by Carey Gillam
Marcela is a registered nurse who works with oncology patients, and she has long feared the adverse effects that pesticide residues could have on her family’s health. She tries to buy organically grown food and feeds her young daughter the healthiest meals she can, so she was shocked and saddened to learn of the weed killer found in her company’s honey. “What can you do? I’m sure you’ll find pesticides in almost everything. It makes you feel so helpless,” she said. “How do we protect our children?”49
Knowing that glyphosate is in honey also upsets Margaret Lombard, chief executive officer of the National Honey Board, which promotes honey products to consumers. She sees the situation as not only an injustice to beekeepers but also an indicator of how hard it is to escape contamination of the larger food supply. “It seems like everything we’re eating has this chemical in it,” she said.50
The FDA’s decision to start testing for glyphosate residues attracted Monsanto’s attention, as would be expected. As testing was ramping up in the spring of 2016, Monsanto’s international regulatory affairs manager, Amelia Jackson-Gheissari, asked Lauren Robin, chief of the FDA’s Plant Products Branch, to set up a time to talk about “enforcement of residue levels in the USA, particularly glyphosate,” according to the FDA records I obtained.51 The FDA said it does not have extended communications with Monsanto on this topic and Monsanto does not influence the FDA’s work. But it’s noteworthy that even as the FDA engaged in conversation with Monsanto about residues, it did not inform the public about the glyphosate residues found in honey or in oats.
It’s clear the government has long been aware of glyphosate residues in food—in one intra-agency e-mail exchange in 2015, FDA chemist Chamkasem said: “I believe we will see a lot of violation for glyphosate.”52 Within a few months after Chamkasem did his tests, the FDA abruptly halted his pesticide residue testing operations, deciding that additional work could and should be handled by other FDA chemists elsewhere. The FDA also suspended glyphosate residue testing for nine months, resuming limited testing in June 2017.
The fact that the FDA and the USDA have dragged their feet on testing for so long frustrates many who are concerned about the pesticide. “There is no sense of urgency around these exposures that we live with day in and day out,”53 said Jay Feldman, executive director of Beyond Pesticides, whose organization met with the EPA in January 2016 to argue for more government action on glyphosate.
The reluctance of the U.S. government to examine food for glyphosate residues has also been noted across the Atlantic, in Europe, where glyphosate is a growing concern. Michael Antoniou, a molecular geneticist in London who has been among many researchers studying glyphosate and formulations such as Roundup, said, “With increasing evidence from laboratory studies showing that glyphosate based herbicides can result in a wide range of chronic illnesses through multiple mechanisms, it has become imperative to ascertain the levels of glyphosate in food and in as large a section of the human population as possible.”54
CHAPTER 5
Under the Microscope
So just how dangerous is glyphosate? Most people would agree that, as with virtually any pesticide, it’s not a good idea to drink it, bathe in it, or inhale it. Farmworkers are trained to wear protective gear when applying or mixing their farm chemicals and to follow an assortment of guidelines to protect themselves and others from harmful exposures. But the question of exactly how dangerous long-term use of glyphosate might be, especially in formulations such as Roundup, has thus far been hard to answer.
Monsanto Company and many leading chemical industry experts tell us that we should trust them and that more research is not needed. The safety of glyphosate and Roundup is proven, they say. But trust is hard to come by when the government does not require robust long-term safety data for a finished product such as Roundup, only for the active ingredient. There have long been concerns that the end product is more dangerous than glyphosate alone, and scientists say it is well-known that extra ingredients in pesticide products not only may themselves be toxic but also may enhance or supplement the toxic effects of the active ingredient. Extra ingredients in pesticides commonly include surfactants that help chemicals stick to the leaves of plants, antifoam compounds, and more. Yet the bulk of industry-sponsored toxicology tests are done using only the active ingredient. As well, there is very little long-term epidemiology data on glyphosate exposure, and there is no established base of information about just how much of the pesticide is in the products we eat and drink because the U.S. Food and Drug Administration (FDA) and the U.S. Department of Agriculture (USDA) have so steadfastly avoided including glyphosate in their testing regimes. And despite industry assurances of safety, there is an international body of published research that contradicts those claims. Several different scientists in several different countries have found associations between glyphosate and disease, most notably a link with non-Hodgkin lymphoma, while independent research on formulated products such as Roundup has found that the combinations of chemicals can be even more hazardous than glyphosate by itself.
