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Monsanto’s herbicide Roundup, with glyphosate as the primary ingredient, has recently been linked to a fatal kidney disease epidemic ravaging parts of Central America, India and Sri Lanka. A leading theory hypothesizes that complexes of glyphosate and heavy metals poison the kidney tubules. El Salvador and Sri Lanka have adopted the precautionary principle and taken action to ban the herbicide. In the United States, glyphosate is coming up for review by the Environmental Protection Agency (EPA) in late 2014. Monsanto claims a low risk to human health, but the research is showing something very different. Will these health concerns be enough for the EPA to put restrictions on the herbicide – or to ban it altogether?

Monsanto’s Claims of Safety

Thus far, Monsanto has been successful in portraying Roundup as a safe and effective herbicide. The Monsanto website claims:

Glyphosate binds tightly to most types of soil so it is not available for uptake by roots of nearby plants. It works by disrupting a plant enzyme involved in the production of amino acids that are essential to plant growth. The enzyme, EPSP synthase, is not present in humans or animals, contributing to the low risk to human health from the use of glyphosate according to label directions.

Public Kept in the Dark

Contrary to the company’s claims of safety, a virtual avalanche of scientific studies on animals, including some funded by Monsanto itself, show alarming incidences of fetal deaths and birth defects. The record also shows that Monsanto has known since the 1980s that glyphosate in high doses causes malformations in experimental animals. Since 1993, the company has been aware that even middle and low doses can cause these malformations. These malformations include absent kidneys and lungs, enlarged hearts, extra ribs, and missing and abnormally formed bones of the limbs, ribs, sternum, spine and skull.

These startling revelations can be found in the report Roundup and Birth Defects: Is the Public Being Kept in the Dark? The document is authored by eight experts from the fields of molecular genetics, agro-ecology, toxico-pathology, scientific ethics, ecological agriculture, plant genetics, public health and cell biology. This report, written primarily for a European readership, is highly critical of the biotech industry and of the European Union’s failure to evaluate glyphosate based on the science rather than on political concerns. It calls for an immediate withdrawal of Roundup and glyphosate from the European Union until a thorough scientific evaluation is done on the herbicide. From the report:

The public has been kept in the dark by industry and regulators about the ability of glyphosate and Roundup to cause malformations. In addition, the work of independent scientists who have drawn attention to the herbicide’s teratogenic effects has been ignored, denigrated or dismissed. These actions on the part of industry and regulators have endangered public health. (Authors note: A teratogen is any agent that can disturb the development of an embryo or a fetus. The term stems from the Greek teras, meaning monster).

Monsanto’s Safety Claim Misleads

How is it possible that there are so many adverse health impacts in the test animals, if, as Monsanto claims, “the enzyme, EPSP synthase, is not present in humans or animals”?

The reason is simple. Roundup attacks other enzyme systems, which are indeed present in the animal kingdom.

We owe this knowledge to a group of scientists from Argentina who became concerned about human birth defects in areas of their country where Roundup was being sprayed from airplanes as part of genetically modified (GM) soy production. They decided to do laboratory research to explore whether Roundup would produce similar developmental abnormalities in test animals. Experimenting with frog and chicken embryos, they found that those embryos exposed to the herbicide developed significant malformations, including neural defects and craniofacial malformations similar to the birth defects seen in humans.

Not only did this group of scientists demonstrate that Roundup causes birth defects in the animals tested, but they also were able to demonstrate how Roundup caused the fetal abnormalities. The herbicide increased the activity of the Vitamin A (retinoic acid) “signaling pathway.” It’s called a signaling pathway because it turns genes on and off. Roundup causes an abnormal increase in activity of this pathway, which turns off certain genes. Unfortunately, those very genes are needed for normal embryological development. When the Roundup turns off those genes, birth defects result.

This signaling pathway is shared by virtually all vertebrates, including amphibians, birds and mammals. Thus, it seems quite likely that the birth defects seen in frogs, chickens, rats, rabbits and humans all occur because Roundup attacks this pathway. It also seems likely that if we continue to allow glyphosate to accumulate in the environment, we can expect vertebrates of many types to suffer increasing rates of birth defects. This, of course, includes humans.

Roundup and Birth Defects: the Story From Latin America

The Argentinian researchers were motivated by humanitarian concerns. They were aware of the many worrisome reports of increases in birth defects in Argentina and in other parts of Latin America attributed to aerial glyphosate spraying.

A frightening example is a study of birth defects in Argentina, which found that Cordoba, an area of intensive planting of GM soy and heavy glyphosate use, had a higher incidence of spina bifida (spinal cord protrusion in the lower back), microtia (abnormal ear), cleft lip and palate, polycystic kidney, postaxial polydactyly (extra fingers or toes) and Down’s Syndrome than other regions. Many of these defects are of the type associated with disturbances in the Vitamin A signaling system.

Chaco, Argentina is also a region of intensive GM soy production and heavy glyphosate use. In the last decade, coincident with expansion of GM soy production, birth defects have increased threefold and cancer rates have increased fourfold. A court in the adjacent province of Santa Fe, a major GM soy-producing region, banned the spraying of glyphosate and other agrochemicals in populated areas because of concerns about “severe damage to the environment and to the health and quality of life of the residents.”

Itapua, Paraguay is another GM soy dominated area. Here, residents have suffered a similar fate. Women exposed to glyphosate during pregnancy have a high incidence of fetal deformities similar to those seen in Argentina. These deformities, once again, can be explained by glyphosate’s ability to interfere with the Vitamin A signaling pathway.

Rounding Up the Science

Glyphosate has been conclusively proven to cause birth defects in frogs, chickens, rats, rabbits, and also in humans. Monsanto’s claim that Roundup is safe because it kills weeds by attacking one specific enzyme system not found in animals is misleading. Monsanto has a very large investment in maintaining this illusion. Half of Monsanto’s revenue comes from the sale of Roundup and Roundup Ready seeds.

Roundup attacks vital enzyme systems found in animals, including in humans. It is now clear that interference by Roundup with one of these enzyme systems, the Vitamin A signaling system, can result in severe birth defects. This system is shared by most vertebrates, making Roundup capable of inducing devastating birth defects in a wide variety of amphibians, birds and mammals, and possibly reptiles and fish as well. Allowing glyphosate to continue to build up in the environment will likely cause increased rates of birth defects in all vertebrates exposed, including humans. Exposure, of course, includes the digestion of exposed plants and animals.

Policy Recommendation

The science is clear. There is only one rational response. No family should have to tolerate the risk of significant birth defects – in the United States, or in any part of the world. Roundup and other glyphosate formulations should be banned. Thus far, the voices of public health advocates in this country have been drowned out by those promoting biotechnology and its profits, regardless of the health consequences. We can’t let this continue. Our health, the health of our children and the health of our environment must come first. It is the responsibility of our governmental institutions to protect humanity, not corporate profit.

It’s long past time for us to heed Rachel Carson’s warning from Silent Spring:

If we are going to live so intimately with these chemicals – eating and drinking them, taking them into the very marrow of our bones – we had better know something about their nature and their power.

Pass this on. Raise your voice.