Getting Roundup Out of Parks and Schools: Glyphosate Science, the 2026 Supreme Court Ruling, and What Communities Do

Over the past decade, parents, school groups, and residents in many communities have pushed local governments to stop spraying glyphosate-based herbicides such as Roundup in parks, playgrounds, and school grounds. Some succeeded: city councils and school districts adopted policies that favor organic or integrated pest management approaches, using mowing, mulching, hand weeding, and alternative products instead of synthetic herbicides. One widely shared story described a California mother who persuaded her city to change its practices.

These local efforts unfolded against a contentious scientific and legal backdrop. In 2015, the World Health Organization’s cancer research agency classified glyphosate as probably carcinogenic to humans, while the U.S. Environmental Protection Agency has long concluded it is not likely to be carcinogenic when used as directed. Thousands of lawsuits followed, culminating in a June 2026 Supreme Court decision. This article explains the science, the legal landscape, and how communities have changed the way they manage weeds in public spaces.

The Scientific Disagreement

The International Agency for Research on Cancer’s 2015 evaluation, summarized in The Lancet Oncology by Kathryn Guyton and colleagues, classified glyphosate as probably carcinogenic to humans (Group 2A) based on limited evidence in humans for non-Hodgkin lymphoma, sufficient evidence in experimental animals, and strong evidence for genotoxicity and oxidative stress. IARC assesses whether a substance can cause cancer under some circumstances, not the risk at typical exposure levels.

The EPA has repeatedly concluded that glyphosate is not likely to be carcinogenic to humans when used according to label directions, a conclusion shared by several other regulatory bodies, including the European Food Safety Authority. Critics argue that regulators relied heavily on industry-sponsored studies and gave less weight to formulated products, which contain other ingredients, and to exposures among heavy users such as agricultural workers and landscapers.

What Human Studies Show

A 2018 analysis of the Agricultural Health Study in the Journal of the National Cancer Institute by Gabriella Andreotti and colleagues followed 54,251 pesticide applicators in Iowa and North Carolina, 82.8 percent of whom had used glyphosate. Glyphosate was not significantly associated with any solid tumors or lymphoid malignancies overall, including non-Hodgkin lymphoma. Among the most highly exposed applicators there was a possible increased risk of acute myeloid leukemia that the authors said required confirmation.

A 2019 meta-analysis in Mutation Research by Luoping Zhang and colleagues, focusing on the highest exposure groups in each study, reported a 41 percent increased risk of non-Hodgkin lymphoma among people exposed to glyphosate-based herbicides. Critics of that analysis noted that choosing the highest exposure categories can inflate estimates and that the included studies varied in quality. The differing conclusions reflect genuine scientific uncertainty, especially about high, long-term occupational exposures.

How Much Glyphosate Are People Exposed To?

Glyphosate is the most widely used herbicide in the world, applied to crops, roadsides, lawns, and public spaces. Most people are exposed through diet, since residues occur in some grains, legumes, and other foods, especially crops sprayed shortly before harvest. A 2022 analysis of national survey data in Environment International by Maria Ospina and colleagues at the CDC measured glyphosate in urine samples from the 2013–2014 National Health and Nutrition Examination Survey and detected it in about 81 percent of people aged six and older, indicating that most of the U.S. population had recent exposure. Concentrations were generally low, and detection does not by itself indicate harm, but the findings show how widespread exposure is.

People who apply glyphosate professionally, such as farmers, landscapers, and groundskeepers, have much higher exposures than the general public. The plaintiffs in many lawsuits, including Durnell, were people who sprayed Roundup regularly over many years. For residents of communities where parks are sprayed, exposure depends on how and when products are applied and whether people contact treated areas before they dry.

The Legal Landscape

After IARC’s classification, tens of thousands of people who developed non-Hodgkin lymphoma sued Monsanto, which Bayer acquired in 2018, alleging that Roundup caused their cancers and that the company failed to warn them. Some juries awarded large verdicts, and Bayer agreed to multibillion-dollar settlements while continuing to contest other cases. In June 2022, according to the EPA, the Ninth Circuit Court of Appeals vacated the human health portion of the agency’s 2020 interim decision on glyphosate, and EPA later withdrew the interim decision while maintaining that its scientific findings remain valid. The agency says it is updating its human health risk assessment, with completion anticipated in late 2026.

