Manganese (Mn) is a grayish-white transition metal with an atomic number of 25 in the periodic table of elements. Manganese is ubiquitous and occurs naturally in rocks and soil, often combined with other substances such as oxygen, sulfur, and chlorine. It can also be combined with carbon to form organic manganese compounds. Manganese is essential for normal physiologic functioning of animals and humans. Manganese is mostly used in metallurgical processes as a deoxidizing and desulfurizing additive and as an alloying constituent. Exposures to manganese can occur through metal fumes and manganese tetroxide, which is generated during the pouring of molten ferromanganese alloys. Health effects of manganese can be acute and chronic. Elimination of manganese exposures, occupationally and environmentally, should be the goal of any green ...