Ethylene Oxide Litigation Update: Georgia Court Clarifies Expert Testimony Standards

On October 31, 2025, the Georgia Court of Appeals issued an important decision in Sterigenics US LLC et al. v. Mutz et al., addressing how trial courts should evaluate expert testimony on general causation in toxic tort cases.

Background

Plaintiffs alleged that exposure to ethylene oxide (EtO) from Sterigenics’ Cobb County sterilization facility caused cancer and birth defects. At the trial level, the court excluded two of the plaintiffs’ experts, admitted one, and granted summary judgment on birth defect claims while allowing cancer claims to proceed. In doing so, the trial court applied a modified standard for expert admissibility, creating a “third category” between chemicals widely recognized as toxic and those that are not.

Appellate Court’s Analysis

The Court of Appeals vacated that ruling, holding that Georgia courts must apply the Eleventh Circuit’s McClain framework under Rule 702, which distinguishes between substances generally accepted as toxic and those requiring more rigorous proof. The appellate court emphasized that trial courts cannot create new categories beyond the two-tiered McClain framework.

Implications

This decision reinforces the need for methodologically sound expert testimony in toxic tort cases. For plaintiffs specifically, it clarifies the evidentiary burden and ensures consistency with federal standards.

The case is Sterigenics US LLC et al v. Mutz et al, 2025 Ga. App. LEXIS 512.