(Photo courtesy of Vivien Feyer)
Monsanto's herbicide Roundup has been linked to a mysterious
fatal kidney disease epidemic that has appeared in Central America, Sri
Lanka and India.
For years, scientists have been trying to unravel the mystery
a chronic kidney disease epidemic that has hit Central America, India
and Sri Lanka. The disease occurs in poor peasant farmers who do hard
physical work in hot climes. In each instance, the farmers have been
exposed to herbicides and to heavy metals. The disease is known as CKDu,
for Chronic Kidney Disease of unknown etiology. The "u" differentiates
this illness from other chronic kidney diseases where the cause is
known. Very few Western medical practitioners are even aware of CKDu,
despite the terrible toll it has taken on poor farmers from El Salvador
to South Asia.
Dr. Catharina Wesseling, the regional director for the Program on Work and Health (SALTRA) in Central America, which pioneered the initial studies of the region's unsolved outbreak, put
it this way, "Nephrologists and public health professionals from
wealthy countries are mostly either unfamiliar with the problem or
skeptical whether it even exists."
Dr. Wesseling was being diplomatic. At a 2011 health summit in Mexico City, the United States beat back a proposal by Central American nations that would have listed CKDu as a top priority for the Americas.
David McQueen, a US delegate from the Centers for Disease Control and Prevention who has since retired from the agency, explained the US position.
"The idea was to keep the focus on the key big risk factors that we
could control and the major causes of death: heart disease, cancer and
diabetes. And we felt, the position we were taking, that CKD was
The United States was wrong. The delegates from Central America were
correct. CKDu is a new form of illness. This kidney ailment does not
stem from diabetes, hypertension or other diet-related risk factors.
Unlike the kidney disease found in diabetes or hypertension, the kidney
tubules are a major site of injury in CKDu, suggesting a toxic etiology.
Salvadoran farmer returning from the fields, Palo Grande, El Salvador. Photo courtesy of Vivien Feyer.CKDu is now the second leading cause of mortality among men in El Salvador. This small, densely populated Central American country now has the highest overall mortality rate from kidney disease in the world. Neighboring Honduras and Nicaragua also have extremely high rates of kidney disease mortality. In El Salvador and Nicaragua, more men are dying from
CKDu than from HIV/AIDS, diabetes, and leukemia combined. In one patch
of rural Nicaragua, so many men have died that the community is called "The Island of the Widows."
In addition to Central America, India and Sri Lanka have been hit hard by the epidemic. In Sri Lanka, over 20,000 people have died from CKDu in the past two decades. In the Indian state of Andhra Pradesh, more than 1,500 have been treated for the ailment since
2007. Given the rarity of dialysis and kidney transplantation in these
regions, most who suffer from CKDu will die from their kidney disease.
Mural celebrating traditional agrarian life, Juayua, El Salvador. Photo courtesy of Vivien Feyer.
In an investigation worthy
of the great Sherlock Holmes, a scientific sleuth from Sri Lanka, Dr.
Channa Jayasumana, and his two colleagues, Dr. Sarath Gunatilake and Dr.
Priyantha Senanayake, have put forward a unifying hypothesis that could
explain the origin of the disease. They reasoned that the offending
agent had to have been introduced into Sri Lanka within the last 30
years, since the first cases appeared in the mid-1990s. The chemical
also needed to be able to form stable complexes with the metals in hard
water and to act as a shield, protecting those metals from metabolism by
the liver. The compound would also need to act as a carrier and be able
to deliver the metals to the kidney.
We know that political changes in Sri Lanka in the late 1970s led to
the introduction of agrochemicals, especially in rice farming. The
researchers looked for likely suspects. Everything pointed to glyphosate. This herbicide is used in abundance in Sri Lanka. Earlier studies had shown that once glyphosate binds with metals, the glyphosate-metal complex can last for decades in the soil.
Glyphosate was not originally designed for use as an herbicide.
Patented by the Stauffer Chemical Company in 1964, it was introduced as
a chelating agent. It avidly binds to metals. Glyphosate was first used as a descaling agent to clean out mineral deposits from the pipes in boilers and other hot water systems.
It is this chelating property that allows glyphosate to form
complexes with the arsenic, cadmium and other heavy metals found in the
groundwater and soil in Central America, India and Sri Lanka. The
glyphosate-heavy metal complex can enter the human body in a variety of
ways. The complex can be ingested, inhaled or absorbed through the skin.
Glyphosate acts like a Trojan horse, allowing the bound heavy metal to
avoid detection by the liver, since the glyphosate occupies the binding
sites that the liver would normally latch onto. The glyphosate-heavy
metal complex reaches the kidney tubules, where the high acidity allows
the metal to break free of the glyphosate. The cadmium or arsenic then
damages the kidney tubules and other parts of the kidneys, ultimately
resulting in kidney failure and, most often, death.
At this point, this elegant theory advanced by Dr. Jayasumana and colleagues can only be considered hypothesis-generating.
Further scientific studies will need to confirm the hypothesis that
CKDu is indeed due to glyphosate-heavy metal toxicity to the kidney
tubules. For the present, this may be the best explanation for the
Another explanation is that heat stress may be the cause, or a combination of heat stress and chemical toxicity. Monsanto, of course, is standing behind glyphosate and disputing the claim that it plays any role whatsoever in the genesis of CKDu.
