By Martin Bricketto

Law360, New York (June 02, 2011, 6:55 PM ET) -- The Third Circuit on Thursday backed the exclusion of expert testimony in a Pennsylvania exterminator's lawsuit claiming Dow AgroSciences LLC's Dursban insecticide products gave him non-Hodgkin's lymphoma, affirming a district court ruling that doomed the plaintiffs.

A three-judge panel found that the district court did not err in excluding the report prepared by pathologist Dr. Bennet Omalu for plaintiffs Robert T. Pritchard Sr. and his wife, Elizabeth, knocking down arguments that the lower court improperly applied federal common law rules and that a jury should have...