Richard Ferebee (plaintiff) worked for the Beltsville Agricultural Research Center. From 1977 to 1979, his work involved regularly spraying paraquat, an herbicide. On two occasions, Ferebee was directly exposed to paraquat. In 1977, Ferebee’s health began to decline. In 1984, Ferebee died from a lung disease called pulmonary fibrosis. Paraquat had been regulated by the U.S. government since 1966, because it was a known toxin. The paraquat that Ferebee sprayed was distributed by Chevron Chemical Co. (Chevron) (defendant). Chevron labelled paraquat with several warnings about the immediate and severe skin irritation that exposure could cause. By 1979, Chevron knew that paraquat could cause lung disease. It did not, however, know that skin exposure to paraquat could cause chronic injuries, in addition to acute ones, and that injuries could develop even after exposure to paraquat had ceased. Ferebee’s estate and children sued Chevron for wrongful death, alleging that Chevron’s labelling of paraquat failed to adequately warn Ferebee of paraquat’s dangers. At trial, doctors for Ferebee testified that they believed paraquat had caused Ferebee’s pulmonary fibrosis. Experts for Chevron testified, however, that there has never been evidence that paraquat causes chronic injury. A jury found in favor of the plaintiffs, awarding damages of $60,000. Chevron appealed, arguing that the jury could not have reasonably inferred that paraquat proximately caused Ferebee’s illness because the testimony of the parties’ experts conflicted. Additionally, Chevron argued that because it only had knowledge that paraquat caused acute injury, not chronic injury, Chevron did not have a duty to warn against lung disease. Finally, Chevron argued that inadequate labeling could not proximately cause Ferebee’s death because Ferebee did not read the label on the paraquat he used.