Toxicology: Beware the Man-of-War

The sunny Miami Beach morning seemed perfect for a swim. But from his lookout perch, Lifeguard Al Moore spotted some purplish blobs—Portuguese men-of-war were drifting shoreward. Moore chalked up a warning on a big blackboard at the Biltmore Terrace Hotel: "Danger—No Ocean Bathing Today."

Joseph C. Goodman, 73, a retired businessman from Stamford, Conn., either did not read or did not heed the warning. "He came out of the water staggering and falling," says Moore, "and he had tentacles all over his chest and his arms and legs." The third time he fell, Goodman was unconscious. Moore tried mouth-to-mouth breathing...