Chapman v. Proctor & Gamble Distribution, LLC

Marianne Chapman (plaintiff) used Fixodent denture adhesive for eight years and was later diagnosed with myelopathy, which she attributed to copper-deficiency myelopathy (CDM) caused by zinc in the product. She sued Proctor & Gamble (defendant), offering experts who testified Fixodent can generally cause CDM, plus a treating expert, Dr. Greenberg, who diagnosed her with CDM after the suit was filed and opined that her Fixodent use specifically caused it, using a differential-diagnosis method that is supposed to rule out other possible causes. Greenberg never considered whether Chapman's myelopathy might be idiopathic, hereditary, or multi-causal, and needed additional testing even after his initial diagnosis; P&G presented evidence Chapman had neurological problems since childhood. The district court excluded the expert testimony under Daubert as unreliable on both general and specific causation and granted summary judgment for P&G.