Bayer removed glyphosate from residential Roundup to manage litigation risk. What replaced it is, on average, 45 times more toxic. The label doesn’t say that either.
This piece is a companion to The Shield, a four-part Old Guardian investigation into the legal, regulatory, and corporate architecture surrounding Roundup litigation, and to The Reviewer, which examines the EPA’s glyphosate cancer determination and what a federal court found when it looked closely at the methodology. Both are available at theoldguardian.ca. This piece stands on its own.
The Exit
On July 29, 2021, Bayer CEO Werner Baumann told investors why the company was removing glyphosate from its residential Roundup line. He did not reach for corporate euphemism. He was direct.
“More than 90% of the Roundup litigation claims Bayer has faced in recent years have come from the U.S. residential lawn and garden market business segment and is what led to the company deciding to abandon it. Let me be very clear that this decision is exclusively geared at managing litigation risk and not because of any safety concerns.”
Parse that statement carefully. More than 90 percent of tens of thousands of cancer claims came from residential users. Not the farmer with documented occupational exposure records. Not the licensed commercial applicator. The homeowner. The person who bought a bottle at a hardware store and sprayed their driveway or garden path on a spring weekend without a second thought. That person generated nine out of ten of Bayer’s cancer lawsuit claims.
Baumann’s stated reason for exiting that market was not that Roundup had been found unsafe for residential use. It was that continuing to sell it to residential users was generating too much litigation. The product, in Bayer’s own framing, was fine. The lawsuits were the problem.
The residential user was not informed of any of this. No letter. No recall. No shelf notice. No label change explaining why the product was being reformulated. The bottle that had sat on hardware store shelves for decades simply began appearing in a new version, distinguished from the old one by a small red bar reading “Exclusive Formula.”
What was inside the new bottle is the story this piece tells.
What Replaced It
In October 2024, Friends of the Earth reviewed Roundup products for sale at Home Depot and Lowe’s, the two largest home and garden retailers in the United States. The analysis found seven Roundup products still containing glyphosate on shelves alongside eight new reformulated products. The new products contained combinations of four replacement chemicals: diquat dibromide, fluazifop-P-butyl, triclopyr, and imazapic.
All four chemicals pose greater risk of long-term and reproductive health problems than glyphosate, based on the EPA’s own evaluation of safety studies -- not on Friends of the Earth’s independent assessment. The underlying data is the agency’s. The analysis is FOE’s. That distinction matters for sourcing purposes and is stated explicitly here.
The replacement chemicals have been linked to kidney and liver damage, reproductive and developmental abnormalities, birth defects, and allergic reactions affecting the eyes, skin, and respiratory system. Two of the four -- diquat dibromide and imazapic -- are banned in the European Union.
The worst of the four is diquat dibromide.
Diquat dibromide is present in every single new Roundup formulation. It is classified as a highly hazardous pesticide. It is 200 times more chronically toxic than glyphosate. The European Union banned it under Commission Implementing Regulation EU 2018/1532, effective June 30, 2019, following findings by the European Food Safety Authority of high risk to workers, bystanders, and residents. The UK, China, and several other countries followed with their own bans or severe restrictions.
The United States did not ban it. The EPA continues to approve it for residential consumer use. It is now the primary active ingredient in the product sold to the consumer who was, in Bayer’s own calculation, the source of nine out of ten cancer litigation claims under the previous formulation.
On average, the new Roundup formulations are 45.6 times more chronically toxic to human health than the glyphosate-based products they replaced, and 3.9 times more acutely toxic. Those figures come from the FOE analysis drawing on EPA safety study evaluations. Bayer disputed the analysis, calling it deeply flawed. The company did not identify which specific toxicity comparisons it contested, nor did it dispute that the underlying data source is the EPA’s own safety study evaluations.
The packaging is nearly identical to the old Roundup. The same green bottle. The same brand name. The same shelf position at the same retailers. A small red bar reading “Exclusive Formula” is the only visual signal that the product has changed. There is no requirement under FIFRA or any other federal law that Bayer inform consumers their product has been reformulated with chemicals the EPA rates as significantly more dangerous than what they previously bought. No label change was required. No consumer notification was mandated. The EPA approved the new labels. The new labels do not mention any of this.
The Shelf Problem
As of October 2024 -- the last verified shelf review -- seven glyphosate-containing Roundup products remained for sale at Home Depot and Lowe’s. Old stock is legally sellable until it’s gone. Bayer stopped producing glyphosate residential Roundup in 2023, but existing inventory has no mandated sell-by date and no pull date requirement. A consumer buying a Roundup product today may be buying old glyphosate stock, new diquat dibromide stock, or a product containing both -- and there is no reliable way to know which without reading the active ingredient list in fine print on the back label.