In study after study, exposure to glyphosate or Roundup has left laboratory rats and other experimental animals with a range of health problems, including tumors, blood and pancreatic problems, and liver and kidney troubles. Some research showed that exposed male mice developed a sarcoma that started in the lining of their blood vessels, while other work found that glyphosate produced fetal malformations in lab animals. One group of Brazilian scientists found that Roundup appeared to disrupt male reproductive functions by triggering cell death in rat testes.1
A team of British scientists that included Michael Antoniou made headlines in early 2017 with the publication of research linking Roundup to fatty liver disease. The scientists mixed low doses of the weed killer with water and then gave the solution to female rats over a two-year period. The dose was about the same as concentrations found in tap water, according to the scientists, and was actually far lower than the levels found in some foods. At the end of the study period, the researchers examined the organs of the animals and found cell damage and clear evidence of disease.2 Monsanto rejected the findings, as it had with other studies that link glyphosate with disease, saying they were based on flawed data and conducted by agenda-driven scientists. But others saw it as evidence that Roundup was much more harmful than anyone had realized.
Concern grew when a group of Brazilian scientists published research in February 2017 showing that very young lab animals given soy milk laced with glyphosate suffered damaging hormonal changes. The finding raised alarm because mothers often feed soy formulas to their babies as an alternative to breastfeeding, and soy is commonly found to contain glyphosate residues.3
Well before that work, molecular biologist and neuroscientist Andrés Carrasco at the University of Buenos Aires and a group of colleagues set alarm bells ringing across Argentina with a 2010 study that found injections of a very low dose of glyphosate into frog and chicken embryos could cause spinal defects. Carrasco’s work indicated that glyphosate changed levels of retinoic acid, considered fundamental for protecting the body from cancers and for helping embryonic cells develop properly. Those chicken and frog embryos subjected to heavily diluted Roundup showed serious malformations and/or died.4 Carrasco, who was a principal investigator at his university’s Institute of Cellular Biology and Neuroscience when he did the research, was quoted in an Associated Press story in 2013 explaining that his investigation was triggered by reports of increasing birth and spinal defects in farming communities after crops genetically modified to be sprayed directly with glyphosate were approved for use in Argentina. “If it’s possible to reproduce this in a laboratory, surely what is happening in the field is much worse,” Carrasco told the Associated Press. “And if it’s much worse, and we suspect that it is, what we have to do is put this under a magnifying glass.”5 Carrasco died in 2014, but his findings have left lingering questions for health officials in Argentina.
In Sri Lanka, scientific
studies have suggested that a deadly chronic kidney disease that has afflicted thousands of people in farming areas is tied in part to exposure to pesticides, including glyphosate.6 Both Sri Lanka and El Salvador at one time debated a ban on glyphosate because of fears the chemical could be contributing to the epidemic of the new form of chronic kidney disease, which could not be attributed to diabetes, hypertension, or other known triggers. The World Health Organization became so concerned that it funded a study in conjunction with the National Science Foundation of Sri Lanka to delve into the matter. The resulting research report, published in 2013, surmised that a combination of harmful heavy metals and pesticides could be to blame. Glyphosate residues were among the pesticide residues found in the urine of the kidney patients. Also found was cadmium, a highly toxic metal known to cause cancer.7 Cadmium is particularly harmful to humans; it targets the body’s cardiovascular, renal, gastrointestinal, neurological, reproductive, and respiratory systems.
