Environmental Litigation at an Inflection Point

Key Takeaways:

• Environmental litigation is at a moment of significant change, driven by shifting precedent, evolving agency policy, and complex exposure pathways that create uncertainty for plaintiffs and defendants alike.
• Federal preemption is increasingly central to pesticide litigation, particularly in mature mass-tort proceedings involving Paraquat and Roundup products, and its analysis requires case-specific attention rather than a standardized approach.
• Deregulation does not eliminate litigation. It redirects it toward administrative procedure, statutory authority, while private claims continue around drift, crop loss, and property damage.
• Biosolids contamination is opening a new pathway for PFAS-related claims, moving beyond factory discharge cases to product and beneficial-use programs affecting working farmland.
• The next mass-tort dockets may already be forming around chemicals like chlorpyrifos and atrazine, requiring monitoring of regulatory action, exposure pathways, and emerging plaintiff or defense coordination.

Environmental litigation is increasingly shaped by the interaction of changing precedent, shifting agency policy, and complex exposure pathways. Product-liability plaintiffs, regulated companies, farmers, landowners, and public-interest groups face moving targets while claims are developed. The result is uncertainty surrounding difficult- to-meet thresholds, proper defendants, causation, and federal regulation.

Preemption Moves to the Center of the Case

One source of uncertainty is the expanding importance of federal preemption in pesticide litigation. As discussed in the Environmental Law Institute’s analysis of preemption, procedure, and power, the Supreme Court’s treatment of the relationship between federal pesticide labeling requirements and state-law claims has consequences well beyond doctrine. Preemption can determine whether a case reaches fact discovery, expert testimony, or a jury.

This issue is particularly consequential in mature mass-tort proceedings involving Paraquat and Roundup, where failure-to-warn theories are central. Parties will likely want to consideration whether preemption may be treated as a standardized motion across every docket. The analysis may turn on the state-law duty asserted, relief requested, approved label, regulatory record, and timing of agency action. Counsel should consider ways to isolate those details early and build a record capable of appellate scrutiny.

Beyond existing pesticide dockets, claims intersecting with Environmental Protection Agency (EPA) requirements will invite renewed attention to whether they impose obligations that differ from, or add to, federal law.

Deregulation Does Not Mean an End to Litigation

An example of policy changes within the EPA creating a second front is the Dicamba litigation. Federal courts set aside earlier approvals, including a 2024 decision addressing the agency’s public participation process. The EPA subsequently reapproved Dicamba for genetically engineered cotton and soybeans, and farmers and conservation groups filed a new challenge to that reapproval.

Deregulation can redirect litigation rather than eliminate it. Challenges may migrate toward administrative procedure, statutory authority, or the agency’s evidentiary record. Private claims may continue to focus on drift, crop loss, property damage, or alleged personal injury.

Trifludimoxazin is another developing example. Environmental groups have challenged the EPA’s registration of the herbicide, describing it as a PFAS pesticide which has lasting effects on human health. The challenge alleges that the agency failed to adequately assess risks associated with food, water, worker exposure, wildlife, runoff, and spray drift. Whatever the ultimate disposition, the dispute shows how pesticide approval, PFAS persistence, and conventional contamination theories continue to be affected by each other.

Biosolids Expand the Contamination Map

Another area to watch is biosolids used as fertilizer. Claims by farmers alleging that PFAS-contaminated waste reduced land value or required destruction of property, illustrate a different pathway from the familiar factory-discharge case. The alleged contamination may arrive through a product or beneficial-use program, spread across working land, and create losses tied to soil, water, livestock, crops, and marketability.

These cases appear to be difficult to plead and prove. Potential defendants can include manufacturers, processors, distributors, treatment entities, or others in the chain; each may contest knowledge, duty, causation, and allocation. Early dismissal arguments may narrow theories even when a court has not resolved every issue on the merits. Litigators should expect intensive work on source identification, sampling methodology, historical records, fate and transport, and separating contamination-related losses from other economic pressures.

The biosolids context also encourages counsel to monitor adjacent theories carefully. Early speculation connecting waste applications to unrelated disease outbreaks should not be presented as established causation without reliable epidemiological and scientific support. Distinguishing a litigable hypothesis from a supported factual claim has proven to be a disciplined approach.

The Next Chemical Dockets May Already Be Forming

Finally, environmental litigators should look beyond the substances already dominating headlines. Recent commentary identifies chlorpyrifos and atrazine as pesticides to watch. The appropriate response is not to assume the next mass tort, but to monitor the ingredients of one: regulatory action, exposure pathways, scientific literature, enforcement activity, crop or property damage reports, and the emergence of coordinated plaintiff or defense teams.

The broader outlook is therefore neither simply pro-plaintiff nor pro-defense. Preemption may foreclose some claims, while contested approvals and new contamination pathways generate others. The litigator’s advantage will come from connecting doctrine, agency procedure, science, and damages before those issues harden into conventional wisdom. In an unsettled field, disciplined fact development, may generate pathways to overcoming this evolving litigation landscape.

Continue Exploring Environmental Litigation Trends

This article is part of EisnerAmper's Environmental Series, which explores how environmental litigation is evolving across fire, water, air, and soil.

For organizations navigating the operational and financial impact of environmental litigation, EisnerAmper's Settlement Administration and Forensic, Litigation & Valuation practices provide the fund administration, damages quantification, and expert-witness support these matters demand. Contact our team to learn more.