The garage shed compounds this problem significantly. Concentrated Roundup loses herbicidal effectiveness over time -- typically seven to eight years under optimal storage conditions, significantly less in the temperature fluctuations and partial seals of a typical residential shed. But herbicidal degradation and carcinogenic potential are two entirely separate biological mechanisms.
The surfactants and adjuvants that make glyphosate kill weeds quickly break down with age and poor storage conditions. The glyphosate molecule itself is chemically stable, non-volatile, and does not degrade in the presence of light or air. A bottle that has lost 40 percent of its weed-killing speed has not lost 40 percent of its glyphosate concentration. The consumer who compensates for reduced visible efficacy by using more product is not reducing their exposure to the compound of concern. They may be increasing it.
No label communicates this distinction. The “safe when used as directed” instruction assumes a fresh, properly formulated product applied under controlled conditions by a person following label directions precisely. It does not describe a three-year-old backyard shed bottle used by someone in shorts and sandals who applies extra product because the weeds aren’t dying fast enough.
And now the same problem applies to the replacement chemicals. The new diquat dibromide formulations are on shelves today. In three years they will be in sheds. In five years they will be the old stock that consumers compensate for with higher application volumes. The label will still not explain the difference between a product losing weed-killing speed and a product maintaining its full chronic toxicity profile. Because no label is required to say that. Because the EPA approved these labels. Because that approval, as The Reviewer documented, functions as the legal ceiling on what anyone can claim about what the label should have said.
What Was Always Available
The residential weed control problem that Roundup was marketed to solve has never required a synthetic chemical herbicide. The alternatives have always existed. They have simply not had a $500 million annual marketing budget.
Boiling water poured directly onto weeds in driveway cracks and patio joints kills on contact through cell membrane disruption, penetrates to the root system on shallow-rooted weeds, leaves zero chemical residue, and has been documented effective since before Roundup existed. No PPE required. No label. No exposure window. No degradation question. No litigation history. Cost: the energy to boil a kettle.
Horticultural vinegar at 20 percent acetic acid concentration -- significantly stronger than household vinegar -- kills broadleaf weeds on contact through the same mechanism. Available at garden centres. Not systemic, so deep-rooted perennial weeds may regrow from established root systems, but for the driveway crack and patio joint application that was Roundup’s primary residential use case it is functionally equivalent. The legitimate safety concern is eye and skin irritation from the acidity. That concern is addressed by gloves and eyewear -- the same PPE the Roundup label recommends and that almost nobody actually wears.
Iron-based herbicides -- like the Scotts product using FeHEDTA as its active ingredient -- are selective, meaning they target broadleaf weeds without harming grass, and are derived from a naturally occurring soil mineral. The isothiazolinone preservatives they contain warrant the same scrutiny as any chemical product. But the active ingredient mechanism is fundamentally different from systemic herbicides, and the regulatory history is substantially cleaner.
Corn gluten meal applied in early spring prevents weed seeds from germinating without any post-emergent chemical exposure. Zero toxicity concern for humans or pets. Applied once per season before germination, it dramatically reduces weed establishment in treated areas.
Flame weeding with a propane torch applied briefly to weed foliage causes cell rupture through rapid heating and is standard practice in certified organic agriculture. Effective for driveways, patios, and gravel paths. Zero chemical exposure. The legitimate concern -- fire risk in dry conditions -- is addressable in two label sentences.
None of these alternatives generate the recurring revenue that a branded chemical product sold at scale through national retail chains produces. Boiling water is free. Horticultural vinegar is a one-time low-margin purchase. Corn gluten meal is seasonal and inexpensive. A hori hori weeding knife lasts twenty years. Roundup, in either its original or reformulated version, generates reliable reorder revenue every season from a consumer base that has been trained by decades of marketing to reach for the bottle rather than the kettle.
The residential weed killer market was never built around what worked best for the homeowner. It was built around what generated the most reliable recurring revenue for the manufacturer. The reformulation to diquat dibromide did not change that logic. It updated it. Same shelf. Same brand. Same revenue model. Different chemical. And a fresh thirty-year clock on the litigation history.
Who Is Reviewing Diquat Dibromide
The question that ends this piece is the same question that runs through the entire investigation.
