Answers to Common Questions About Glyphosate
Glyphosate has been at the center of recent discussions regarding health, safety and the environment. Included below are quick answers to some frequently asked questions. Each answer contains a link to further information where you can learn more.
Glyphosate is one of the most studied herbicides in the world – and, like all crop protection products, it is subject to rigorous testing and oversight by regulatory authorities. There is an extensive body of research on glyphosate and glyphosate-based herbicides, including more than 800 scientific studies submitted to U.S. or other worldwide regulators in connection with the registration process, that confirm that glyphosate and our glyphosate-based formulated products can be used safely and do not cause cancer. The EFSA, the U.S. EPA and other regulatory authorities around the world have comprehensively and routinely reviewed glyphosate and glyphosate-based herbicides for more than 40 years and their conclusions consistently support the safety of glyphosate and glyphosate-based herbicides when used as directed.
Learn more about the safety of glyphosate in the Glyphosate’s Impact on Human Health and Safety section of our website.
Regulatory authorities, such as the European Food Safety Authority (EFSA) and the U.S. Environmental Protection Agency (EPA) conduct comprehensive evaluations to ensure herbicides, such as glyphosate, pose no unreasonable risk to the environment.
In fact, glyphosate is actually an important tool for helping farmers preserve the environment and biodiversity.
Without glyphosate, farmers would need to rely on plowing (or what is known as tillage), a weed control technique that turns over the soil. Tillage typically requires the use of heavy farm machinery which increases fuel consumption and causes soil disruption, both of which release greenhouse gases, like CO2, that contribute to climate change. Disrupting the soil can also cause erosion, allowing vital nutrients to be washed away with the soil. Glyphosate-based herbicides help enable farmers to control weeds with little or no tillage, which dramatically reduces the carbon footprint and helps farmers maintain healthier soil.
Reducing tillage can diminish soil erosion by up to 90 percent and, in 2014 alone, reduced carbon emissions by an amount equivalent to removing nearly 2 million cars from the road.1,2
In addition, fewer weeds mean crops have less competition – so farmers can produce their harvests with fewer natural resources. Protecting crops from weeds helps to preserve land so it can be used for forage and a natural habitat for wildlife.
Regulatory authorities, such as the European Food Safety Authority (EFSA) and the U.S. Environmental Protection Agency (EPA) conduct comprehensive evaluations and have found that glyphosate, when used as directed, does not cause unreasonable adverse effects on the environment. As part of this process, regulatory authorities specifically evaluate the potential for effects on non-target organisms, including honey bees, and only products that pose no unreasonable risk are approved.
Glyphosate products have been extensively tested in the laboratory and in the field to evaluate potential toxicity to honey bees. This extensive testing has found that glyphosate products pose no acute or chronic adverse effects to honey bees.3,4,5 For example, a comprehensive study by Thompson et al (2014) found no adverse effects on adult bee survival or bee brood survival or development in honeybee colonies treated with glyphosate at levels that exceed environmentally realistic exposures.
No large-scale study has found any link between glyphosate, colony collapse disorder or other causes of hive losses.
Pollinators like honey bees are crucial to helping farmers produce abundant crops. That’s why Bayer has worked for 30 years to understand the challenges affecting bee health and to promote solutions for farmers and beekeepers to help pollinators thrive. The good news is that global honey bee populations have actually increased by 65 percent since the early 1960s.6
Declines in monarch butterflies have been associated with a number of factors including logging of overwintering sites in Mexico, weather events (e.g., freezing temperatures and drought), predation, pathogens and parasites, reduced availability of host plants and nectar sources (like milkweed species) across their migration range and climate change.7
Farmers need to control thousands of weeds species – including milkweed – that compete with crops for water, soil and nutrients. Improved tools, like glyphosate, help farmers grow crops more sustainably and, by extension, often contribute to a decline in the availability of milkweeds on agricultural land for sustaining the monarch population. Effective weed management, however, doesn’t prevent agriculture from being part of the solution and contributing to conservation efforts aimed at establishing habitat for monarchs to thrive. That’s why we are committed to collaborating and working with the monarch conservation community, farmers, agriculture companies, researchers, educators, government agencies, cities, youth and others to improve and protect monarch habitat across the United States.