Sri Lankan toxicologist Channa Jayasumana theorized that glyphosate is a key culprit in the kidney disease seen among agricultural workers not just in Sri Lanka but in other countries as well. According to Jayasumana, a member of the Faculty of Medicine and Allied Sciences at Rajarata University of Sri Lanka, glyphosate’s ability to act as a “chelator,” a substance that creates bonds with heavy metals, was causing dangerous compounds that could make their way into food and water and eventually reach a person’s kidneys. Glyphosate was actually patented as a chemical chelator in 1964 by Stauffer Chemical Company, though Monsanto has argued it is not very potent in that role.8 One of Jayasumana’s research papers explained it this way:
Here, we have hypothesized the association of using glyphosate, the most widely used herbicide in the disease endemic area and its unique metal chelating properties. The possible role played by glyphosate-metal complexes in this epidemic has not been given any serious consideration by investigators for the last two decades. Furthermore, it may explain similar kidney disease epidemics observed in Andra Pradesh (India) and Central America. Although glyphosate alone does not cause an epidemic of chronic kidney disease, it seems to have acquired the ability to destroy the renal tissues of thousands of farmers when it forms complexes with a localized geo environmental factor (hardness) and nephrotoxic metals.9
Research also suggests that glyphosate harms human health by exacerbating the damage done by other food-borne chemical residues and environmental toxins. The harm manifests slowly over time, creating conditions that damage cellular systems throughout the body, this theory goes. Some studies have shown that the weed killer is genotoxic, causing DNA damage in human cells that can lead to cancer. Other research indicates glyphosate may harm beneficial gut bacteria needed for healthy immune function.
Many researchers fear that one of the worst impacts of glyphosate on human health may be as an endocrine disruptor, a dreaded term for chemicals that interfere with hormones in the human body in ways that can cause cancerous tumors, birth defects, and other developmental disorders. Endocrine disruptors have been associated with developmental and learning disabilities in children, attention deficit disorder, and cognitive problems.
Humans are very sensitive to very low dosages of endocrine disruptors, according to Andrea Gore, professor and Vacek Chair of Pharmacology at the University of Texas at Austin—especially developing fetuses, infants, and children. “Small fluctuations from the norm can change developmental processes and lead to a dysfunction at the time of exposure, or sometimes, many years after exposure,” Gore said in an interview with Vice magazine for an article about glyphosate.10
Several recent studies have shown the potential adverse health effects of glyphosate as an endocrine disruptor, including the 2017 soy milk study and a 2013 study by a team of four toxicology experts from Thailand who found that glyphosate induced human breast cancer cell growth. “These results indicated that low and environmentally relevant concentrations of glyphosate possessed estrogenic activity,” the scientists concluded.11 A 2009 study by French researchers similarly found that glyphosate-based herbicides triggered endocrine disruption in human cells even at low levels. The scientists warned that the “real cell impact of glyphosate-based herbicides residues in food, feed or in the environment” warranted greater consideration.12 Another study by French researchers, published in 2016, reiterated that warning, finding that glyphosate-based herbicides such as Roundup have endocrine-disrupting effects at concentrations well below those used by farmers.13 Scientists have found indications that Roundup and other glyphosate-based weed-killing products induce cell-cycle dysregulation, a hallmark of cancer, and that Roundup can be toxic to human umbilical, embryonic, and placental cells.14
One study looking at several communities exposed to glyphosate-based formulations found chromosomal damage in blood cells, and scientists said the markers of chromosomal damage were significantly greater after exposure than before exposure in the same individuals.15 In a report issued in October 2016, Pesticide Action Network (PAN) International stated:
Exposure to glyphosate-based herbicides, even at very low doses, may result in reproductive problems including miscarriages, pre-term deliveries, low birth weights, and birth defects. Laboratory studies have shown that very low levels of glyphosate, Roundup … and the metabolite AMPA all kill human umbilical, embryonic, and placental cells. Roundup can kill testicular cells, reduce sperm numbers, increase abnormal sperm, retard skeletal development, and cause deformities in amphibian embryos.16
One study of pregnant women in an Indiana obstetric practice found glyphosate in the urine of over 90 percent of women tested, and it determined that women with higher levels of the pesticide were found to have shorter pregnancies and babies with lower birth weights, outcomes that are believed to translate to long-term health problems.17
Part of the difficulty in establishing clear evidence is the rather obvious fact that researchers cannot ethically use people in experiments with glyphosate, so animal studies and observational studies of the health of people who work in agriculture, spraying crops with Roundup or otherwise being exposed, are the key ways scientists examine the issue. And because the government does not track or collect data on glyphosate residues in food, scientists cannot quantify how that route of exposure corresponds with or affects incidences of disease.