On June 25, 2026, the Supreme Court decided Monsanto v. Durnell. According to the law firm Faegre Drinker, the case involved a Missouri man who said he used Roundup for about 20 years and developed cancer, and the Court ruled that his failure-to-warn claim was preempted because it would impose a labeling requirement different from what EPA required under federal pesticide law. The New Lede reported that the decision was 7–2, that Justice Ketanji Brown Jackson dissented, and that failure-to-warn claims in several thousand pending lawsuits likely cannot go forward. Legal analysts at Bergeson & Campbell noted that the ruling does not resolve the scientific debate about glyphosate; it clarifies that EPA, not state juries, decides when pesticide labels must change.

The Center for Food Safety, a critic of the decision, argued that it elevated corporate interests and emphasized that a federal court had found EPA’s earlier human health determination unlawful. The ruling shifts attention to EPA’s pending reassessment and to state and local policies on pesticide use in public spaces, which are not affected by the labeling question.

A Brief History of Roundup

Monsanto introduced Roundup in 1974, and glyphosate quickly became popular because it kills a broad range of weeds, breaks down relatively quickly in soil, and has low acute toxicity compared with many older herbicides. Its use expanded dramatically after 1996, when Monsanto introduced Roundup Ready crops, beginning with soybeans, genetically engineered to tolerate glyphosate so farmers could spray fields without harming the crop. Today glyphosate is used on corn, soybeans, cotton, canola, and sugar beets, as a pre-harvest drying agent on some grains and legumes, and in landscaping, roadsides, and home gardens. The patent on glyphosate expired in 2000, and many companies now sell glyphosate-based products.

Herbicide-Resistant Weeds

Heavy reliance on a single herbicide has led weeds to evolve resistance. A 2018 review in Pest Management Science by Ian Heap and Stephen Duke reported that 38 weed species had evolved resistance to glyphosate, across 37 countries and 34 crops, and the number has continued to grow. Resistant weeds such as Palmer amaranth have forced farmers to use additional herbicides, including older and more volatile ones such as dicamba, discussed in our article on dicamba drift. In public spaces, resistance is less of a concern, but it illustrates why diversified weed management is more sustainable than reliance on any single product.

Formulations and Other Ingredients

Roundup and similar products contain glyphosate plus other ingredients, including surfactants that help the herbicide penetrate plant leaves. Some research suggests that certain surfactants, such as polyethoxylated tallow amine (POEA), are more toxic to cells and aquatic organisms than glyphosate alone. The European Union banned POEA as a co-formulant in glyphosate products in 2016. Critics argue that regulators should evaluate complete formulations, which is what people are actually exposed to, rather than focusing mainly on glyphosate itself.

How Communities Reduce Herbicide Use

Local governments and school districts that have reduced glyphosate use generally adopt integrated pest management (IPM) or organic land care policies. IPM emphasizes preventing weed problems, monitoring, setting tolerance thresholds for weeds, and using the least hazardous effective methods, with synthetic pesticides as a last resort. Organic land care goes further by excluding synthetic pesticides on designated properties. Policies often prioritize areas where children play, such as playgrounds, sports fields, and school grounds.

Method	Where it works well	Trade-offs
Healthy turf practices (proper mowing height, overseeding, aeration)	Lawns and sports fields	Requires planning and consistent maintenance
Mulching	Planting beds, tree rings	Needs replenishing
Hand and mechanical weeding	Small areas, high-use sites	Labor-intensive
Hot water or steam weeding	Hardscapes, sidewalks	Equipment cost; repeated treatments
Grazing goats	Slopes, brush, large areas	Not suitable for every site
Organic-approved herbicides	Spot treatments	Often less effective on perennial weeds; some have their own hazards

Reducing herbicides often costs more in labor at first, and some managers report that organic methods work better on some sites than others. Invasive plant control in natural areas sometimes still relies on targeted herbicide use when other methods fail. Many communities therefore adopt tiered policies: no synthetic herbicides in playgrounds and school grounds, limited use elsewhere, and exceptions for specific invasive species or safety needs.

