The federal baby food litigation did not turn on whether heavy metals were in the food. It turned on how much of it a child was assumed to have eaten. On February 27, 2026, Judge Jacqueline Scott Corley granted in part and denied in part the defendants’ motions to exclude plaintiffs’ expert witnesses, and the reasoning is worth reading closely by anyone who thinks these cases are about contamination. Plaintiffs’ exposure case began with an infant dietician who built hypothetical menus — model diets estimating what a young child might eat. The court found the menus did not represent realistic consumption patterns and had no reliable scientific basis. Because the exposure scientist’s dose calculations rested on those menus, they went too. Because the epidemiologists and toxicologists rested on the calculations, their general causation opinions went as well. One opinion survived. The structural lesson is that in a toxic-exposure case the dose is not a detail, and a model diet is not a documented one.
The order of operations in a toxic tort
Before a court reaches whether a particular product hurt a particular child, it asks a narrower question: can this exposure cause this condition at all? That is general causation, and the court phased this litigation to resolve it first. General causation expert discovery closed on August 29, 2025. Cross-motions to exclude were filed on September 26, 2025, argued over several days, and closing presentations were heard on December 11.
Federal Rule of Evidence 702 is the gate. The party offering an expert must show, more likely than not, that the opinion rests on sufficient facts, reliable methods, and a reliable application of those methods to the facts of the case — and that it will help the trier of fact. Reliability and relevance are both required, and an opinion can fail on either.
Where it broke
To show that exposure from these products could cause the alleged injuries, plaintiffs had to establish a level of exposure worth analyzing. Their first witness on that question was an infant dietician who constructed hypothetical menus estimating baby food consumption for children roughly ages zero to three. The exposure scientist then converted those menus into dose and blood-lead estimates.
The menus do not represent realistic consumption patterns and do not evince a reliable scientific basis.
That single finding decided most of the motion. The menus were held neither reliable nor relevant to the general causation phase. The exposure calculations built on them were excluded for the same reason, and additionally because the court found the exposure assessment’s own principles and methods had not been reliably applied — the scenario was never scientifically validated.
The cascade
Expert opinions in a case like this sit on top of one another. When the bottom layer is removed, the layers above it lose their footing:
- The hypothetical menus — excluded. Not a realistic consumption pattern, no reliable scientific basis.
- The exposure calculations and blood-lead estimates — excluded. Built on the menus, and independently faulted for not validating the exposure scenario.
- The epidemiology and toxicology general causation opinions — excluded. They relied on the excluded calculations, and the court identified separate grounds as well.
- The biological plausibility opinion — not excluded. The court found this expert had applied a reliable scientific method.
The court also noted a gap in the literature plaintiffs were working from: no study had examined whether food of any kind can cause these conditions, which left the causation theory resting on extrapolation from studies of lead and arsenic exposure generally rather than from baby food specifically.
What survived, and what it is good for
The clinical neurologist offered to opine on the biological plausibility of lead and arsenic influencing the development of ASD and ADHD symptoms was not excluded. Plaintiffs carried their burden as to him. It is worth being precise about what that means: biological plausibility is an argument that a mechanism could exist. It is not, by itself, an opinion that a realistic exposure to these products caused these diagnoses. The opinion that had to do that work is the one that did not survive.
Two metals left the case
The amended master complaint had alleged that lead, arsenic, mercury and cadmium caused the plaintiffs’ ASD and ADHD. No expert testimony was offered on the effects of mercury or cadmium, and the court treated that theory as abandoned — plaintiffs dismissed their claims as to those two metals with prejudice. The federal litigation is now a lead and arsenic case. That is a narrowing worth knowing about, because public discussion of heavy metals in baby food still routinely names all four.
The transferable lesson
Defendants in exposure cases have learned to attack the dose rather than the chemical. It is the softest point in most plaintiffs’ cases, because the chemical is usually documented and the dose usually is not — consumption happened years ago, in a kitchen, without records. Reconstructing it is legitimate scientific work, but it has to be anchored in what the children actually ate rather than in what a child of that age might plausibly eat. That is the distinction the February order enforced, and it is the one any future attempt in this litigation will have to answer. For the underlying allegations, the brands named and where the federal proceeding now stands, see our page on toxic baby food claims.
This article is general information about how these cases work. It is not legal advice, it does not create an attorney-client relationship, and no two claims are alike. If something here sounds like your situation, the useful next step is a conversation about the facts.
