Many urban legends are framed as complete stories with plot and characters. The compelling appeal of a typical urban legend is its elements of mystery, horror, fear or humor.Often they serve as cautionary tales.ecause people frequently allege that such tales happened to a  friend of a friend  (FOAF), the phrase has become a commonly used term when recounting this type of story. Sometimes urban legends are repeated in news stories, or distributed by e-mail or social media.
We have mast cells in the stomach wall. Somastatain-which is produced from d cells in the stomach wall is a known mast cell activator. We also know stress-in particular substance p and CRH also cause mast cells to spill contents. Histamine which we know is a chemical constantly released.
Hydrogen cyanide, a poisonous gas that interferes with cellular respiration, was first used as a pesticide in California in the 1880s. Research at Degesch of Germany led to the development of Zyklon (later known as Zyklon A), a pesticide which released hydrogen cyanide upon exposure to water and heat.