Of Mice, Monsanto and a Mysterious Tumor

(U.S. Right to Know) Call it the case of the mysterious mouse tumor. It’s been 34 years since Monsanto Co. presented U.S. regulators with a seemingly routine study analyzing the effects the company’s best-selling herbicide might have on rodents. Now, that study is once again under the microscope, emerging as a potentially pivotal piece of evidence in litigation brought by hundreds of people who claim Monsanto’s weed killer gave them cancer.

This week tissue slides from long-dead mice in that long-ago research study are being scrutinized by fresh eyes as an expert pathologist employed by lawyers for cancer victims looks for evidence the lawyers hope will help prove a cover-up of the dangers of the weed killer called glyphosate.

Glyphosate, which is the active ingredient in Monsanto’s branded Roundup products, is the most widely used herbicide in the world, and is applied broadly in the production of more than 100 food crops, including wheat, corn and soy, as well as on residential lawns, golf courses and school yards.

Residues have been detected in food and human urine, and many scientists around the world have warned that exposure through diet as well as through application can potentially lead to health problems. The World Health Organization’s International Agency for Research on Cancer (IARC) declared glyphosate a probable human carcinogen in 2015 based on a review of scientific literature, triggering the wave of lawsuits against Monsanto, and pushing California regulators to announce they would add glyphosate to a list of known carcinogens.

What the expert finds, or doesn’t find, is expected to be key evidence in hearings slated for the week of Dec. 11 in dozens of consolidated cases being overseen by a federal judge in San Francisco.

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Rewind to 1983

Monsanto, as well as many other scientists and regulatory bodies, have defended glyphosate’s safety. They say research showing a cancer connection is flawed and hundreds of studies support its safety.

And yet—rewind to July 1983 and a study titled “A Chronic Feeding Study of Glyphosate (Roundup Technical) in Mice.” Following the document trail that surrounds the study offers an illuminating look into how science is not always clear-cut, and the lengths Monsanto has had to go to in order to convince regulators to accept scientific interpretations that support the company’s products.

The two-year study ran from 1980-1982 and involved 400 mice divided into groups of 50 males and 50 females that were administered three different doses of the weed killer or received no glyphosate at all for observation as a control group. The study was conducted for Monsanto to submit to regulators. But unfortunately for Monsanto, some mice exposed to glyphosate developed tumors at statistically significant rates, with no tumors at all in non-dosed mice.

February 1984 memo from Environmental Protection Agency toxicologist William Dykstra stated the findings definitively: “Review of the mouse oncogenicity study indicates that glyphosate is oncogenic, producing renal tubule adenomas, a rare tumor, in a dose-related manner.” Researchers found these increased incidences of the kidney tumors in mice exposed to glyphosate worrisome because while adenomas are generally benign, they have the potential to become malignant, and even in noncancerous stages they have the potential to be harmful to other organs. Monsanto discounted the findings, arguing that the tumors were “unrelated to treatment” and showing false positives, and the company provided additional data to try to convince the EPA to discount the tumors.

But EPA toxicology experts were unconvinced. EPA statistician and toxicology branch member Herbert Lacayo authored a February 1985 memo outlining disagreement with Monsanto’s position. A “prudent person would reject the Monsanto assumption that Glyphosate dosing has no effect on kidney tumor production,” Lacayo wrote. ”Glyphosate is suspect. Monsanto’s argument is unacceptable.”

Eight members of the EPA’s toxicology branch, including Lacayo and Dykstra, were worried enough by the kidney tumors in mice that they signed a consensus review of glyphosate in March 1985 stating they were classifying glyphosate as a Category C oncogen, a substance “possibly carcinogenic to humans.”

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Research rebuttal

That finding did not sit well with Monsanto, and the company worked to reverse the kidney tumor concerns. On April 3, 1985, George Levinskas, Monsanto’s manager for environmental assessment and toxicology, noted in an internal memorandum to another company scientist that the company had arranged for Dr. Marvin Kuschner, a noted pathologist and founding dean of the medical school at the State University of New York at Stony Brook, to review the kidney tissue slides.

