It’s summer, which means lawn and garden maintenance is in its prime. Some relish in the peacefulness of sitting in the garden as they take in the summer breeze. For others, however, working lawns, landscaping and farming land is much more of a year-round endeavor; it’s their livelihood.

Recently, you may have seen stress-inducing stories related to cases of cancer allegedly associated with exposure to Roundup®, the widely popular glyphosate-based herbicide weed killer, known for its effectiveness at killing weeds while allowing genetically modified crops to flourish. Roundup is used in almost all corn, cotton and soy farming operations (as well as many other agricultural concerns) in the United States, covering more than 168 million acres, and on individual consumers’ personal lawns and gardens.

Given the complexity of Roundup’s alleged connection to cancer, here we take you past the headlines to help you better understand what’s really at play and whether or not you should be concerned.

Some Background
First, the basics: Roundup is a product of Monsanto, which was acquired by Bayer AG in 2018 as part of its crop science division. Today, Bayer is facing 14,000+ lawsuits alleging exposure to Roundup gave frequent users cancer. Additionally, there are more than 30 countries and dozens of U.S. counties and cities with outright bans on Roundup because of its alleged link to the disease.

The main ingredient in Roundup is an organophosphorus (OP) compound called glyphosate. A number of OP compounds are highly effective as insecticides (substances used to kill insects) and herbicides (substances used to kill plants). Some OPs, however, are also toxic to humans. In fact, research published in Interdisciplinary Toxicology in 2016 found that the OP group of pesticides can lead to the irreversible inactivation of acetylcholinesterase, an enzyme essential for nerve function in humans, some animals and insects.

In 1970, Monsanto chemist John E. Franz discovered that glyphosate is an extremely effective herbicide. Four years later, Monsanto released glyphosate to the market for agricultural use under the name Roundup. It quickly grew in popularity and today generates $4 billion in revenue annually, securing its spot as the most popular herbicide in the world. Franz won the National Medal of Technology for his discovery in 1987.

While glyphosate does not discriminate against the plants it kills, many crops are genetically designed to withstand its effects. In the mid-1990s, Monsanto followed its Roundup release with the introduction of patented “Roundup Ready” seeds, which have already been genetically modified to resist the damaging effects of herbicides. The first Roundup Ready crop introduced was genetically modified soybeans, but today the list has grown to include corn, canola, alfalfa, cotton and sorghum.

Cancer Lawsuits Emerge
A risk assessment completed by the World Health Organization’s International Agency for Research on Cancer (IARC) in 2015 largely prompted today’s abundance of pending lawsuits. In that assessment, glyphosate was categorized as a group 2A probable carcinogen. More specifically, the findings pertained to glyphosate’s role in causing a group of blood cancers called non-Hodgkin’s lymphoma (NHL).

IARC experts from 11 countries reviewed the results of more than 1,000 scientific studies on glyphosate, which included experiments on human tissues, cells and lab animals as well as comprehensive analyses of disease patterns in humans. The IARC experts concluded that there was evidence that glyphosate caused cancer in animals and found that some studies indicate glyphosate can trigger chromosomal damage and cancer-causing mutations in human cells.
Monsanto responded quickly to the IARC report, releasing a statement: “Regulatory agencies have reviewed all the key studies examined by IARC—and many more—and arrived at the overwhelming consensus that glyphosate poses no unreasonable risks to humans or the environment when used according to label instructions.”

Despite Monsanto’s statement, the damage to Roundup’s reputation as a safe, trusted weed killer was irreversible, and the IARC ruling ignited lawsuits and policy changes almost instantly. Within six months of the report’s release, 600 scientists from 72 countries signed a manifesto in an attempt to ban the use of glyphosate-based herbicides.

Additionally, several countries considered or enacted a glyphosate ban prior to the IARC report’s release, including Bermuda, Brazil, Colombia, El Salvador, France, Germany, the Netherlands and Sri Lanka. While the United States has not enacted a nationwide Roundup ban, a number of counties and cities in several states have established their own restrictions on its use.

Monsanto, EPA Executives Work Together
The IARC report came one month after the Agency for Toxic Substances and Disease Registry’s (ATSDR) February 2015 announcement of its plan to release a toxicological profile of glyphosate by that October.

