/kg.

If you just focus on the possible toxicity of glyphosate you can make is sound scary. When you consider the alternatives, however, it is actually one of the more benign options.

The likely response from some might be not to use any herbicides, but again consider the alternatives, which include tilling or hand weeding. Tilling releases CO2 into the air. Hand weeding is very labor intensive. Both of these methods result in lower yields, which means we are back to increased land use.

When comparing different methods you have to look at the entire picture, from beginning to end, and account for all of the factors involved – not just the one you want to highlight.

Conclusion

The authors of the current study demonstrate one key advantage of using GM traits – increased yield which results in lower land use for agriculture. They also point out that banning GMO will result in higher food prices, of $14-$24 billion per year in the US alone. Higher food prices disproportionately affect those with lower income.

Those who oppose GMOs do not have a solid scientific argument to make. That are essentially ideologues. They are also attempting to “ban” GMOs through the backdoor, primarily through mandatory labeling.

In a recent e-mail to me and others, Mischa Popoff, author of Is It Organic, wrote:

On p. 3 of the bill, SEC. 293. (a) (2) instructs The Secretary of Agriculture (an unelected political appointee) to “establish such requirements and procedures as the Secretary determines necessary to carry out the standard.” As we know from Congressman Mike Pompeo’s original bill, one of these requirements will be a threshold limit on GMO content in non-GMO organic food. And it will be set at the European level of 0.9% in order to bring America into line with Europe and other trading partners. If this passes, it will mean that GMOs will be defined, for the first time ever in America, as contaminants. Henceforth, any organic crop found to have comingling or cross-pollination above that level will no longer be GMO free, and hence will not be able to be certified as organic. Organic farmers will then sue their GMO neighbors for loss of income, something they cannot do at present under the rules of the USDA National Organic Program.

This is another backdoor attempt to “ban” GMOs by making it financially untenable to farm them. Anti-GMO activists make no secret of the fact that their goal is the complete elimination of GM crops. That would be a disaster for the future of agriculture, and would significantly worsen the environmental impact necessary to feed the world.