Inside a freezer in a research laboratory at the University of Washington are blood and blood plasma samples from 92 people who suffer from mysterious illnesses, including tremors, memory loss and severe migraine headaches. They are mostly pilots and flight attendants who suspect they’ve been poisoned in their workplace — on board the aircraft they fly. Clement Furlong, University of Washington professor of medicine and genome sciences, leads a team of scientists who have been collecting the samples for 2 ½ years.