How Parents and Residents Can Advocate

Ask for records. Many cities and school districts keep pesticide application records and will share them on request.

Learn local rules. Some states require schools to notify parents before pesticide applications or to adopt IPM plans.

Attend meetings. City council, parks department, and school board meetings are where policies change.

Propose a pilot. Suggesting a trial of organic methods in one park or school allows comparison of costs and results.

Build coalitions. Groups of parents, health professionals, and gardeners can make a stronger case and help with volunteer weeding.

At Home

For home gardens, non-chemical approaches such as mulching, hand-pulling, and healthy lawn care reduce the need for herbicides. Homemade mixtures of vinegar, salt, and soap are widely shared online, but they have limits and risks, including harm to soil from salt and eye injuries from concentrated vinegar, as discussed in our article on natural weed killers. Anyone using glyphosate or other herbicides should follow label directions, wear recommended protective equipment, and keep children and pets away until the product has dried.

How Other Countries Regulate Glyphosate

Regulatory decisions on glyphosate vary internationally. The European Union renewed glyphosate’s approval in 2023 for ten years after the European Food Safety Authority found no critical areas of concern, though member states can restrict uses; some countries and cities in Europe limit its use in public spaces, gardens, or near schools. Other countries have restricted or debated restrictions on glyphosate at various times. These differences show that regulators weigh similar evidence differently and that policies often reflect public concern and precaution alongside scientific assessment.

Children and Public Spaces

Advocates for pesticide-free parks and schools often emphasize children’s greater vulnerability: children play on grass and soil, put hands in their mouths, and have developing organ systems. Many health organizations recommend minimizing children’s exposure to pesticides of all kinds as a precaution, regardless of debates over specific chemicals. Integrated pest management programs in schools aim to reduce pesticide use while controlling pests, and several states require schools to notify parents of applications or post signs. These approaches reduce exposure from all pesticides, not just glyphosate.

Key Terms

Glyphosate: The active ingredient in Roundup and many other herbicides.

IARC Group 2A: “Probably carcinogenic to humans.”

FIFRA: The Federal Insecticide, Fungicide, and Rodenticide Act, which governs pesticide registration and labeling.

Preemption: A legal principle under which federal law overrides conflicting state law.

Integrated pest management (IPM): A strategy that prevents and controls pests using multiple methods, with pesticides as a last resort.

What Bayer Says

Bayer maintains that glyphosate-based products are safe when used as directed, citing EPA’s conclusions and those of regulators in Europe, Canada, Australia, and elsewhere, as well as the Agricultural Health Study. The company has argued that the lawsuits rest on IARC’s hazard classification rather than evidence of risk at real-world exposures, and that a patchwork of state requirements for cancer warnings would conflict with federal labeling law, the argument the Supreme Court accepted in Durnell. Bayer has also stopped selling glyphosate-based Roundup to U.S. residential consumers, replacing it with products using other active ingredients, a decision it described as a way to manage litigation risk rather than a safety concern.

Key Facts at a Glance

IARC classified glyphosate as probably carcinogenic (Group 2A) in 2015. The Agricultural Health Study of 54,251 applicators found no association with non-Hodgkin lymphoma overall, while a 2019 meta-analysis reported a 41 percent higher risk among the most exposed. CDC data found glyphosate in the urine of about 81 percent of Americans tested in 2013–2014. In June 2022, the Ninth Circuit vacated the human health portion of EPA’s interim decision, and EPA says it expects to complete an updated assessment in late 2026. On June 25, 2026, the Supreme Court ruled 7–2 in Monsanto v. Durnell that federal law preempts state failure-to-warn claims.

The Bottom Line

Efforts to remove Roundup from parks and schools reflect real scientific uncertainty and a preference for precaution where children play. Scientific bodies disagree about glyphosate’s cancer risk, with stronger concerns for heavily exposed workers than for the general public. The 2026 Supreme Court decision limited lawsuits over missing cancer warnings but did not settle the science, and EPA’s pending reassessment will be closely watched. Communities that want to reduce herbicide use can adopt integrated pest management or organic policies, starting with playgrounds and schools, while recognizing the added labor and the occasional need for targeted treatments.

