| toxicity summary | IDENTIFICATION AND USE: Sodium bicarbonate is a white crystalline powder or granules. It is used in manufacturing many sodium salts, as a source of carbon dioxide, ingredient of baking powder, and effervescent salts and beverages, in fire extinguishers, cleaning compounds. It is also used in analytical chemistry for pH adjustment. It is used in aquaculture as an anesthetic for fish in the United States. Sodium bicarbonate is used in the treatment of metabolic acidosis associated with many conditions. It is also used in veterinary medicine. HUMAN STUDIES: Risks of acute and chronic oral bicarbonate ingestion include metabolic alkalosis, hypernatremia, hypertension, gastric rupture, hyporeninemia, hypokalemia, hypochloremia, intravascular volume depletion, and urinary alkalinization. Abrupt cessation of chronic excessive bicarbonate ingestion may result in hyperkalemia, hypoaldosteronism, volume contraction, and disruption of calcium and phosphorus metabolism. The anticoagulant effects of sodium bicarbonate was investigated in fresh human whole blood obtained from normal healthy volunteers. Prothrombin and thrombin clotting time determination indicated that bicarbonate can interfere with the clotting process. ANIMAL STUDIES: Sodium bicarbonate was irritating to the rabbit eye. It was slightly irritating when tested on the skin of rabbits. Sodium bicarbonate was evaluated for teratological effects, maximum dose levels were as follows: mice, 580 mg/kg; rats, 340 mg/kg; and rabbits, 330 mg/kg. No effects were found in any of these species. The mutagenicity of sodium bicarbonate was assessed in Salmonella/microsome assays using Salmonella typhimurium strains TA 92, TA 94, TA 98, TA 100, TA 1535 and TA 1537 with metabolic activation, and it was negative. ECOTOXICITY STUDIES: Several histological anomalies, including increased incidence of necrotic cells, suggested that fish were adversely affected as a result of exposure to >450 mg NaHCO3/L. |