After the announcement, U.S. Environmental Protection Agency (EPA) officials began working closely with Monsanto executives to delay the profile, according to text messages, emails and other documents that emerged. Starting in early 2015, Monsanto and EPA officials repeatedly complained to the ATSDR that its toxicological report was “duplicative” of a similar safety review that was being completed by the EPA itself.
Documents, which have been referred to as the “Monsanto Papers,” released in a federal court case suggest that Monsanto and EPA regulators may have intentionally concealed glyphosate’s negative human health risks.

By October 2015, EPA officials successfully got the ATSDR to put its report on hold. The ATSDR refused to kill the review altogether though, saying that “their process is distinguishable and not duplicative.” In response, Monsanto chief scientist William Heydens referred to ATSDR in an email as “VERY conservative and IARC like” and Monsanto regulatory liaison Dan Jenkins expressed concern that the “hazard-based” ATSDR would draw different conclusions than the EPA. In December 2017, the EPA released its human health and ecological risk assessments for glyphosate, which stated that glyphosate is unlikely to be carcinogenic to humans.

After being put on hold a number of times, a 257-page draft of the ATSDR profile was released to the public in April 2019. The toxicological profile supported the March 2015 IARC risk assessment, finding that numerous studies have identified a possible link between glyphosate exposure and NHL.

In response to the profile, the EPA published a second report on April 30, 2019, once again claiming that research “continues to find that there are no risks to public health when glyphosate is used in accordance with its current label and that glyphosate is not a carcinogen.”

Does Further Research Contradict the EPA’s Claims?
An analysis published in the peer-reviewed journal Environmental Sciences Europe in January 2019 suggested that the EPA may have ignored peer-reviewed independent studies in its report, opting instead to rely on research funded by Monsanto to support the company’s position that glyphosate does not cause cancer.

Lead author Charles Benbrook’s, Ph.D., wrote in the analysis that the “IARC’s evaluation relied heavily on studies capable of shedding light onto the distribution of real-world exposures and genotoxicity risk in exposed human populations, while EPA’s evaluations placed little or no weight on such evidence.”

On Feb. 10, 2019, a study published in Mutation Research, a peer-reviewed scientific journal, found that heavy exposure to Monsanto’s Roundup may increase a person’s risk of developing non-Hodgkin’s lymphoma by 41 percent. “This paper makes a stronger case than the previous meta-analyses that there is evidence of an increased risk of NHL due to glyphosate exposure,” said Lianna Sheppard, one of the study’s co-authors and a professor at the University of Washington. “From a population health point of view, there are some real concerns.”

Who May Be At Risk?
There are three paths to glyphosate exposure:
1. Inhalation through the mouth or nose.
2. Absorption through the skin.
3. Ingesting food contaminated with glyphosate. (Note: Current Roundup lawsuits pending are not related to ingestion.)

Individuals who may be at the highest risk of developing NHL from glyphosate exposure are those who use it most frequently, typically as part of their jobs. The frequent and long-term high level of exposure experienced by agricultural workers, groundskeepers, landscapers, gardeners, farmers and pesticide and herbicide applicators may put them most at risk.

The Cancer in Question: Non-Hodgkin’s Lymphoma
Non-Hodgkin’s lymphoma (NHL) is an umbrella term for multiple types of lymphoma that share commonalities with one another. In general, lymphoma is cancer that starts in white blood cells called lymphocytes, which work with other immune cells to fight foreign substances. Lymphoma can originate in the lymph nodes, spleen, bone marrow, thymus, adenoids and tonsils, and can spread to vital organs, such as the brain or liver.

If lymphocytes mutate and become cancerous, their ability to control cell growth and division is disabled. Usually, lymphocytes go through a predictable life cycle: as old lymphocytes die, new ones are created to replace them. In cells infected by NHL, however, the lymphocytes do not die. Instead, they continue to divide, generating an oversupply of lymphocytes in the lymph nodes and causing swelling.

There are two main types of lymphocytes, both of which originate from stem cells in bone marrow. B lymphocytes, or B cells, remain in the bone marrow and make antibodies. T lymphocytes, or T cells, travel to the thymus and help the body kill cancerous and viral cells. Treatment options for NHL include chemotherapy, stem-cell transplants, radiation, and medications. The cell type where NHL originated largely determines the type of treatment patients receive.