When it comes to pesticide residues, regulatory authorities have strict rules. In fact, the EPA and the EFSA set daily exposure limits at least 100 times below levels shown to have no negative effect in safety studies.7,8 In the U.S., the Food and Drug Administration (FDA) monitors food to ensure levels stay below the EPA’s limits.
The levels sometimes found in food are incredibly small and nowhere near any level of concern. On Sept. 13, 2019, the U.S. FDA published the results of its annual Pesticide Residue Monitoring Program. The FDA found that all detectable glyphosate residue levels “were below tolerance levels set by the EPA.” Regarding data for pesticides as a whole, the FDA stated that “The findings in this report demonstrate that generally levels of pesticide chemical residues measured by the FDA are below EPA’s tolerances, and therefore at levels that are not concerning for public health.” The FDA’s results are consistent with the findings of other regulatory authorities around the world.
Again, the Environmental Working Group (EWG) is spreading misleading information about glyphosate (Oct. 24, 2018)
A special interest group called the Environmental Working Group (EWG) is again publicizing misleading information about pesticide residues in food. The EWG is perhaps best known for their annual “Dirty Dozen” list, which has been widely criticized and debunked (see this report by Huffington Post and this perspective by UC Davis researcher Carl Winter).
The reality is that regulatory authorities have strict rules when it comes to pesticide residues. The U.S. Environmental Protection Agency (EPA) sets daily exposure limits at least 100 times below levels shown to have no negative effect in safety studies. The levels sometimes found in food are not even remotely close to any level of concern. Indeed, on Oct. 2, 2018, the Food and Drug Administration (FDA) published results of its annual residue testing program and concluded “levels of pesticide residues in the U.S. food supply are well below established safety standards.” The FDA was clear that the glyphosate levels “were below the tolerance levels set by the U.S. Environmental Protection Agency (EPA).”
Nothing in the EWG’s new data demonstrate any safety concern associated with the tested products. All levels reported by the EWG are far below the limits EPA established to protect human health. Even at the highest level reported by the EWG (2,837 ppb), an adult would have to eat 81.5 pounds of the oat breakfast cereal every day for the rest of their life to reach the strict limits set by the EPA. The EWG promoted similar findings in Aug. 15 and was widely criticized for misleading the public (see this article from NBC News and this article by Slate).
Glyphosate has a more than 40-year history of safe and effective use. There is an extensive body of research on glyphosate and glyphosate-based herbicides, including more than 800 rigorous registration studies required by EPA, European and other regulators, that confirms that they are safe for use. Notably, the largest and most recent epidemiologic study – the 2018 independent National Cancer Institute long-term study that followed over 50,000 pesticide applicators and was published after the IARC monograph – found no association between glyphosate-based herbicides and cancer. Additionally, EPA’s 2017 post-IARC cancer risk assessment examined more than 100 studies the agency considered relevant and concluded that glyphosate is ‘not likely to be carcinogenic to humans,’ its most favorable rating.
Statement in response to paper on organic foods in JAMA Internal Medicine (Oct. 23, 2018)
At face value, this paper shows what medical and nutritional science has already confirmed: A diet rich in fruits and vegetables, whether conventional or organic, combined with a healthy lifestyle, leads to better health outcomes. These facts are well established1.
A previous study looking at dietary exposure to pesticides from commodities concluded “exposures to the most commonly detected pesticides … pose negligible risks to consumers, (and) substitution of organic forms … for conventional forms does not result in any appreciable reduction of consumer risks”2.
Pesticides are commonly used in both conventional and organic agriculture. Regardless of whether food is conventional or organic, the U.S. Environmental Protection Agency (EPA) and other regulatory authorities have strict rules when it comes to pesticide residues. These rules ensure that pesticides are used in accordance with best practices and help ensure that the food we purchase for our families is safe to eat. Data from regulatory agencies in Europe, Canada and the United States show that trace residues of pesticides in food, when detectable, are usually far below any level of concern.