The Durnell Case in Brief

John Durnell, a Missouri man, said he sprayed Roundup for about two decades, including in parks and public spaces, before developing non-Hodgkin lymphoma. He sued Monsanto in Missouri state court, arguing the company should have warned users of cancer risks, and a jury found in his favor. Monsanto argued that federal law preempted the claim because EPA had approved Roundup’s label without a cancer warning, and the Missouri courts rejected that argument, deepening a split among courts in different states. The Supreme Court took the case to resolve that split. Its ruling in Monsanto’s favor means that, as long as EPA does not require a cancer warning, plaintiffs generally cannot win claims based solely on the absence of one, though other legal theories may still be pursued in some cases.

Glyphosate Residues in Food

Because glyphosate is used on many crops, low residues are found in some foods, particularly grains, legumes, and products made from them. Its use as a pre-harvest drying agent on crops such as oats, wheat, and some beans can leave higher residues than use earlier in the season. The EPA sets tolerances, or maximum residue limits, for glyphosate on foods, and federal monitoring has generally found residues below these limits. Advocacy groups have argued that tolerances are too high, especially for children. Consumers who want to minimize residues can choose organic products, since organic standards prohibit synthetic herbicides like glyphosate, though trace residues can occur through drift.

Common Myths

“The Supreme Court ruled glyphosate is safe.” The Court decided a legal question about labeling preemption, not the science of cancer risk.

“IARC found glyphosate causes cancer at normal exposures.” IARC evaluates hazard, not risk at typical exposure levels.

“Organic weed control is free of risks.” Some organic herbicides, such as concentrated acids, carry their own hazards.

“Cities cannot change pesticide practices.” Local governments control management of their own land.

Questions to Ask Your City or School District

Which pesticides are used on parks, playgrounds, and school grounds, and how often? Are applications posted in advance or announced to parents? Is there an integrated pest management policy, and who oversees it? Are there areas, such as playgrounds, where synthetic herbicides are not used? What would a pilot program of organic methods cost, and could volunteers help? Who should residents contact with concerns? Asking specific questions and requesting records can lead to productive discussions with parks staff, who often welcome community input and support.

What Landscape Managers Say

Parks and grounds managers often describe trade-offs in reducing herbicides. Organic and mechanical methods can require more staff time and equipment, and results may take longer, especially in established lawns with heavy weed pressure. Some managers report that healthier turf practices reduce weeds over time and that community acceptance of some weeds lowers maintenance demands. Others note that invasive species in natural areas sometimes require targeted herbicide treatments to protect native ecosystems. Successful programs often combine staff training, adjusted expectations, and phased transitions.

Further Reading

The EPA’s glyphosate page provides regulatory history and updates. The Agricultural Health Study publishes findings on pesticide exposures among farmers. Legal analyses of Monsanto v. Durnell explain the implications for future lawsuits. State extension services and pesticide reduction organizations provide guidance on integrated pest management and organic land care for parks and schools.

A Balanced View

Reasonable people can disagree about glyphosate. The weight of regulatory assessments finds low risk at typical exposures, while some epidemiological studies of heavily exposed workers and IARC’s hazard classification support caution. In public spaces where children play, many communities choose precaution because alternatives exist and the benefits of herbicide use there are modest. On farms, where glyphosate plays a larger economic role and alternatives can be costly or increase soil disturbance, the trade-offs are more complex. Recognizing these different contexts helps move discussions beyond all-or-nothing positions.

Further Reading on Safer Grounds Care

Many universities’ extension programs publish practical guides on integrated pest management for schools and parks, including weed thresholds, turf care calendars, and alternatives to synthetic herbicides. Organizations focused on children’s environmental health provide model policies for pesticide notification and reduction in schools. Reviewing these resources before approaching a city council or school board helps advocates propose realistic, well-supported plans.

What Happens Next

Several developments will shape the glyphosate issue in the coming years: EPA’s updated human health assessment, which could change labeling or use restrictions; remaining litigation based on legal theories not addressed in Durnell; possible congressional or state legislative action on pesticide labeling; and continued local policies on public land. Communities interested in reducing herbicide use do not need to wait for these outcomes, since decisions about parks and schools rest with local officials.