Each year, about 75,000 Americans are diagnosed with NHL. According to the American Cancer Society, NHL has an overall five-year survival rate of 71 percent, though this varies widely depending on the presence of risk factors. NHL patients who are over 60 years old, have stage three or four cancer, have NHL in more than one organ outside of the lymph nodes or cannot function without a caretaker have a poor prognosis compared to those without these risk factors.

Non-Hodgkin’s Lymphoma (NHL) Risk Factors:
• Radiation/chemotherapy
• Age: Most cases occur in people in their 60s or older
• Gender: Overall, the risk is higher in men
• Race: Caucasians are more likely to develop NHL than African American or Asian individuals
• Worldwide: Developed areas such as the U.S. and Europe has among the highest rates of NHL
• Family history
• Weakened immune system
• Exposure to certain chemicals and drugs

• Swollen lymph nodes in the neck, armpits, or groin
• Abdominal pain
• Chest pain or trouble breathing
• Chronic fatigue
• Sudden, unexplained weight loss
• Fever
• Night sweats

So is Roundup Safe to Use?
The alleged links to cancer are concerning. However, as of June 2019, the product is still on the market. It’s important to note that the herbicide is, in fact, a toxin, so caution should always be taken when using Roundup. If you are going to use it, please be sure to read the label, wear gloves and follow the instructions accordingly.

• Dewayne Johnson v. Monsanto Co.: In August 2018, a California state jury unanimously ordered Monsanto to pay $289 million to Dewayne “Lee” Johnson, who developed NHL after regularly using Roundup as part of his job as a school groundskeeper. The jury found that Monsanto failed to warn of the carcinogenic dangers associated with Roundup. On Oct. 22, 2018, a federal judge slashed his damages to $78 million—$39 million in compensatory and $39 million in punitive damages. Now, Monsanto has filed an appeal trying to reverse the verdict, claiming that it is legally flawed, there were judicial errors and the plaintiff failed to prove general causation.
• Edwin Hardeman v. Monsanto Co.: In March 2019, a jury in the first federal Roundup case ordered Monsanto to pay $80 million to 70-year-old Edwin Hardeman. Hardeman was diagnosed with NHL in 2015 after using Roundup on his 56-acre property for 26 years. The jury concluded that Roundup was a substantial factor in his cancer diagnosis and said that Monsanto should be held liable for failing to include a warning label on its product. The company plans to appeal the verdict.
• Pilliod v. Monsanto Co.: The plaintiffs are a married couple in their 70s, Alva and Alberta Pilliod. Both were diagnosed with NHL after using Roundup from the mid-1970s until recently on multiple properties they own. On May 13, 2019, a California state court jury ordered Monsanto to pay more than $2 billion in damages. Bayer is expected to appeal.

Glyphosate Safety Reviews and Research: A Timeline

February 2015
The Agency for Toxic Substances and Disease Registry (ATSDR) announces plans to release a toxicological profile of glyphosate by Oct. 2015.
March 2015
The International Agency for Research on Cancer (IARC) classifies glyphosate as a group 2A possible carcinogen.
March – October 2015
EPA officials and Monsanto executives allegedly work together to kill the ATSDR project with repetitive claims that it is “duplicative” of an in-progress review being done by the EPA.
October 2015
Efforts made by Monsanto executives and Environmental Protection Agency (EPA) officials secure a delay of ATSDR’s planned safety review until after the EPA releases its own review.
December 2017
The EPA releases a human health and ecological risk assessment for glyphosate, stating that glyphosate is unlikely carcinogenic to humans.
August 2018
The Environmental Working Group claims that 75 percent of 45 oat-derived products contain levels of glyphosate above what is classified as safe for children’s consumption.
January 2019
An analysis published in Environmental Sciences Europe claims that the EPA ignored peer-reviewed independent studies claiming instead that the agency relied heavily on research funded by Monsanto to support the company’s position that glyphosate does not cause cancer.
February 2019
Former EPA advisors publish research that claims prolonged exposure to Roundup may increase a person’s risk of developing non-Hodgkin’s lymphoma by 41 percent.
April 6, 2019
The ATSDR releases a toxicological profile that supports the assessment completed by the IARC in 2015, which associates glyphosate with cancer.
April 30, 2019
The EPA releases a second report stating that research “continues to find that there are no risks to public health” and glyphosate is not a carcinogen.