Plants such as broccoli, cauliflower, mustard, rapeseed, and horseradish contain organic compounds called glucosinolates. When the tissues of these plants are damaged, biologically active chemicals are produced. One of the most important compounds released is isothiocyanate (ITC). The pungency of horseradish and the spicy taste of hot mustard are caused by ITCs released when the tissues are macerated. At low concentrations ITCs are considered beneficial to human health. At high concentrations ITCs are general biocides that behave much like commercial pesticides. In fact, several commercial pesticides including Dazomet, Vapam, and Vorlex depend on an ITC as the active ingredient for pest control.