A summary of scientific evidence showing that genetically modified (GM) soy and the glyphosate herbicide it is engineered to tolerate are unsustainable from the point of view of farming, the environment, rural communities, animal and human health, and economies.
Executive Summary follows; to download the full report, please click here.
Awareness is growing that many modern agricultural practices are unsustainable and that alternative ways of ensuring food security must be found. In recent years, various bodies have entered the sustainability debate by attempting to define the production of genetically modified Roundup Ready® (GM RR) soy as sustainable and responsible.
These include ISAAA, a GM industry-supported group; the research organization, Plant Research International at Wageningen University, the Netherlands, which has issued a paper presenting the arguments for the sustainability of GM RR soy; and the Round Table on Responsible Soy (RTRS), a multi-stakeholder forum with a membership including NGOs such as WWF and Solidaridad and multinational companies such as ADM, Bunge, Cargill, Monsanto, Syngenta, Shell, and BP.
This report assesses the scientific and other documented evidence on GM RR soy and asks whether it can be defined as sustainable and responsible.
GM RR soy is genetically modified to tolerate the herbicide Roundup®, based on the chemical glyphosate. The transgenic modification allows the field to be sprayed with glyphosate, killing all plant life except the crop. GM RR soy was first commercialized in the United States in 1996. Today, GM RR varieties dominate soy production in North America and Argentina and are widely cultivated in Brazil, Paraguay, Uruguay and Bolivia.
Glyphosate is an essential element in the GM RR soy farming system. Because of this, the rapid expansion of GM RR soy production has led to large increases in the use of the herbicide.
The industry claims that glyphosate is safe for people and breaks down rapidly and harmlessly in the environment. But a large and growing body of scientific research challenges these claims, revealing serious health and environmental impacts. The adjuvants (added ingredients) in Roundup increase its toxicity. Harmful effects from glyphosate and Roundup are seen at lower levels than those used in agricultural spraying, corresponding to levels found in the environment.
The widespread spraying of glyphosate on GM RR soy, often carried out from the air, has been linked in reports and scientific research studies to severe health problems in villagers and farmers. A recently published study links glyphosate exposure to birth defects. In some regions around the world, including a GM RR soy-producing region of Argentina, courts have banned or restricted such spraying.
For farmers, GM RR soy has not lived up to industry claims. Studies show that GM RR soy consistently delivers low yields. Glyphosate applications to the crop have been shown in studies to interfere with nutrient uptake, to increase pests and diseases, and to reduce vigour and yield.
The most serious problem for farmers who grow GM RR soy is the explosion of glyphosate-resistant weeds, or “superweeds”. Glyphosate-resistant weeds have forced farmers onto a chemical treadmill of using more and increasingly toxic herbicides. In some cases, no amount of herbicide has allowed farmers to gain control of weeds and farmland has had to be abandoned.
The no-till farming model that is promoted as part of the GM RR soy technology package avoids ploughing with the aim of conserving soil. Seed is planted directly into the soil and weeds are controlled with glyphosate applications rather than mechanical methods.
Claims of environmental benefits from the no-till/GM RR soy model have been found to be misleading. The system has added to the glyphosate-resistant weed problem and has been shown to increase the environmental impact of soy production when the herbicides used to control weeds are taken into account. Also, the production of GM RR soy has been found to require more energy than the production of conventional soy.
There are also serious safety questions over the transgenic modifications introduced into GM RR soy. Contrary to claims by the GM industry and its supporters, the US Food and Drug Administration FDA has never approved any GM food as safe. Instead, it de-regulated GM foods in the early 1990s, ruling that they are “substantially equivalent” to non-GM foods and do not need any special safety testing. The ruling was widely recognized as a political decision with no basis in science. In fact, “substantial equivalence” has never been scientifically or legally defined.
Since then, a number of studies have found health hazards and toxic effects associated with GM RR soy. These include cellular changes in organs, more acute signs of ageing in the liver, enzyme function disturbances, and changes in the reproductive organs. While most of these studies were conducted on experimental animals, the findings suggest that GM RR soy may also impact human health. This possibility has not been properly investigated.
Proponents of GM RR soy often justify its rapid expansion on economic grounds. They argue that the crop increases prosperity for farmers, rural communities, and the economy, so it is irresponsible to ask for proper risk assessment.
However, when on-farm economic impacts of growing GM crops are measured, the results are often disappointing. For example, a study for the European Commission found no economic benefit to US farmers from growing GM RR soy over non-GM soy. The most frequently cited benefit for farmers of growing GM RR soy, simplified weed control, is fast unravelling due to the spread of glyphosate-resistant weeds.
Argentina is widely cited as an example of the success of the GM RR soy farming model. But RR soy production in the country has been linked to serious socioeconomic problems, including displacement of farming populations to cities, concentration of agricultural production into the hands of a small number of operators, loss of food security, poor nutrition, and increased poverty and unemployment.
There are concerns too over the near-monopolistic control of the seed supply in many countries by GM companies. In the United States, this has led to large increases in GM RR soy seed costs – as much as 230 per cent in 2009 over 2000 levels – undermining the economic sustainability of soy farming.
High seed costs, glyphosate-resistant weed problems, and lucrative premiums for non-GM soy harvests are prompting farmers in North and South America to move away from GM RR soy. The industry strategy for countering this trend has been to gain control of the seed supply and restrict the availability of non-GM soy seed to farmers.
GM crops threaten export markets because of consumer rejection in many countries. The discovery of GM contamination of food and feed supplies has repeatedly led to large recalls and major market losses. Ongoing measures to avoid GM contamination are costing the food and agriculture industry millions.
In summary, most of the benefits claimed for GM RR soy are either short-lived (such as simplified and less toxic weed control) or illusory (such as increased yield and less toxic weed control). Many of the claimed benefits of GM RR soy have not been realized, while many of the anticipated problems (such as glyphosate-resistant weeds, disruptions of soil ecology, and negative effects on crops), have been confirmed.
The weight of evidence from scientific studies, documented reports, and on-farm monitoring shows that both GM RR soy and the glyphosate herbicide it is engineered to tolerate are destructive to agricultural systems, farm communities, ecosystems, and animal and human health. The conclusion is that GM RR soy cannot be termed sustainable or responsible.