Glyphosate’s climate dividend: Weedkiller reduces greenhouse pollution equal to taking 21.8 million cars off the road each year

By Graham Brookes
Published January 5, 2026 on the Genetic Literacy Project

Editor’s Note: This highly scientific research paper is summarized here, as it is too lengthy and with an extensive number of detailed charts to be offered here in its entirety. Go to The Genetic Literacy Project or the GM Crops & Food – Biotechnology in Agriculture and the Food Chain websites if you wish to download the entire paper.

This paper estimates the annual global carbon dioxide equivalent (CO2e) emissions from the manufacture, distribution and farm level use of glyphosate and estimates the annual contribution of glyphosate to reducing CO2e emissions through its role in facilitating a shift in farming production practices that are tillage-based into conservation tillage systems based on reduced and no tillage. Total annual global use of glyphosate is 749.27 million kg of active ingredient, applied to 646.11 million (spray) hectares. 

The CO2e emission generated from the manufacture, distribution and application of glyphosate in global agriculture is annually 9.76 billion kg. The total global combined annual fuel and soil carbon retention-related CO2e emissions of conservation tillage are a net reduction of −138.2 billion kg CO2e. This compares with +41.47 billion kg CO2e emissions if this area had been plowed with conventional tillage practices.

Therefore, conservation tillage practices provide a net reduction in combined annual fuel and increased soil carbon retention-related emissions of −179.67 billion kg CO2e relative to a conventional plow-based alternative production system. The total global combined annual fuel and soil carbon retention-related CO2e emissions of conservation tillage attributable to glyphosate is estimated at a net reduction of −41.93 billion kg CO2e. This compares with +13.01 billion CO2e emissions if this area had been plowed, providing a net reduction in combined fuel and soil carbon-related emissions attributable to glyphosate of −54.94 billion kg CO2e annually or the equivalent of taking 21.8 million cars off the road each year.

Literature Review

The literature highlights difficulties in estimating the precise contribution conservation tillage systems make to soil carbon sequestration levels and variations between the findings of different research methods reflect a variety of reasons. These include:

• Due to the duration  actors such as seasonal climate changes, land use and land management changes, 10 years is generally considered to be the minimum required.
• Looking at the depth at which soil organic carbon levels are measured, – there is widespread agreement that there is a positive relationship between conservation tillage and soil organic carbon (SOC) deposition in the top 15 cm of soil, though this diminishes below 15-30 cm.
• Soil type does not influence the effects of tillage on SOC stocks or concentrations from 0 to 15 cm, but does influence the effects deeper down (15-30 cm), SOC concentrations tend to be greater in sandy clay loam and silty clay soils under NT compared to tillage. 
• Latitude/Climate: differences in SOC between NT and tilled soils may be greater in arid rather than humid climates.
• The interaction of conservation tillage with other management practices such as crop cover, crop rotation or sequencing.
• If a specific crop area is in continuous conservation tillage crop rotation, the full soil carbon sequestration (storage) benefits described in most literature can be realized. However, if the conservation tillage crop area is returned to a conventional (plow-based) tillage system, a proportion of the soil organic carbon gain will be lost. This means that carbon storage only becomes permanent when farmers adopt a continuous conservation tillage system which, in turn, is highly reliant on effective weed control (typically herbicide-based).
• Some researchers argue that the level of soil organic carbon (SOC) reaches an equilibrium when the amount of carbon stored in the soil equals the amount of carbon released (the Carbon-Stock Equilibrium … CSE).This hypothesis implies that as equilibrium is reached, the rate of soil carbon sequestration may decline and therefore if equilibrium is being reached after 20 to 25 years of land being in conservation tillage, the subsequent rate of soil carbon sequestration may decline. This CSE hypothesis is, however, not universally accepted and other researchers question whether applying a CSE assumption in soil models is valid because of the scope for very old soils to continue to store carbon. For example, observed increases in SOC in the top 30 cm of soil of 1.37 Mg C ha⁻¹ year⁻¹ (1,370 kg of carbon (C) ha⁻¹yr¹) after 43 years of continuous maize under no tillage. This compared with a rate of 0.73 Mg C ha⁻¹ year⁻¹ (730 kg of C ha⁻¹yr¹) for maize grown using conventional tillage.
• The combined effect of temperature, moisture levels, soil texture and depth also affect SOC levels. Researchers identified that the depth of significant SOC additions with NT practices is highest for warm, dry, loamy, silty and clayey soils down to at 70 cm depth but only down to 5 cm for cool, dry, loamy, silty and clayey soils/tropical dry, sandy soils with the most temperature/moisture/soil texture combinations showing significant differences down to 30 cm depth. Across most of these temperature/moisture/soil type combinations, the “delta” SOC increase provided by the adoption of NT tillage estimated by this paper was within the range of 150 C ha⁻¹yr¹ to 540 kg C ha⁻¹yr¹.