Kushner had not yet even accessed the slides but Levinskas implied in his memo that a favorable outcome was assured: “Kuschner will review kidney sections and present his evaluation of them to EPA in an effort to persuade the agency that the observed tumors are not related to glyphosate,” Levinskas wrote. Notably, Levinskas, who died in 2005, was also involved in efforts in the 1970s to downplay damaging findings from a study that found rats exposed to Monsanto’s PCBs developed tumors, documents filed in PCB litigation revealed.

Kuschner’s subsequent re-examination did —as Monsanto stated it would—determine the tumors were not due to glyphosate. Looking over slides of the mouse tissue from the 1983 study, Kuschner identified a small kidney tumor in the control group of the mice – those that had not received glyphosate. No one had noted such a tumor in the original report. The finding was highly significant because it provided a scientific basis for a conclusion that the tumors seen in the mice exposed to glyphosate were not noteworthy after all.

Additionally, Monsanto provided the EPA with an October 1985 report from a “pathology working group” that also rebutted the finding of the connection between glyphosate and the kidney tumors seen in the 1983 study. The pathology working group said “spontaneous chronic renal disease” was “commonly seen in aged mice.” Monsanto provided the report to the EPA stamped as a “trade secret” to be kept from the prying eyes of the public.

The EPA’s own scientists still did not agree, however. An EPA pathologist wrote in a December 1985 memo that additional examination of the tissue slides did not “definitively” reveal a tumor in the control group. Still, the reports by the outside pathologists brought into the debate by Monsanto helped push the EPA to launch a reexamination of the research.

And by February 1986 an EPA scientific advisory panel had dubbed the tumor findings equivocal; saying that given the tumor identified in the control group by some pathologists, the overall incidences of tumors in the animals given glyphosate were not statistically significant enough to warrant the cancer linkage.

The panel did say there may be reason for concern and noted that the tumor incidences seen in the mice given glyphosate were “unusual.”

The advisory panel told the EPA the studies should be repeated in hopes of more definitive findings, and that glyphosate be classified into what the agency at that time called Group D—“not classifiable as to human carcinogenicity.” The EPA asked Monsanto for a repeat of the mouse oncogenicity study but Monsanto refused to do so.

The company argued “there is no relevant scientific or regulatory justification for repeating the glyphosate mouse oncogenicity study.” Instead, the company provided EPA officials with historical control data that it argued supported its attempt to  downplay the tumor incidences seen in the worrisome 1983 study.

The company said the tumors in mice appear “with some regularity” and were probably attributable to “genetic or environmental” factors. “It is the judgement of Monsanto scientists that the weight-of-evidence strongly supports a conclusion that glyphosate is not oncogenic in the mouse.” Monsanto said repeating the mouse study would “require the expenditure of significant resources… and tie-up valuable laboratory space.”

Feds fold

The discussions between Monsanto and the EPA dragged on until the two sides met in November 1988 to discuss the agency’s request for a second mouse study and Monsanto’s reluctance to do so. Members of the EPA’s toxicology branch continued to express doubts about the validity of Monsanto’s data, but by June of 1989, EPA officials conceded, stating that they would drop the requirement for a repeated mouse study.

By the time an EPA review committee met on June 26, 1991, to again discuss and evaluate glyphosate research, the mouse study was so discounted that the group decided that there was a “lack of convincing carcinogenicity evidence” in relevant animal studies. The group concluded that the herbicide should be classified far more lightly than the initial 1985 classification or even the 1986 classification proposed by the advisory panel. This time, the EPA scientists dubbed the herbicide a Group E chemical, a classification that meant “evidence of non-carcinogenicity for humans.” At least two members of the EPA committee refused to sign the report, stating that they did not concur with the findings. In a memo explaining the decision, agency officials offered a caveat. They wrote that the classification “should not be interpreted as a definitive conclusion that the agent will not be a carcinogen under any circumstances.”

Despite the EPA’s ultimate conclusion, the mouse study was among those cited by IARC for classifying glyphosate as a probable human carcinogen. Indeed, many other animal studies have similarly had questionable results, including a 1981 rat study that showed an increase in incidences of tumors in the testes of male rats and possible thyroid carcinomas in female rats exposed to glyphosate and a 1990 studythat showed pancreatic tumors in exposed rats. But none have swayed the EPA from its backing of glyphosate safety.

Christopher Portier, who was an invited specialist to the IARC review of glyphosate and is former director of the National Center for Environmental Health and Agency for Toxic Substances and Disease Registry at the U.S. Centers for Disease Control and Prevention, believes the evaluations applied to glyphosate data by regulators are “scientifically flawed” and putting public health at risk.

