Molybdenum is an essential trace mineral in human nutrition. It is found in several tissues of the human body and is required for the activity of some enzymes that are involved in catabolism, including the catabolism of purines and the sulfur amino acids. Molybdenum is a transition metal with atomic number 42 and an atomic weight of 95.94 Daltons. Its symbol is Mo. Compounds of molybdenum are among the scarcer constituents of the earth's crust. It prevents and treats molybdenum deficiency. It has putative anticarcinogenic activity.