Discussion

The net annual global impact of glyphosate use is providing a positive contribution to reducing global CO2e emissions arising from agricultural production of between −32.17 billion kg and −45.18 billion kg, equal to taking between 21.3 and 29.9 million cars off the road each year. The net annual global carbon storage with conservation tillage practices attributable to glyphosate is also equal to 30.6% of the total carbon storage associated with conservation tillage practices worldwide.

At an active ingredient level, the CO2e emissions associated with glyphosate manufacture, distribution and application by farmers is 13.03 kg CO2e per kg of active ingredient, balanced against a net CO2e storage associated with conservation tillage-related fuel savings and soil carbon sequestration attributable to glyphosate use of between −55.97 kg CO2e per kg of active ingredient and −73.33 kg CO2e of active ingredient, giving a net balance of between −42.94 kg CO2e per kg of active ingredient and −60.3 kg CO2e of active ingredient.

The point at which the conservation tillage-related fuel savings and soil carbon sequestration attributable to glyphosate cancels out the CO2e emissions associated with the manufacture, distribution and use of glyphosate is 13.03 Kg CO2e per kg of active ingredient. This is equal to between 5.4% and 7.1% of the total global combined annual fuel and soil carbon retention-related CO2e emissions saving from the global use of conservation tillage.

A recurring feature of the analysis is the dominance of the main grain and oilseed producing and exporting countries of North and South America in the adoption of conservation tillage practices and associated CO2e emission reduction as well as being the countries where the highest concentration of glyphosate use takes place. These countries account for 65% of global glyphosate use (in terms of active ingredient use), 72% of global CO2e emission reduction associated with conservation tillage practices and 79% of the share of these CO2e emissions reduction attributable to glyphosate use. This dominance of the main grain and oilseed exporting countries of North and South American countries is also closely associated with the widespread adoption of GM HT crops tolerant to glyphosate. 

In the first 20 years of the widespread use of this technology, tolerance to glyphosate was the dominant trait and glyphosate application dominated weed control in these production systems largely because of its broad-spectrum post-emergence activity, ease of use and cost effectiveness. Often it was used as the sole method of weed control in the first few years of GM HT crop adoption. For example, glyphosate accounted for over 80% of total active ingredient use on GM HT soybean crops in the USA in the late 1990s/early 2000s. As discussed earlier, GM HT (tolerant to glyphosate) technology also played a major role facilitating farmers adopting and staying in NT/RT-based conservation tillage production systems during this period.

This approach to weed control contributed to the evolution of weed populations predominated by resistant individual weeds and to weed shifts toward those weed species that are inherently not well controlled by glyphosate.

As a result, over the last 20 years, growers of GM HT crops have been using other herbicides (with different and complementary modes of action) in combination with glyphosate and in some cases adopting cultural practices (e.g., reverting to plowing) in more integrated weed management systems. In addition, GM HT crops tolerant to other herbicides (often stacked with glyphosate) have also become available from 2016 (notably dicamba, 2 4 D and glufosinate). This has likely reduced the year-on-year absolute levels of CO2e emission reductions from NT/RT-based conservation tillage agriculture facilitated by GM HT crops relative to several years ago in North and South America. The estimates presented in this paper do, however, take this factor of influence into account by using the latest available data on the adoption of conservation tillage areas, the share of glyphosate use in the pre plant/burndown phase of crop production cycles and on the share of GM HT crops that are only tolerant to glyphosate as distinct from GM HT crops tolerant to glyphosate plus other herbicides.

Read the original article on the Genetic Literacy Project »

As MAHA wages war on pesticides, the GOP is caught in the middle

By Rachel Frazin
Published January 13, 2026 on The Hill

The Make America Healthy Again (MAHA) movement’s crusade against pesticides is creating divisions in the Republican Party, as some members back the industry while others stand with MAHA activists.

As the MAHA movement, spearheaded by Health and Human Services Secretary Robert F. Kennedy Jr., gains power and influence within the GOP, efforts to limit liability for the pesticide industry are also growing on numerous fronts.

The issue is coming to a head in Congress, at the Supreme Court and on the state level, while other Republicans remain at the forefront of pushing pro-pesticide policies.

“I don’t know what these Republicans are thinking, because this is a really powerful conservative movement that doesn’t want this, and I think that they don’t have the memo yet that they need to be lining up with MAHA, because they really stand to lose their seat,” activist Kelly Ryerson said.

