Up to now, each article in this series exploring the legal claims commonly raised by plaintiffs in pesticide injury cases has focused on one single claim. Negligence, design defect, and failure to warn are all legal arguments raised in nearly every pesticide injury lawsuit. The previous articles in this series examined each of these claims in detail. This last article will focus on legal claims that are not as frequently argued in pesticide injury lawsuits, but are still important.

Breach of Warranties

Plaintiffs in pesticide injury cases will sometimes file claims for breach of warranties. While most of the claims raised by pesticide injury plaintiffs are tort claims, breach of warranties claims are based in contract law.

In general, a breach of warranty claim asserts that the defendant has breached a contractual duty owed to the plaintiff. In a products liability case, breach of warranties specifically argues that the defendant violated a guarantee that the product will perform in a particular way or according to a specific standard. Breach of warranties claims are typically divided into two general categories: breach of implied warranties and breach of express warranties. Plaintiffs in pesticide injury lawsuits typically raise breach of implied warranty, but breach of express warranty claims have also been filed.

According to the Uniform Commercial Code, the set of laws governing the sales of goods in the United States, an express warranty is “any affirmation of fact or promise made by the seller to the buyer which relates to the goods and becomes part of the basis of the bargain[.]” U.C.C. § 2-313(1)(a). In other words, an express warranty is any promise that a seller makes to a buyer about the product they are purchasing through overt words or actions that then becomes part of the sales contract. For example, if a seller makes an oral statement to a buyer that the product they are purchasing should last for at least five years, and the buyer relies on that statement in purchasing the product, the statement becomes an express warranty. If the product ceases to work within a year, the seller could be in breach of that warranty. An express warranty can be established through writing, advertisements, or through demonstrations by sales representatives. In order for a plaintiff to succeed on a breach of express warranty claim, they will need to show that the defendant made the warranty, that the product failed to perform as promised by the warranty, and that the plaintiff was harmed as a result of that failure.

Implied warranties are promises made by a seller to a buyer that the product will not harm the buyer when used for its intended purpose. Unlike express warranties, implied warranties are not promises explicitly made by the seller, but instead are an implicit part of the buyer’s purchase. There are two types of implied warranties: implied warranty of merchantability and implied warranty of fitness. To satisfy the implied warranty of merchantability the product must be “fit for the ordinary purposes for which [it is] used.” U.C.C. § 2-314(2)(c). To satisfy the implied warranty of fitness, the product must be fit for the purpose that the buyer purchased it for if the seller was aware of the purpose at the time of sale. U.C.C. § 2-315. While both implied warranties are aimed at ensuring the product purchased by the buyer performs as expected, the warranty of merchantability requires the product to be fit for all its intended functions while the warranty of fitness requires the product to be fit for the specific function that the buyer purchased it to perform.

Plaintiffs in pesticide liability cases typically argue that the defendants breached the warranty of implied merchantability. In order to prove breach of the implied warranty of merchantability, a plaintiff must show that: the plaintiff bought a consumer good that was either sold or manufactured by the defendant; at the time of purchase the defendant was in the business of selling that consumer good; the consumer good was not fit for its ordinary purpose; the plaintiff was harmed; and the defendant’s breach was a substantial factor in causing the harm. To prove breach of the implied warranty of fitness, a plaintiff must show that the seller knew or had reason to know the particular purpose for which the buyer had purchased the goods, and that the buyer was relying on the seller’s judgement to made the purchase.

In Hardeman v. Monsanto Co., No. 4:16-cv-00525 (N.D. Cal.), one of the earliest glyphosate injury lawsuits to be filed, the plaintiff claimed that the defendant breached both the warranties of merchantability and fitness. According to the plaintiff, although the defendant knew that using Roundup for its intended purpose would pose serious health risks to consumers, the defendant claimed that its Roundup products could be safely used to accomplish that purpose. The plaintiff argued that because he relied on the defendant’s assurances of safety to purchase and use the Roundup products that caused him to become seriously injured, the defendant breached the warranties of merchantability and fitness.

