Barium bromate is a chemical compound of barium and bromine. Barium is a metallic alkaline earth metal with the symbol Ba, and atomic number 56. It never occurs in nature in its pure form due to its reactivity with air, but combines with other chemicals such as sulfur or carbon and oxygen to form barium compounds that may be found as minerals. Bromine is a halogen element with the symbol Br and atomic number 35. Diatomic bromine does not occur naturally, but bromine salts can be found in crustal rock. (5, 4)
belongs to the class of inorganic compounds known as alkaline earth metal bromates. These are inorganic compounds in which the largest oxoanion is bromate, and in which the heaviest atom not in an oxoanion is a lanthanide.
Barium is a competitive potassium channel antagonist that blocks the passive efflux of intracellular potassium, resulting in a shift of potassium from extracellular to intracellular compartments. The intracellular translocation of potassium results in a decreased resting membrane potential, making the muscle fibers electrically unexcitable and causing paralysis. Some of these barium's effects may also be due to barium induced neuromuscular blockade and membrane depolarization. Bromine is a powerful oxidizing agent and is able to release oxygen free radicals from the water in mucous membranes. These free radicals are also potent oxidizers and produce tissue damage. In additon, the formation of hydrobromic and bromic acids will result in secondary irritation. The bromide ion is also known to affect the central nervous system, causing bromism. This is believed to be a result of bromide ions substituting for chloride ions in the in actions of neurotransmitters and transport systems, thus affecting numerous synaptic processes. (6, 7, 1, 4)
Metabolism
Barium compounds are absorbed via ingestion and inhalation, the extent of which depends on the individual compound. In the body, the majority of the barium is found in the bone, while small amounts exists in the muscle, adipose, skin, and connective tissue. Barium is not metabolized in the body, but it may be transported or incorporated into complexes or tissues. Barium is excreted in the urine and faeces. Bromine is mainly absorbed via inhalation, but may also enter the body through dermal contact. Bromine salts can be ingested. Due to its reactivity, bromine quickly forms bromide and may be deposited in the tissues, displacing other halogens. (6, 4)
Toxicity Values
Not Available
Lethal Dose
1 to 15 grams for an adult human (barium salts). (9)
The health effects of the different barium compounds depend on how well the compound dissolves in water or the stomach contents. At low doses, barium acts as a muscle stimulant, while higher doses affect the nervous system, causing cardiac irregularities, tremors, weakness, anxiety, dyspnea, paralysisand possibly death. Barium may also cause gastrointestinal disturbances, damage the kidneys and cause decreases in body weight. Bromine vapour causes irritation and direct damage to the mucous membranes. Elemental bromine also burns the skin. The bromide ion is a central nervous system depressant and chronic exposure produces neuronal effects. This is called bromism and can result in central reactions reaching from somnolence to coma, cachexia, exicosis, loss of reflexes or pathologic reflexes, clonic seizures, tremor, ataxia, loss of neural sensitivity, paresis, papillar edema of the eyes, abnormal speech, cerebral edema, delirium, aggressiveness, and psychoses. Bromate is also a potential carcinogen. (4, 8, 5, 6, 7)
Symptoms
Ingesting excess barium may cause vomiting, abdominal cramps, diarrhea, difficulties in breathing, increased or decreased blood pressure, numbness around the face, and muscle weakness. High levels may result in changes in heart rhythm or paralysis and possibly death. Bromine vapour causes irritation and direct damage to the mucous membranes. Symptoms include lacrimation, rhinorrhoea, eye irritation with mucous secretions from the oropharyngeal and upper airways, coughing, dyspnoea, choking, wheezing, epistaxis, and headache. The bromide ion is a central nervous system depressant producing ataxia, slurred speech, tremor, nausea, vomiting, lethargy, dizziness, visual disturbances, unsteadiness, headaches, impaired memory and concentration, disorientation and hallucinations. This is called bromism. (6, 7, 4)
Treatment
EYES: irrigate opened eyes for several minutes under running water.
INGESTION: do not induce vomiting. Rinse mouth with water (never give anything by mouth to an unconscious person). Seek immediate medical advice.
SKIN: should be treated immediately by rinsing the affected parts in cold running water for at least 15 minutes, followed by thorough washing with soap and water. If necessary, the person should shower and change contaminated clothing and shoes, and then must seek medical attention.
INHALATION: supply fresh air. If required provide artificial respiration.