As the authors themselves explain, their paper has numerous limitations, including that “our analyses were based on volunteers who were likely particularly health-conscious individuals, thus limiting the generalizability of our findings” and that the cohort participants “exhibit healthier behaviors compared with the French general population.” Additionally, the paper made no actual measurement of pesticide residues or exposure, noting that “strictly quantitative consumption data were not available.”
What is most important for everyone is to eat a balanced diet that is rich in fruits and vegetables, get regular exercise, and avoid smoking and other known cancer risk factors.
World Cancer Research Fund/American Institute for Cancer Research. Diet, Nutrition, Physical Activity and Cancer: a Global Perspective. Continuous Update and Project Expert Report 2018. https://www.wcrf.org/dietandcancer
Winter CK, Katz JM. Dietary exposure to pesticide residues from commodities alleged to contain the highest contamination levels. J Toxicol. 2011;2011:589674. Winter and Katz, 2011
California Glyphosate Case – Dewayne Johnson (Oct. 22, 2018)
The following is Bayer’s statement regarding a decision by Judge Suzanne R. Bolanos on post-trial motions filed by Monsanto in Dewayne Johnson v. Monsanto, a case pending in the Superior Court of the State of California County of San Francisco. Judge Bolanos previously oversaw the Johnson trial.
“The Court’s decision to reduce the punitive damage award by more than $200 million is a step in the right direction, but we continue to believe that the liability verdict and damage awards are not supported by the evidence at trial or the law and plan to file an appeal with the California Court of Appeal.”
“Glyphosate-based herbicides have been used safely and successfully for over four decades worldwide and are a valuable tool to help farmers deliver crops to markets and practice sustainable farming by reducing soil tillage, soil erosion and carbon emissions. There is an extensive body of research on glyphosate and glyphosate-based herbicides, including more than 800 rigorous registration studies required by EPA, European and other regulators, that confirms that these products are safe when used as directed. Notably, the largest and most recent epidemiologic study – the 2018 independent National Cancer Institute long-term study that followed over 50,000 pesticide applicators and was published after the IARC monograph – found no association between glyphosate-based herbicides and cancer. Additionally, EPA’s 2017 post-IARC cancer risk assessment examined more than 100 studies the agency considered relevant and concluded that glyphosate is ‘not likely to be carcinogenic to humans,’ its most favorable rating.”
California Glyphosate Case – Dewayne Johnson (Aug. 10, 2018)
We have deep sympathy for Mr. Johnson’s plight. Our hearts go out to the Johnson family, and we understand their desire for answers. Glyphosate is not the answer. Glyphosate does not cause cancer. The verdict was wrong. We will appeal the jury’s opinion and continue to vigorously defend glyphosate, which is an essential tool for farmers and others. We are confident science will prevail upon appeal. Consumers, growers, and customers can remain confident in the continued safe use of glyphosate. This decision in no way changes our existing registrations for our glyphosate-based herbicides.
California Prop 65 (Aug 16, 2018)
Monsanto is party to two separate legal challenges related to the unjustified listing of glyphosate under Prop 65. These legal challenges are ongoing and happening in parallel:
In November 2017, Monsanto joined a broad coalition of agriculture groups from across the country to challenge the constitutionality of California’s unjustified listing of glyphosate under Prop 65. In December 2017, the Coalition petitioned the U.S. District Court for the Eastern District of California to impose a preliminary injunction to suspend the effect of the listing until the case is decided on its merits. In February 2018, the Court ruled in the Coalition’s favor, granting a preliminary injunction that blocks the implementation of Prop 65’s warning requirements until the Court has the chance to rule on the lawsuit. This preliminary injunction remains in place.
Separately, in January 2016, Monsanto filed a legal challenge in California state court to keep glyphosate off the Prop 65 list. In March 2017 a state judge issued a ruling dismissing our challenge. We subsequently filed a petition for review seeking to have the California Supreme Court consider our appeal of the state judges ruling. On Aug. 16, the California Supreme Court denied our petition. Below is our statement on this latest development.