Other pesticide injury plaintiffs that have raised breach of implied warranty claims make similar arguments. For example, the plaintiff in Hoffman v. Syngenta Crop Protection, LLC, No. 17-L-517 (Ill. Cir. Ct.)  argued that the defendant had breached the warranty of merchantability by selling its pesticide paraquat despite knowing that using the pesticide in its intended manner for its intended purpose could cause users to develop neurological damage.

At the moment, none of the five pesticide injury lawsuits that have gone to trail brought breach of warranty claims before the jury. Of those five lawsuits, each of the plaintiffs raised breach of warranty claims in their initial complaints, but at trial chose to focus on other claims such as failure to warn or design defect. Until a pesticide injury plaintiff brings a breach of warranties claim before a jury, it is difficult to know how courts will treat those claims.


Pesticide injury plaintiffs will occasionally raise nuisance claims in their complaints. Nuisance is a tort that describes an injury to a person’s right to the undisturbed enjoyment of their property. Generally, nuisance claims are divided into two categories: private nuisance, and public nuisance.

A private nuisance describes an interference with a plaintiff’s enjoyment of their own property. For example, a property owner who frequently plays loud music late at night that prevents neighboring property owners from sleeping may be liable for private nuisance. In order to support a claim of private nuisance, a plaintiff must show three things: that the plaintiff either owns the land being interfered with or has the right to possess it; that the defendant acted in a way that interfered with the plaintiff’s enjoyment or use of the land; and that the defendant’s interference was both substantial and unreasonable.

Similar to private nuisance, public nuisance occurs when a party unreasonably interferes with a right shared by the general public. Most states have codified public nuisance, and as a result the exact definition can vary across jurisdictions. However, for the most part something will be considered a public nuisance if it threatens public health, safety, or welfare. For example, polluting a public waterway so that it is no longer safe to swim in would likely be considered a public nuisance.

Pesticide injury plaintiffs do not tend to raise nuisance claims nearly as often as other tort claims like negligence or failure to warn. However, multiple plaintiffs who had filed lawsuits alleging that use of the pesticide paraquat had caused them to develop Parkinson’s disease raised public nuisance claims against the defendant. In Hoffman v. Syngenta, one of the earliest paraquat lawsuits, the plaintiff claimed that the defendant had committed a public nuisance by manufacturing and distributing a product that did not maintain a “healthful environment” when used. Other paraquat lawsuits, made similar claims.

In 2021, all active pesticide injury claims involving paraquat were combined into a multi-district litigation (“MDL”).  An MDL is a civil court procedure that involves taking active cases that have been filed in various jurisdictions and transferring them to one court. The cases must have one or more issues in common, and will typically involve the same defendant. Typically, an MDL will be used to conduct pre-trial proceedings after which each case in the MDL will separately proceed to trial. After the on-going paraquat lawsuits were consolidated into an MDL, the defendant filed a motion asking the court to dismiss a variety of the claims raised by plaintiffs, including the claims of public nuisance. The defendants argued that public nuisance claims are inappropriate in cases where the plaintiffs are challenging a product instead of something the defendant did to create a public nuisance. In response, the plaintiffs claimed that the defendant created a public nuisance by advertising and promoting a product it knew would be dangerous to the public health. Ultimately, the court agreed with the defendant and dismissed the claims.

According to the court, the paraquat plaintiffs had failed to prove the elements of their public nuisance claims. In most jurisdictions, plaintiffs will need to show that a defendant has interfered with a right common to all members of the general public in order to prove a public nuisance claim. Because paraquat is a restricted use pesticide that can only be purchased and used by persons authorized to do so, the court determined that plaintiffs could not show harm to the general public. Therefore, the court dismissed the claims.

While it is possible that future pesticide injury plaintiffs may be able to successfully argue public nuisance claims, so far, those claims have tended to fail.