Protecting Yourself When Herbicides Are Used

When herbicides are applied in public spaces, simple precautions reduce exposure: observe posted signs and keep children and pets off treated areas until the product has dried or for the period stated on the label; wash hands after outdoor play; and remove shoes at the door to avoid tracking residues indoors. Workers and residents who apply herbicides should wear gloves, long sleeves, and eye protection, avoid spraying on windy days, and wash clothing separately. These measures are sensible regardless of the product being used and reflect standard label instructions.

For Readers Outside the United States

Glyphosate rules and public-space policies differ by country. Several European countries and many cities restrict or prohibit glyphosate use in public areas such as parks and playgrounds, while agricultural use generally continues under national and EU approvals. Readers elsewhere can check their national pesticide regulator and local government for rules governing public spaces, school grounds, and home use.

How to Read a Pesticide Label

Pesticide labels are legal documents under federal law, and using a product inconsistently with its label is a violation. Labels list the active ingredient and its percentage, signal words indicating acute toxicity (caution, warning, or danger), required protective equipment, restrictions such as re-entry intervals for treated areas, and environmental precautions such as avoiding application near water. Reading the full label before use, rather than relying on the front of the package, is the most important step for anyone applying herbicides at home, in community gardens, or on public land. Schools and parks departments can make labels and safety data sheets available to parents on request. Comparing the signal words and re-entry intervals of products in use is a practical starting point for discussions about switching to lower-risk methods or products in areas where children spend the most time.

Residents who want to track changes can also ask their local parks department to publish annual summaries of pesticide use, which several cities already do, making it easier to measure progress toward reduction goals over time and compare costs and results across different sites and seasons, and to identify where further reductions are feasible.

Frequently Asked Questions

Does Roundup cause cancer?

Scientific bodies disagree. IARC classified glyphosate as probably carcinogenic in 2015; EPA and other regulators concluded it is not likely carcinogenic at expected exposures. Studies of heavily exposed workers show mixed results.

What did the Supreme Court decide in 2026?

In Monsanto v. Durnell, the Court ruled 7–2 that federal law preempts state failure-to-warn claims requiring a cancer warning that EPA has not required.

Can my city stop spraying glyphosate in parks?

Yes. Local governments control their own land management practices, and many have adopted integrated pest management or organic policies.

Is EPA reviewing glyphosate again?

Yes. EPA says it is updating its human health risk assessment, with completion anticipated in late 2026.

Are organic weed control methods effective?

They can be, especially with good planning, but they often require more labor and may work better on some sites than others.

References

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2. Andreotti G, Koutros S, Hofmann JN, et al. Glyphosate Use and Cancer Incidence in the Agricultural Health Study. Journal of the National Cancer Institute. 2018;110(5):509–516. PMID 29136183
3. Zhang L, Rana I, Shaffer RM, et al. Exposure to glyphosate-based herbicides and risk for non-Hodgkin lymphoma: A meta-analysis and supporting evidence. Mutation Research Reviews in Mutation Research. 2019;781:186–206. PMID 31342895
4. U.S. Environmental Protection Agency. Glyphosate. epa.gov
5. Faegre Drinker. Supreme Court Decides Monsanto v. Durnell. June 2026. faegredrinker.com
6. The New Lede. US Supreme Court rules for Monsanto in case over pesticides and cancer warnings. June 2026. thenewlede.org
7. Bergeson & Campbell. Unpacking the Consequences of the Decision in Monsanto Company v. Durnell. July 2026. lawbc.com
8. Center for Food Safety. After Durnell: Why the Fight Against Pesticides and Their Health Harms Is Entering a New Chapter. July 2026. centerforfoodsafety.org
9. Ospina M, Schütze A, Morales-Agudelo P, et al. Exposure to glyphosate in the United States: Data from the 2013–2014 National Health and Nutrition Examination Survey. Environment International. 2022;170:107620. PMID 36368224
10. Heap I, Duke SO. Overview of glyphosate-resistant weeds worldwide. Pest Management Science. 2018;74(5):1040–1049. PMID 29024306

Last updated: October 6, 2026