Republicans have traditionally been supportive of big business. But the MAHA movement is vocally skeptical of pharmaceutical, agriculture and chemical companies.

A key policy divide that has emerged is whether pesticide companies should have to disclose health impacts that are not officially recognized by the Environmental Protection Agency (EPA) — and whether they can be sued under state failure-to-warn laws for not doing so.

While bigger than any one pesticide, much of the debate is related to glyphosate, a key ingredient in Bayer’s Roundup weed killer that has been the subject of numerous lawsuits alleging cancer links.

“We as a company, for the past few years … have been working on a multipronged strategy to address litigation challenges. And for us … it’s about glyphosate and Roundup,” said Jess Christiansen, Bayer’s head of crop science communications.

“Farmers really rely on this product, and it’s so critical to food production and keeping production safe, effective and affordable,” Christiansen told The Hill. “We need to fight as best we can against the litigation industry.”

MAHA activists recently won the fight against a House appropriations provision that sought to prevent pesticides from carrying warnings on their label of health effects beyond those recognized by the EPA.

Critics warned that the measure could shield chemical companies from liability. Rep. Anna Paulina Luna (R-Fla.) is among them.

“This is completely wrong, and some of these pesticides are linked to cancer and infertility. Why on earth would we want to shield the companies? This is not benefiting the American people at all,” she wrote on the social platform X.

But other House Republicans, such as Rep. Mike Simpson (Idaho), who chairs the Appropriations Interior-Environment subcommittee, were among the provision’s supporters. 

“The language ensures that we do not have a patchwork of state labeling requirements,” he said last year.

Democrats have also opposed the measure.

While the provision did not make it into the minibus funding bill that’s expected to become law, the issue is expected to reappear. 

Asked whether the issue will appear again in this year’s anticipated farm bill effort, a House Agriculture Committee aide said Chair Glenn Thompson (R-Pa.) “intends to address the issue of pesticide labeling uniformity in Farm Bill 2.0.”

The aide said this will include updated language to “make it crystal clear that bad actors can still be penalized and held liable, while still bringing regulatory certainty to the marketplace.”

The aide did not specify how the update would accomplish both, and it’s unclear what would constitute a bad actor.

But they noted the EPA has “not only the authority, but the obligation, to act if new evidence emerges on the safety of a pesticide.”

Ryerson said she believes there’s a “disconnect” between Republicans and their voters amid the push to protect pesticides.

“There is a huge disconnect right now between the constituents and particularly these Republicans that have been in office for some time, where they have been able to just skirt by and make their corporate decisions that have injured human health,” she said. 

She said Republican lawmakers who have led the fight for pro-pesticide legislation should face primary challengers. 

“There are plenty of voters in the MAHA movement that are independent voters that would be happy to go and vote for the Democrat if they’re willing to address these things,” she added.

Meanwhile, the Supreme Court is weighing whether to take a case that similarly seeks to preclude failure-to-warn claims under the argument that any state-level requirements are preempted by the federal label.

Bayer asked the court to take the case, urging it to overturn a lower court ruling that it had to pay damages for failing to disclose information about the health impacts of Roundup.

The Trump administration has backed Bayer’s bid.

“We were very shocked that the White House would recommend taking it up and siding with Bayer,” said Ryerson, who uses the moniker of “The Glyphosate Girl” online.

“It is so counter to everything that the president has said in terms of creating safety around pesticides,” she added. “It was really disappointing to see that at that moment, the White House didn’t have the back of the MAHA moms.”

Bayer’s Christiansen said the company labeled its products appropriately under law and therefore should not be subject to the litigation. Roundup-related suits have already cost the company billions of dollars.

In 2020, the first Trump administration reapproved the use of glyphosate, citing “insufficient evidence to conclude that glyphosate plays a role in any human diseases.”

The ingredient is also still approved in the European Union. The World Health Organization in 2015 described it as “probably carcinogenic” to humans. 

The EPA is currently conducting an updated review of the chemical’s safety.

“EPA is conducting an updated human health risk assessment for glyphosate using rigorous scientific methods, with results expected this year,” an agency spokesperson said via email. “As new scientific information becomes available, EPA incorporates it into our assessments to determine whether additional safety considerations are warranted.”

Various chemical industry players have key roles at the EPA, but in recent weeks, the agency has made overtures toward MAHA amid discontent from activists. 

Bayer has maintained glyphosate does not cause cancer, and Christiansen noted that under law, the company is legally obligated to report credible findings of harm caused by their product. 