While claims of fraud are not universally raised in pesticide injury litigation, they have been raised by plaintiffs claiming that use of the glyphosate-based pesticide Roundup caused them to develop cancer. For example, both the class action plaintiffs that filed a complaint in In re: Roundup Products Liability Litigation, No. 3:16-md-02741 (N.D. Cal.) , and the plaintiff in Stephens v. Monsanto Co., No. CGC-20-585764 (Cal. Sup. Ct.) which was filed in state court raised fraud claims in their complaints. Although the claims did not make it to trial, they are still worth examining.

In a product liability lawsuit, plaintiffs will raise fraud claims to argue that the defendant attempted to conceal a defect with its product, and that doing so caused or contributed to the plaintiff’s injuries. Although many states have codified the elements of fraud so that what a plaintiff must show to prove a fraud claim can vary across jurisdictions, in general a plaintiff will need to demonstrate the following: that the defendant made certain factual statements about the product, that those statements were not true, that the defendant knew the statements were not true, that the defendant made those statements so that the plaintiff would buy the product, that it was reasonable for the plaintiff to rely on the defendant’s statements, and that the plaintiff was injured as a result of the defendant’s false statements.

Pesticide injury plaintiffs that raised claims of fraud argue that the defendant pesticide manufacturers made false statements about the safety of their pesticide products in order to convince the plaintiffs to buy those products. The plaintiffs then relied on those statements to purchase pesticides, and were subsequently injured by products they had been told were safe to use. With regards to Roundup, plaintiffs in In re: Roundup Products Litigation and Stephens v. Monsanto pointed to advertising statements made by the defendants that Roundup up is “practically non-toxic,” and “safer than table salt” to support their claims of fraud. The plaintiffs claim that if the defendants had warned consumers about the safety risks of using Roundup in their promotional materials or in other information presented to the public, then the plaintiffs would have used a different product.

The class actions plaintiffs in In re: Roundup Products Litigation ultimately reached a settlement agreement with the defendant without a judge or jury ever making a ruling on the fraud claims. However, in Stephens v. Monsanto, a judge issued a summary judgement order resolving the plaintiff’s fraud claims in favor of the defendant. Summary judgement is a pretrial procedure where the court rules on a claim based purely on the facts and arguments before the court without going to trial. Based on the facts and evidence presented to the court in Stephens v. Monsanto, the judge found that the defendant was not liable for fraud because fraud applies to dealings between two specific parties, not dealings between one party and the public at large. In order to prove fraud in California, the state where the plaintiffs filed their claims, the defendant must have a duty to disclose the whole truth to the plaintiff. That relationship typically arises from a transactional relationship where the plaintiff and the defendant directly interact. Because the plaintiffs in Stephens v. Monsanto never directly interacted with the defendants, and only heard statements about Roundup through television advertisements released to the public at large, the court concluded that the plaintiffs could not prove their fraud claims.

While it is possible that a court or a jury in the future could find a defendant pesticide manufacturer liable for fraud, that has yet to happen during the current trend of pesticide injury lawsuits.


This series has explored the various claims commonly raised by plaintiffs in pesticide injury lawsuits. Since 2016, these lawsuits have been on the rise, with plaintiffs having various success before judges and juries. As these lawsuits continue to be filed, it is important to understand what claims plaintiffs are raising and why they are raising them. Despite the Supreme Court declining to consider whether federal law preempts of the one key arguments made by plaintiffs, the debate over preemption appears far from over. At the moment, the current trend of pesticide injury lawsuits seems likely to continue.


To read the complaint in Hardeman v. Monsanto Co., click here.

To read the complaint in Hoffman v. Syngenta Crop Protection, LLC, click here.

To read the complaint in In re: Roundup Products, click here.

To read the complaint in Stephens v. Monsanto Co., click here.

To read the previous post in this series, click here.

To read the text of FIFRA, click here.

For more resources on pesticide regulation from the National Agricultural Law Center, click here.