Cobalt: A Toxic Metal

Cobalt has 27 protons, you know it has 26? Iron is a totally essential nutrient in very small quantities, but in large doses it is also toxic. Cobalt does not seem to occur in its elemental form in nature on Earth. It only occurs in ores with stuff like sulfur and arsenic. In long term, chronic cobalt exposure causes nerve damage that you'd maybe feel as tingling or pain or numbness in your fingertips and his feet.