Then there is the problem of trying to identify one pesticide among many that may be the cause of a specific disease. People, particularly farmers, are often exposed to multiple pesticides during their lives, and many pesticides are frequently used together or at least during the same season. Research shows there have been increases in the global incidence of non-Hodgkin lymphoma (NHL) over the past thirty years,18 and even though the rate has leveled off in the United States recently, it is the seventh most common type of cancer in the United States.19 Farmers are at increased risk for the deadly cancer,20 and pesticides are thought to be the chief culprit. But trying to decipher which pesticide or pesticides might be behind the cancer cases has proven challenging.
During the 1980s, the National Cancer Institute conducted three case-control studies of NHL in Nebraska, Kansas, and Minnesota and Iowa—all top U.S. farming states. The Heartland produces millions of bushels of wheat, corn, and soybeans every year, and an array of agro-chemicals are used widely. Glyphosate is a favorite. Researchers later pooled the data to examine how the pesticide exposures affected a farmer’s risk for the blood cancer. Researchers looking at forty-seven different pesticides found that glyphosate and at least eight other “potentially carcinogenic” chemicals used by the farmers showed links to NHL.21
Researchers also found an association between glyphosate and NHL in a separate, much smaller study from 1999.22 And a 2001 study across a large region of Canada found that the more often people used glyphosate, the higher was their risk for NHL.23
There is also fear that glyphosate can be extremely harmful even in low amounts, such as traces of it in our food. By February 2016, around the same time the FDA
was saying it would finally start limited testing for glyphosate residues in food, fourteen scientists from Europe, Canada, and the United States issued what they called a “Statement of Concern … directed to scientists, physicians, and regulatory officials around the world.”24
In the statement, published in an open-access scientific journal, the scientists pointed out that to accommodate the increased use of glyphosate that came with Monsanto’s rollout of its glyphosate-tolerant crops, regulators “dramatically increased” tolerance levels allowed in corn, soybeans, and other crops. Human exposure has been rising, while regulatory estimates about what a “tolerable” daily intake means for people consuming glyphosate residues is based on outdated science, the group said. The scientists said that research shows low levels of these herbicides can do damage to people in the range of what regulators consider safe, and they recommended that regulators reexamine the acceptable daily intake for glyphosate, which is established at 1.75 milligrams (mg) of glyphosate per kilogram (kg) of a person’s body weight per day for Americans but is set much lower in the European Union, at 0.3 mg/kg/day.
The scientists also said that U.S. regulators must prioritize glyphosate for government-led toxicology testing of its common commercial formulations, such as Roundup, because of research showing that when glyphosate is combined with other chemicals, as it is in Roundup and other glyphosate-based herbicides (GBH), the end product may be much more harmful than glyphosate alone. “A fresh and independent examination of GBH toxicity should be undertaken,” and the government should “monitor GBH levels in people and in the food supply, none of which are occurring today,” the scientists concluded.25
One of the commonly used co-formulants of concern in Roundup products has been a chemical called polyethoxylated tallow amine, or POEA, which works to help glyphosate penetrate the surface of plants. POEA is a type of “surfactant,” an ingredient that helps the herbicide adhere to a plant instead of rolling off onto the soil. Monsanto has said POEA poses no danger, but researchers have determined that it actually can be up to 2,000 times more toxic to cells than glyphosate. Fish exposed to POEA in research studies have died, as have rats, even at low levels. Still, regulators have not focused assessments on these types of ingredients or how they interact with glyphosate. Some plaintiffs in the legal cases against Monsanto claim the company knew that robust safety studies were necessary for the combination of glyphosate with POEA in Roundup but skirted research that could have raised alarm bells.