The company has pointed to research such as the federal government’s Agricultural Health Study. One 2018 publication under that project found no association between glyphosate and tumors overall, though it did find some evidence of increased risk of acute myeloid leukemia in people with high exposure levels.

However, a 2025 study found glyphosate caused various cancers in rats. 

Philip Landrigan, one of the authors of that study and the director of Boston College’s Program for Global Public Health and the Common Good said he’s “comfortable saying” glyphosate causes cancer.

Landrigan, who is also a physician, added that in the study, “There were no cancers in the animals that did not receive the chemical. There was a little bit of cancer in the animals that received a low dose of the chemical, and there was a lot of cancer in the animals that received a high dose of the chemical. In my mind, that’s cause and effect.”

At the same time, the liability shield issue is also taking shape at the state level. 

Republican governors in Georgia and North Dakota have already signed bills into law that shield pesticide makers from lawsuits. 

Similar legislation has been proposed in states including Tennessee, North Carolina, Iowa, Florida and Missouri.

The legislation’s proponents say at the state level, these laws will help provide guidance to the courts. 

“Even if a suit is brought forward into federal court, they are applying, in many cases, the state law, and so if something is not clarified in there about how a company satisfies their responsibility or their duty to warn, then it is up for the courts and the jury then to kind of define that via common law,” said Elizabeth Burns-Thompson, executive director of the Modern Ag Alliance, which was founded by Bayer but represents various players in the agriculture industry.

However, opponents argue the provisions could hamper accountability for dangerous products.

“It’s absolutely important for kids’ health that there is … some type of mechanism of accountability on an industry that sells poisons,” said Alexandra Muñoz, a toxicologist and activist working with the MAHA movement.

Read the original article on The Hill »

Everything You Need to Know About Roundup Lawsuits

Published January 14, 2026 on The Leader Reader

Roundup, an herbicide that has been used on a widespread scale around the world, has not only earned a reputation for being successful in destroying weeds but also for being linked to cancer. The main ingredient in Roundup herbicide, known as glyphosate, has been involved in a multitude of cases due to an increasing number of people claiming that it has brought about cancer in their lives, especially non-Hodgkin’s lymphoma. 

With all this happening in the wake of ongoing cases in court, it becomes essential for those involved to understand everything about the Roundup cases.

The Link Between Glyphosate and Cancer  

Glyphosate, the main ingredient in Roundup, was classified as a probable human carcinogen by the World Health Organization’s International Agency for Research on Cancer (IARC) in 2015. The Roundup lawsuits are based on allegations that exposure to glyphosate can lead to non-Hodgkin’s lymphoma, a type of blood cancer, with more than 7,000 claims pending. 

Many studies say glyphosate is linked to cancer. But the company that makes the chemical, Monsanto (a Bayer subsidiary), has consistently said otherwise, calling it safe and working as designed.

How Roundup Lawsuits Work

People who file Roundup lawsuits are usually people diagnosed with non-Hodgkin’s lymphoma (NHL) or other cancers, which they believe were caused by exposure to glyphosate. They file these claims as personal injury lawsuits. The makers of Roundup, which is an herbicide, were accused in these cases, mainly Monsanto, of failure to warn the users about possible cancer risks.

Oftentimes, plaintiffs allege that the company’s research disregards or misrepresents the data regarding the health hazards of glyphosate. Lawsuits also target the company’s alleged efforts to influence scientific findings or to play down risks in its marketing and labeling.

Types of Damages in Roundup Lawsuits

Plaintiffs in the Roundup lawsuit may be entitled to a wide array of damages if successful. You may be compensated or sued for damages, including medical costs, wages, and pain and suffering, among others. 

A defendant may also be subject to punitive damages if their conduct is particularly reprehensible. For instance, there may be punitive damages if the defendant deliberately withheld evidence about the dangers of Roundup or altered scientific studies. 

The amount of compensation one receives can vary widely based on the illness, the extent of exposure, and the legal area. Some cases have resulted in millions of dollars in settlements or jury awards, making them costly for everyone.

What to Do if You’ve Been Exposed to Roundup

An experienced lawyer can help you formulate the best legal strategy if you or someone close to you has been diagnosed with non-Hodgkin’s lymphoma or another cancer and you believe Roundup exposure is at fault. A lawyer who deals with product liability and personal injury cases can help you understand if you have a valid case and how to proceed next. 

Having your medical records and evidence of Roundup exposure on hand will strengthen your case. A legal expert can offer guidance regarding a possible settlement or whether to proceed with the case if it involves a trial.

Read the original article on The Legal Reader »

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