Glyphosate’s cancer litigation record spans thirty years. It generated more than 100,000 lawsuits, billions in settlements, and a Supreme Court ruling. The science linking it to non-Hodgkin’s lymphoma has been accumulating since the 1990s and was formally assessed by IARC in 2015. The EPA’s own Cancer Paper found effect estimates ranging from 1.3 to 1.5 increased NHL risk across the meta-analyses it reviewed. A federal appeals court found EPA’s methodology for dismissing that signal internally contradictory and legally unsupportable.
Diquat dibromide has been in consumer Roundup products since 2023. Its residential use history in the United States is three years old. There is no thirty-year litigation record. There is no IARC review. There is no epidemiological cohort study following residential users of diquat dibromide formulations for non-Hodgkin’s lymphoma or Parkinson’s disease or any other long-latency disease outcome. The science that would surface a problem, if a problem exists, has not had time to accumulate.
What exists right now is an EPA registration approval for diquat dibromide in consumer products. That approval was issued through the same registration review process The Reviewer documented in detail -- industry-submitted studies, a non-binding Scientific Advisory Panel, no enforcement timeline, no consequence for delay. The same process that produced the glyphosate cancer determination a federal court found defective is the process that produced the diquat dibromide approval the consumer is now buying at Home Depot.
The European Union found diquat dibromide posed high risk to workers, bystanders, and residents and banned it in 2019. The EU banned it seven years ago. It is now the primary active ingredient in every new residential Roundup formulation sold in the United States, in a product marketed to the population Bayer’s CEO identified as the source of nine out of ten cancer lawsuit claims under the previous formulation.
There is no requirement from the EPA that labels alert consumers to new chemicals or warn of increased risks when a product is reformulated. Drug companies cannot replace the aspirin in a brand-name pain reliever with a different compound and sell it in the same packaging without disclosure. Pesticide manufacturers can. And did.
Bayer did not solve the residential user’s problem. It solved Bayer’s problem. The residential user’s exposure continues, now with a chemical the EU banned seven years ago, through the same inadequate label framework, under the same regulatory approval process, with the same absence of consumer notification, and with the courthouse door now closed by a Supreme Court ruling that used that regulatory process’s output as its legal foundation.
The next question is whether Canada’s Pest Management Regulatory Agency reviewed diquat dibromide independently or mirrored EPA’s approval through the same procedural alignment that has historically governed its glyphosate conclusions. The Old Guardian intends to find out.
Editor’s Notes
Companion series: This piece is a companion to The Shield (four parts) and The Reviewer. All five pieces are available at theoldguardian.ca.
Primary sources: Bayer CEO Werner Baumann, investor call statement, July 29, 2021 (as reported by C&EN, AgWeb, and Modern Farmer, and consistent with Bayer’s published Five-Point Plan documentation); Friends of the Earth, “New Roundup, New Risks,” October 2024, drawing on EPA safety study evaluations for all toxicity comparisons (foe.org/resources/new-roundup-new-risks); Commission Implementing Regulation (EU) 2018/1532 of 12 October 2018, concerning the non-renewal of approval of diquat (EUR-Lex, effective 30 June 2019); European Food Safety Authority, Statement on non-dietary exposure on diquat, EFSA Journal 2018;16(4):5260; Friends of the Earth shelf review, Home Depot and Lowe’s, June through October 2024 (seven glyphosate products confirmed, eight reformulated products identified); Kendra Klein, Deputy Director of Science, Friends of the Earth, public statement October 2024.
Confidence tier: The Baumann quote is drawn from contemporaneous reporting across multiple outlets and consistent with Bayer’s own published documentation. The 45 times more toxic figure and the 200 times diquat dibromide figure are drawn from the Friends of the Earth analysis, which explicitly bases its toxicity comparisons on EPA’s own safety study evaluations, not on FOE’s independent scientific assessment -- this distinction is stated in the piece. The EU ban is confirmed through the primary EU regulation at EUR-Lex. The shelf review data reflects October 2024 findings; current shelf status may differ. The herbicidal degradation versus carcinogenic potential distinction reflects established chemical stability data for glyphosate and is not an assertion about human health outcomes. Bayer disputed the FOE analysis as deeply flawed but did not specify which toxicity comparisons it contested -- that response is noted in the piece. No claim in this piece asserts definitively that diquat dibromide causes cancer or that the new Roundup formulations will generate the same health outcomes as the old ones. The piece reports what is documented about the regulatory approval, the toxicity comparisons, the EU ban, and the absence of consumer notification requirements.
Ongoing monitoring: The Old Guardian will continue to monitor EPA’s diquat dibromide registration review, PMRA’s parallel approval status, and any emerging epidemiological research on residential diquat dibromide exposure outcomes.
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