“The data in these studies strongly supports the ability of glyphosate to cause cancer in humans and animals; there is no reason to believe that all of these positive studies arose simply by chance,” Portier said.

Monsanto fought the plaintiffs’ request to view the mouse tissue slides, calling it a “fishing expedition,” but was overruled by U.S. District Judge Vince Chhabria who is overseeing the roughly 60 combined lawsuits under his purvey. Monsanto has confirmed that roughly 900 additional plaintiffs have cases pending in other jurisdictions. All make similar claims – that Monsanto manipulated the science, regulators and the public in ways that hid or minimized the danger posed by its herbicide.

“The importance of the original kidney slides and the re-cut kidney slides is immense to the question of general causation and played a critical role in the EPA’s decision to re-categorize glyphosate…” the plaintiffs’ attorneys stated in a court filing.

Plaintiffs’ attorney Aimee Wagstaff reiterated that in a recent court hearing, telling Judge Chhabria that the events surrounding the 1983 mouse study “sort of dominoed,” and potentially are “extremely relevant” to the cancer litigation.

(First published in Environmental Health News)

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USDA Drops Plan to Test for Monsanto Weed Killer in Food

The U.S. Department of Agriculture has quietly dropped a plan to start testing food for residues of glyphosate, the world’s most widely used weed killer and the key ingredient in Monsanto Co.’s branded Roundup herbicides.

(U.S. Right To Know – By Carey Gillam)

The agency spent the last year coordinating with the Environmental Protection Agency (EPA) and the Food and Drug Administration (FDA) in preparation to start testing samples of corn syrup for glyphosate residues on April 1, according to internal agency documents obtained through Freedom of Information Act requests. Documents show that at least since January 2016 into January of this year, the glyphosate testing plan was moving forward. But when asked about the plan this week, a USDA spokesman said no glyphosate residue testing would be done at all by USDA this year.

The USDA’s plan called for the collection and testing of 315 samples of corn syrup from around the United States from April through August, according to the documents. Researchers were also supposed to test for the AMPA metabolite, the documents state. AMPA (aminomethylphosphonic acid) is created as glyphosate breaks down. Measuring residues that include those from AMPA is important because AMPA is not a benign byproduct but carries its own set of safety concerns, scientists believe.

On Jan. 11, USDA’s Diana Haynes wrote to colleagues within USDA: “Based on recent conversations with EPA, we will begin testing corn syrup for glyphosate and its AMPA metabolite April 1, 2017 with collection ending August 31, 2017. This program change will need to be announced at the February PDP Conference Call.” Haynes is director of a USDA Agricultural Marketing Service division that annually conducts the Pesticide Data Program (PDP), which tests thousands of foods for hundreds of different pesticide residues.

The USDA spokesman, who did not want to be named, acknowledged there had been a glyphosate test plan but said that had recently changed: “The final decision for this year’s program plan, as a more efficient use of resources, is to sample and test honey which covers over 100 different pesticides.” Glyphosate residue testing requires a different methodology and will not be part of that screening in honey, he said.

The USDA does not routinely test for glyphosate as it does for other pesticides used in food production. But that stance has made the USDA the subject of criticism as controversy over glyphosate safety has mounted in recent years. The discussions of testing this year come as U.S. and European regulators are wrestling with cancer concerns about the chemical, and as Monsanto, which has made billions of dollars from its glyphosate-based herbicides, is being sued by hundreds of people who claim exposures to Roundup caused them or their loved ones to suffer from non-Hodgkin lymphoma. Internal Monsanto documents obtained by plaintiffs’ attorneys in those cases indicate that Monsanto may have manipulated research regulators relied on to garner favorable safety assessments, and last week, Congressman Ted Lieu called for a probe by the Department of Justice into Monsanto’s actions.

Along with the USDA, the Food and Drug Administration also annually tests thousands of food samples for pesticide residues. Both agencies have done so for decades as a means to ensure that traces of weed killers, insecticides, fungicides and other chemicals used in farming do not persist at unsafe levels in food products commonly eaten by American families. If they find residues above the “maximum residue level” (MRL) allowed for that pesticide and that food, the agencies are supposed to inform the EPA, and actions can be taken against the supplier. The EPA is the regulator charged with establishing MRLs, also called “tolerances,” for different types of pesticides in foods, and the agency coordinates with USDA and FDA on the pesticide testing programs.

