Potassium bicarbonate (also known as potassium hydrogen carbonate or potassium acid carbonate) is a colorless, odorless, slightly basic, salty substance. According to the U.S. Food and Drug Administration (FDA), potassium bicarbonate is "generally recognized as safe". There is no evidence of human carcinogenicity, no adverse effects of overexposure, and an undetermined . It is among the food additives encoded by European Union, identified by the initials E 501. Physically, potassium bicarbonate occurs as a crystal or a soft white granular powder. Potassium bicarbonate is very rarely found in its natural form, the mineral called kalicinite.