While the exact cause of CKDu has not been proven conclusively, both Sri Lanka and El Salvador have invoked the precautionary principle. El Salvador banned glyphosate in September 2013 and is currently looking for safer alternatives. Sri Lanka banned glyphosate in March of this year because of concerns about CKDu.
Mural celebrating traditional agrarian life, Palo Grande, El Salvador. Photo courtesy of Vivien Feyer.
Glyphosate has had an interesting history. After its initial use as a descaling agent by Stauffer Chemical, scientists at Monsanto discovered its herbicidal qualities. Monsanto patented glyphosate
as an herbicide in the 1970s, and has marketed it as "Roundup" since
1974. Monsanto retained exclusive rights until 2000, when the patent
expired. By 2005, Monsanto's glyphosate products were registered in more than 130 countries for use in more than 100 crops. As of 2013, glyphosate was the world's largest selling herbicide.
Glyphosate's popularity has been due, in part, to the perception that it is extremely safe. 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.
Because of glyphosate's reputation for both safety and effectiveness, John Franz, who discovered glyphosate's usefulness as a herbicide, received the National Medal of Technology in
1987. Franz also received the American Chemical Society's Carothers
Award in 1989, and the American Section of the Society of Chemical
Industry's Perkins Medal in 1990. In 2007, he was inducted into the
United States' Inventor's Hall of Fame for his work on the herbicide.
Roundup was named one of the "Top 10 Products That Changed the Face of Agriculture" by the magazine Farm Chemicals in 1994.
Not everyone agrees with this perception of glyphosate's safety. The
first "Roundup resistant" GMO crops, soybeans, were introduced by
Monsanto in 1996. The same year, the first glyphosate resistant weeds began
to emerge. Farmers responded by using increasingly toxic herbicides to
deal with the new super weeds that had developed glyphosate resistance.
In addition to the concern about the emergence of super weeds, a study in
rats demonstrated that low levels of glyphosate induced severe
hormone-dependent mammary, hepatic, and kidney disturbances. Recently
two activist groups, Moms Across America and Thinking Moms Revolution, asked the US Environmental Protection Agency (EPA) to recall Monsanto's
Roundup, citing a host of adverse health impacts in their children from
the herbicide, including failure to thrive, leaky gut syndrome, autism
and food allergies.
Glyphosate is no ordinary herbicide. Besides being the most used
herbicide on earth, it is also the central pillar of Monsanto's temple.
Most of Monsanto's seeds, including
soy, corn, canola, alfalfa, cotton, sugar beets and sorghum, are
glyphosate resistant. As of 2009, Monsanto's Roundup (glyphosate)
products, which include its GMO seeds, represented about half of Monsanto's yearly revenue. This reliance on glyphosate products makes Monsanto extremely vulnerable to research challenging the herbicide's safety.
Glyphosate-resistant seeds are engineered to allow the farmer to
drench his fields in the herbicide to kill off all of the weeds. The
glyphosate resistant crop can then be harvested. But if the combination
of glyphosate and the heavy metals found in the groundwater or the soil
destroys the farmer's kidneys in the process, the whole house of cards
falls apart. This may be what is happening now.
An ugly confrontation has been unfolding in El Salvador. The US government has been pressuring El Salvador to buy GMO seeds from Monsanto rather than indigenous seeds from their own farmers. The US has threatened to
withhold almost $300 million in aid unless El Salvador purchases
Monsanto's GMO seeds. The GMO seeds are more expensive. They are not
adapted to the Salvadoran climate or soil.
The only "advantage" of Monsanto's GMO seeds is their glyphosate
resistance. Now that glyphosate has been shown to be a possible, and
perhaps likely, cause of CKDu, that "advantage" no longer exists.
Mural, Concepcion de Ataco, El Salvador. Photo courtesy of Vivien Feyer.
What is the message from the United States to El Salvador exactly?
Perhaps the kindest explanation is that the United States is unaware
that glyphosate may be the cause of the fatal kidney disease epidemic in
El Salvador and that the government sincerely believes that the GMO
seeds will provide a better yield. If so, a sad mixture of ignorance and
arrogance is at the heart of this foreign policy blunder. A less kind
interpretation would suggest that the government puts Monsanto's profits
above concerns about the economy, environment and health of the
Salvadorans. This view would suggest that a tragic mix of greed and
callous disregard for the Salvadorans is behind US policy.
Unfortunately, there is evidence to support the latter view. The United States seems to be completely behind Monsanto,
regardless of any science questioning the safety of its products.
Cables released by WikiLeaks show that US diplomats around the world are
pushing GMO crops as a strategic government and commercial imperative.
The cables also reveal instructions to punish any foreign countries trying to ban GMO crops.
Whatever the explanation, pressuring El Salvador, or any country, to
buy GMO seeds from Monsanto is a tragic mistake. It is foreign policy
not worthy of America. Let's change it. Let's base our foreign and
domestic policies on human rights, environmental stewardship, health and
Post script: After articles about the seed dispute appeared in the media, The New York Times reported
that the United States has reversed its position and will stop
pressuring El Salvador to buy Monsanto's seeds. Thus far, the aid money
has not been released.