Statement Issued Aug. 16, 2018: “There is no scientific basis to list glyphosate under Prop 65. The listing contradicts 40 years of science and the conclusions of regulatory bodies around the world. The listing requires judicial intervention and correction. We’re considering our options for further legal action. Meanwhile, the federal injunction in place ensures that unconstitutional warning labels are not required on glyphosate products.”
Brazil Court Lifts Injunction (Sept. 3, 2018)
Bayer welcomes the ruling issued on Sept. 3, 2018 by a Brazilian court that ensures growers in that country will have continued access to glyphosate-based herbicides. Previously, on Aug. 3, 2018, a Brazilian judge issued an injunction that could have prohibited the registration and use of glyphosate-based herbicides and several other crop protection products in the country. The injunction was not a ruling on glyphosate safety but only related to delays in routine regulatory reviews of crop protection products. Subsequently, on Sept. 3, a Brazilian court ruled in favor of a remedy filed by the Federal Government to overturn the injunction before it took effect and ensure that Brazilian growers can continue to use glyphosate-based products. Click here for our statement.
1 https://www.ars.usda.gov/ARSUserFiles/20902500/DavidHuggins/NoTill.pdf [Retrieved February 12, 2019]
2 http://www.pgeconomics.co.uk/pdf/2016globalimpactstudymay2016.pdf [Retrieved February 12, 2019]
3 Ferguson, F. 1988. Long term effects of systemic pesticides on honey bees. Bee keeping in the year 2000: Second Australian and International Beekeeping Congress, Surfers Paradise, Gold Coast, Queensland, Australia, July 21-26, 1988. Editor: John W. Rhodes. Pages: 137-141.
4 Burgett, M. and Fisher, G. 1990. A review of the Belizean honey bee industry: Final report prepared at the request of The Belize Honey Producers Federation. Department of Entomology, Oregon State University, Corvallis, Oregon.
5 Thompson HM, Levine SL, Doering J, Norman S, Manson P, Sutton P, von Mérey G. (2014) Evaluating exposure and potential effects on honeybee brood (Apis mellifera) development using glyphosate as an example. Integr Environ Assess Manag. 2014 Feb 25. doi: 10.1002/ieam.1529.
6 http://www.fao.org/faostat/en/#data/QA [Retrieved February 12, 2019]
7 Inamine, Hidetoshi, Stephen P. Ellner, James P. Springer, and Anurag A. Agrawal. "Linking the continental migratory cycle of the monarch butterfly to understand its population decline." Oikos 125, no. 8 (2016): 1081-1091.
8 https://www.conanp.gob.mx/comunicados/MMENGLISH.pdf [Retrieved February 12, 2019]
9 https://www.epa.gov/ingredients-used-pesticide-products/draft-human-health-and-ecological-risk-assessments-glyphosate [Retrieved February 12, 2019]
10 https://www.efsa.europa.eu/sites/default/files/170523-efsa-statement-glyphosate.pdf [Retrieved February 12, 2019]
11 https://academic.oup.com/jnci/article/110/5/509/4590280 [Retrieved February 12, 2019]
12 https://www.who.int/foodsafety/jmprsummary2016.pdf?ua=1 [Retrieved February 12, 2019]
13 https://www.canada.ca/en/health-canada/news/2019/01/statement-from-health-canada-on-glyphosate.html [Retrieved February 12, 2019]
14 https://www.epa.gov/iris/reference-dose-rfd-description-and-use-health-risk-assessments [Retrieved February 12, 2019]
15 http://ec.europa.eu/food/plant/pesticides/eu-pesticides-database/public/?event=activesubstance.detail&language=EN&selectedID=1438 [Retrieved February 12, 2019]
16 https://www.fda.gov/NewsEvents/Newsroom/FDAInBrief/ucm622192.htm [Retrieved February 12, 2019]