Corralling Roundup®

Marc Lappé, Ph.D. (July 24, 1996)

Roundup®, also known by its chemicals name glyphosate, is probably the world's most widely used herbicide if not today, certainly within the next two to three years. The reasons for its popularity are threefold: 1) at first blush, it appears relatively safe for higher organisms; 2) it has a broad range of killing power for both wanted and unwanted vegetation; and, 3) many of the most valuable commercial plants are now being genetically engineered for Roundup® resistance. If Monsanto, Roundup®'s progenitor, has its way, these factors translate into the beginning of a global dependency on this single chemical.

Once a significant portion of the major cash crops in the world are made genetically resistant to Roundup®, it would be foolhardy for any farmer to use any other herbicide on his crops. This is so because with the advent of genetic resistant crops, widespread in-season and out-of-season spraying will be possible to maximize land use that would otherwise be too contaminated to permit crop rotation or the introduction of off-season nitrogen-fixing cover. (Such a development has already transpired with the introduction of the new flax variety known as Triffid in England.)

This state of affairs means that we are on the cusp of something truly revolutionary: A broad cross section of agricultural operations world-wide are about to become dependent on a single chemical. The issue here is that a whole pesticide treatment system is being developed that is based on an uncertain floor of toxicity and ecological data. We are right now a stone's-throw away from boosting this single chemical as the major herbicide for crop production in the developing nations. Once transgenic crops like corn, canola, cotton, and soybeans that have been expensively reprogrammed genetically for resistance to Roundup® are in place, it will prove nearly impossible to reverse this process of herbicide dependency. Unless more caution is used, it is likely that by the time any genuine concerns are raised, we will have created an economic imperative for Roundup® dependency.

Recent public pronouncements from Monsanto, Roundup®'s maker, make it seem as if any environmentalist who expresses concern about residual unknowns concerning its product is all wet. Dan Holman, Communications Manager of Monsanto in St. Louis, recently wrote that critics are unduly spreading alarm about Roundup® and implies that its use in "delicate ecosystems" like the Galapagos Islands proves its environmental safety. According to Holman, Roundup® and its congener products Roundup Pro® and Rodeo® are safe to use "as labeled." Of course, these labels contain strong cautionary language about limiting use and avoiding skin contact. And the use of Roundup® in sensitive ecosystems is so highly circumscribed as to belie their choice as an example of environmental safety.

There is in fact substantial reason for concern about Roundup® from a toxicological viewpoint. While it has been touted as being virtually without toxicity for birds and mammals, people have died from accidental or intentional ingestion, albeit in high dosages. At high doses, glyphosate can also interfere with sperm production in animals. While genetic tests are equivocal, the critical question of whether or not Roundup® can damage the immune system has never been adequately studied.

In all of these tests, Roundup® is tested as the "pure" chemical. According to Monsanto representatives contacted by this Center, the newest version of Roundup® contains the same surfactant as its parent compound, a chemical known a POEA (polyethoxylated tallowamine), along with other "proprietary" chemicals as a blend. POEA is about three times as toxic as glyphosate in standard toxicity assays. These "proprietary" ingredients have never been tested in concert with the parent glyphosate compound in government tests, leaving open how much additional toxicity may be generated by surfactants.

Because Roundup® is highly persistent once on the ground (the time it takes for half the chemical to disappear ranges from 24-249 days), Roundup® will be present long after a single spray operation is completed. Final degradation depends on active soil cultures of microorganisms, some of which are abolished by the chemical in the first place. In relatively high doses, it appears to interfere with the migration of salmon and has high toxicity for fish generally. These features raise issues of concern that transcend standard toxicity tests because they imply that ecological disruption is likely after the sustained application. Over time, reliance on Roundup® will inevitably increase, or at least that is Monsanto's plan.

A whole cascade of problems from such dependency is likely. First, the genetically engineered plants will be expressing a novel proteinaceous enzyme that is needed to break down Roundup®. This protein itself may be allergenic and persists as a novel contaminant in the final product, be it a soybean or potato. Moreover, high level treatment strategies will inevitably leave Roundup® and its "inert" ingredients as residues in the final food product. New taste tests have already shown that animals like gerbils can detect this pesticide contaminant in their feed. Distant impacts of high soil residues, notably in interfering with nitrogen fixation in clover and related species, may ultimately reduce soil fertility, increasing reliance on additional fertilizer use. A chemical no-growth zone for plants other than the targeted commercial species is also potentially disastrous from an ecological viewpoint. Moreover, with residual uncertainty about being able to control the incorporation of the novel resistance gene into unwanted species, the whole edifice of chemical dependency could disintegrate overnight.

Our experience with attempting to chemically rein in natural communities, be it with pesticides or antibiotics, shows us that any massive use and chemical reliance courts an evolutionary nightmare. The consequence of chemical dependency is to reduce species diversity and encourage the resulting destabilization of ecosystems. Eventual resistance in unwanted strains of pests or weeds is a virtual certainty, creating increased need for higher dosages or still other chemical fixes.

We are well on the path to such a scenario. Breeding in genetic resistance to Roundup® virtually assures that farmers will escalate the concentrations of this and related chemicals that they will use. Then, old assumptions about low-dose applications and lack of toxicity will have to be thrown out the window. Further reliance on continued use of Roundup® will put farmers who cannot afford the transgenically altered seed at an economic disadvantage. The genetically engineered crop variety will then become dominant, creating a greater than ever dependency on herbicide usage to maximize yields. And because the economically desirable plant is now herbicide tolerant, still more chemicals can be applied with seeming impunity to increase nitrogen levels and compensate for other field disruptions caused by reliance on chemical weed control. In time, because of the build up of residues in the soil, traditional soil microbes on which continued soil fertility ultimately depend will doom any return to organic or less chemically dependent farming. Indeed, the day of the small farmer is shortened still further by the scale on which this agriculture must be practiced to maximize utility of production.

This gloomy picture is hardly unrealistic: It is likely to be just the scenario contemplated by Monsanto and Roundup®'s developers. The recent move by Monsanto to take over Agracetus from W.R. Grace points clearly in this direction, since Agracetus holds many of the patents and proprietary processes for transgenically engineering plants and Roundup® is Monsanto's greatest single cash commodity. Glyphosate resistance to create "Roundup® Ready" strains of corn, cotton and soybeans is already a reality. Before we commit a whole generation of farmers to this massive genetic/chemical dependency, it might be wise to consider the full panoply of second- order effects we are going to set in motion.