OMG, GMOs: Pesticide Expert Charles Benbrook

This is the second in a series of Q & A’s on genetically engineered food, which harm the environment by increasing pesticide use, creating pesticide resistant superweeds and contaminating conventional and organic crops. Earthjustice is challenging the USDA’s decision to allow genetically engineered sugar beets and alfalfa onto the market. To learn more, check out our GMO web feature.

EJ: The biotech industry claims that genetically engineered (GE) foods decrease pesticide use. Is that true?  

CB: The Organic Center has done four reports on this question and has found that crops like corn, cotton and soybeans genetically engineered to be resistant to herbicides have actually increased herbicide use by hundreds of millions of pounds over what herbicide use would have been had these crops not been commercialized. So when the biotech industry says that today’s GE crops have reduced and are reducing pesticide use, they’re factuallywrong.

EJ: Why is herbicide use increasing?  

CB: GE crops were being exposed to only one herbicide, glyphosate, which is the active chemical in Monsanto’s Roundup brand herbicide. Whenever farmers try to control weeds with a single chemical, they create selection pressure on the weed population so that weeds that are highly susceptible to one chemical are completely controlled, but those weeds that are less well-controlled do a little bit better every year. These weeds are actually undermining the effectiveness of the Roundup Ready system as a whole. In the southeast it is a technology in active decline and in a few more years it simply won’t be a commercially viable option.

EJ: Did scientists see this coming?

CB: Absolutely. Years before the first herbicide-tolerant crop was planted, weed scientists, weed ecologists, agronomists, environmental groups and farmers openly warned that this was a technology custom-designed to promote the emergence of resistance.

In the first few years, the Roundup Ready system worked incredibly well. But after a few years, the shifts in weed communities got bad enough that farmers had to apply the herbicide a second or third time. And because some of the weeds weren’t as sensitive to glyphosate, farmers began adding a new family of herbicide chemistry into their program. This is when both the cost of weed control in the Roundup Ready system and the volume of herbicides applied started to quickly rise. That’s been the story for almost a decade now, and it’s been getting progressively worse every year. This is why we see crews of men in the southeast going out into Roundup Ready cotton and soybean fields with hoes to manually remove glyphosate-resistant weeds like Palmer amaranth, which grows so vigorously it can grow stalks as big as a man’s wrist. In some badly infested fields, the stalks of the weeds are so tough that they actually break the cotton harvesting equipment. That doesn’t bode well for the harvest outcome.

EJ: Last year, Monsanto finally admitted that glyphosate-resistant weeds are a problem. What was its solution?

CB: Spray more. Monsanto’s proposed solution is to produce GE crops resistant to multiple herbicides, so that farmers can spray three or four different herbicides at the same time in the hope that at least one will still work. It’s a strategy that’s comparable to pouring gasoline on a fire to put it out.

Now that farmers are forced to turn away from glyphosate, they’re finding that there really aren’t a lot of new herbicides to deal with resistant weeds. That’s why the industry is creating crops tolerant to 2,4-D and Dicamba, herbicides that have been around for 30-plus years and are at the upper end of the risk profile. There are three big risks that are going to go up as 2,4-D and Dicamba are sprayed more widely: birth defects and reproductive problems, damage to non-target vegetation, and impacts on aquatic ecosystems. These are volatile herbicides and they’re extremely toxic, much more so than glyphosate. People who think that we can spray 50 or 100 million pounds of these herbicides a year and not pay a price just aren’t paying attention.

EJ: The biotech industry claims we need these crops to feed a growing population. What’s the alternative?

CB: First of all, the vast majority of GE crops are grown to feed animals in feedlots. The meat, dairy and poultry products are then fed to what is regarded as the economic elite when you look at world population as a whole. The remaining major GE crop is cotton, which people don’t eat. So it is factually inaccurate to say that today’s GE crops are contributing substantially to meeting food needs among the food insecure because the food insecure are not eating Big Macs, pork chops and milk shakes on a daily basis.

The alternative is to back away from herbicide-tolerant crops and provide farmers with greater supplies of seeds that aren’t genetically engineered. Right now, virtually the whole seed supply is genetically engineered so farmers don’t have a choice. If new science showed that herbicide-tolerant crops were the cause of autism, for example, an immediate ban on GE soybeans could not happen because there wouldn’t be enough seed to plant more than 10 percent of the soybean crop.

EJ: Is organic food a viable alternative to GE crops?

CB: There’s enough organic corn, soybeans, tomatoes, grapes, apples and leafy greens being grown to remove any serious doubt about whether it’s possible to grow these crops organically. Clearly it is possible. And it’s also pretty clear that experienced organic farmers, after they’ve gone through the transition and really restored vitality to their soils, are going to harvest more biomass off of their farm than if the farmer managed the operation conventionally. If there were a level playing field across U.S. agriculture, there would be a lot more acres planted to non-GE varieties and grown either organically or using sustainable methods because they make farmers more money. But, right now the infrastructure and the policy framework for agriculture supports high-energy, high-input GE agriculture. Because of those investments and policy bias, energy-intensive, GE-based conventional systems are more profitable. But such systems are not more profitable because they are more efficient or more productive.

Listen to the entire interview.