But despite the fact that glyphosate use has surged in the last 20 years alongside the marketing of glyphosate-tolerant crops, both USDA and FDA have declined to test for glyphosate residues aside from one time in 2011 when the USDA tested 300 soybean samples for glyphosate and AMPA residues. At that time the agency found 271 samples contained glyphosate, but said the levels were under the MRL – low enough not to be worrisome. The Government Accountability Office took both agencies to task in 2014 for the failure to test regularly for glyphosate.

Europe and Canada are well ahead of the United States when it comes to glyphosate testing in food. In fact, the Canadian Food Inspection Agency (CFIA) is preparing to release its own findings from recent glyphosate testing. The CFIA also routinely skipped glyphosate in annual pesticide residue screening for years. But it began collecting data in 2015, moving to address concerns about the chemical that were highlighted when the World Health Organization’s International Agency for Research on Cancer (IARC) classified glyphosate as a probable human carcinogen in March 2015.

Canadian food activist and researcher Tony Mitra obtained more than 7,000 records from CFIA about its glyphosate testing last year, and claims that results are alarming, showing glyphosate pervasive in many foods. CFIA would not respond to requests for comment about its glyphosate testing.

One of the USDA’s explanation’s for not testing for glyphosate over the years has been cost – the agency has said that it is too expensive and inefficient to look for glyphosate residues in food headed for American dinner tables. And because glyphosate is considered so safe, testing would be a waste of time, the USDA has stated. That argument mimics Monsanto’s own – the company, which patented glyphosate in 1974 and has been a dominant provider of glyphosate ever since, says if the USDA did seek to test for glyphosate residues in food it would be a “misuse of valuable resources.”

FDA TESTS REMAIN IN LIMBO

The FDA began its own limited testing program for glyphosate residues – what it called a “special assignment” – last year. But the effort was fraught with controversy and internal difficulties and the program was suspended last fall. Before the suspension, one agency chemist found alarming levels of glyphosate in many samples of U.S. honey, levels that were technically illegal because there have been no allowable levels established for honey by the EPA. That revelation caused angst in the beekeeping industry and at least one large honey company was sued by consumer organizations over the glyphosate contamination. The same chemist also found glyphosate levels in many samples of oatmeal, including infant oat cereal. The FDA did not publicize those findings, but they were revealed in internal records obtained through a FOIA request.

Officially, the FDA was only looking for glyphosate residues in corn, soy, eggs and milk in last year’s testing assignment, though internal records discussed tests on sugar beets, popcorn, wheat and other foods or grains. Newly obtained FDA documents show the agency is engaged now in a “glyphosate collaboration” designed to validate the testing methodology to be used by multiple FDA laboratories.

“Once the first phase of this collaboration is completed and approved by quality control reviewers, the special assignment can be restarted,” said FDA spokeswoman Megan McSeveney.

CropLife America, an industry organization that represents the interests of Monsanto and other agrichemical companies, keeps a close eye on the government’s pesticide residue testing. Last year the organization sought to diffuse potential legal problems related to glyphosate and other pesticides in honey by asking EPA to set a blanket tolerance that would cover inadvertent contamination of honey by pesticides. Records show regulators have found 26 different pesticides in honey samples in past tests.

CropLife also has complained to USDA that data from its testing program is used by proponents of organic agriculture to promote organics over conventional foods. The group last year sent USDA a series of questions about its testing, and asked USDA: “What can we do to assist you in fighting these scaremongering tactics?”

The USDA’s most recent published report on pesticide residues in food found that for 2015 testing, only 15 percent of the 10,187 samples tested were free from any detectable pesticide residues. That’s a marked difference from 2014, when the USDA found that over 41 percent of samples were “clean” or showed no detectable pesticide residues. But the agency said the important point was that most of the samples, over 99 percent, had residues below the EPA’s established tolerances and are at levels that “do not pose risk to consumers’ health and are safe.”

Many scientists take issue with using MRLs as a standard associated with safety, arguing they are based on pesticide industry data and rely on flawed analyses. Much more research is needed to understand the impact on human health of chronic dietary exposures to pesticides, many say.

(First appeared in The Huffington Post.)

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