Nature
- Barium carbonates is an inorganic poison.
- It is also known as witherite.
- It is a white amorphous powder.
- It is white solid precipitated form which results from the reaction between barium hydroxide and urea solution.
- It is toxic in nature or to human beings.
- It is poorly soluble in water but soluble in most of the acids.
- The chemical formula of Barium carbonate is BaCO3.
Uses
- It is used as rat poison or rodenticide.
- It is used in ceramics.
- It is also used in paints rubber and plastics.
- It is used in manufacturing enamels, glazes, bricks etc.
- It is also used as welding electrodes.
Fatal Dose
The fatal dose for Barium carbonate is about 60 to 70 mg/kg.
Fatal Period
The fatal period for Barium carbonate is 12 hours.
Mode of Action
● Hypokalemia and neuromuscular blockade.
● The rapid onset of the marked Hypokalemia so characteristic of barium intoxication is due to sequestering of potassium by muscle cells. Barium clogs the exit channel for potassium ions in skeletal muscle cells.
● Barium stimulates striated, smooth, and cardiac muscle resulting in violent peristalsis, arterial hypertension and arrhythmias.
Sign and Symptoms
For Gastrointestinal Tract
- Salivation
- Vomiting
- Severe abdominal pain
- Diarrhoea.
For Central Nervous System
- Mydriasis
- Paraesthesias
- Depressed tendon reflexes
- Headache
- Confusion
- convulsions.
For CVS (central venous catheter)
- Hypertension
- cardiac arrhythmias
- premature ventricular complexes
- ventricular tachycardia
- Bradycardia
- Ventricular fibrillation asystole/fibrillation.
For LMS
- Myoclonus
- Myalgia
- Cramps
- Dysarthria
- Flaccid quadriplegia.
For Respiratory System
- Pulmonary oedema
- Respiratory failure.
- Hypokalaemia
- Metabolic and respiratory acidosis, and renal failure are commonly reported.
- Quadriplegia is usually the result of severe hypokalaemia.
- constipation,
- Appendicitis
- Bowel perforation
- Peritonitis and proctitis
- ECG abnormalities have been reported.
- Dyspnoea,
- Hypoxaemia.
- Allergic reaction.
Treatments
► Gastric lavage should be administered. For lavage, 5 to 10 grams sodium sulfate can be added to the solution.
► Emesis may be effective.
► Monitor cardiac rhythm and serum potassium. Cardiac arrhythmias usually respond to potassium administration. If not, consider lignocaine, amiodarone, or procainamide.
► IV fluids (liberally, to flush out barium by diuresis). Administer 0.45% NaCl in D5W and a diuretic such as intravenous furosemide (1 mg/kg to a maximum of 40 mg/dose) to obtain a urine flow of 3 to 6 ml/kg/hr. Saline and furosemide forced diuresis has been reported to enhance barium elimination. If initial hydration is necessary, administer 0.45% saline to which sodium bicarbonate has been added to bring to isotonic 80 mEq/L at 20 to 30 ml/kg/hr for the first few hours.
► 30 grams of magnesium sulfate through a nasogastric tube (250 mg/kg for children). It precipitates the compound ingested into insoluble barium sulfate. In the past intravenous magnesium sulfate was recommended. This should be avoided because renal injury may result due to intrarenal precipitation of barium carbonate.
► Treat hypokalemia with potassium infusions (up to 250 mEq administered over 24 hours has been effective).
► Haemodialysis.
► Mild to moderate allergic reactions to barium sulfate administration can be managed with antihistamines, with or without inhaled beta agonists, corticosteroids or adrenaline.
► Treatment of severe anaphylaxis necessitates oxygen supplementation, aggressive airway management, adrenaline, ECG monitoring, and IV fluids.
Test for Detection or Forensic Examination
● X-ray of abdomen.
● Blood barium level.
● Flame Test- If barium present then gives green color to solution.
● For barium ions test – Add 10 drops of the toxicological sample to test tube. After that add 20 drops of ammonium sulfate and mix with a glass stir rod. If white precipitate form then it is indicative of barium.
● Carbonate Test
Post-Mortem Aspects
- Hemorrhagic gastritis and duodenitis.
- Pulmonary oedema.
Medico Legal Aspects
● Most cases are accidental, usually the result of mistaken identity, when a soluble barium salt is administered for a “barium meal” instead of the insoluble barium carbonate.
● Barium salts are sometimes also mistakenly ingested in place of Epsom salt, Glauber’s salt, or even common salt. Inhalation of a “barium meal” can produce granulomas in the lungs.
● A few cases of mass poisonings have been reported.
● Suicidal and homicidal cases are sporadically reported.
● Barium carbonate is used as rat poison.
References
- Dr. K.S. Narayan Reddy. The essential of forensic medicine and toxicology.34th edition.
- VV Pillay. Modern medical toxicology.4th edition.
- R.K.Sharma. Concise textbook of forensic medicine and toxicology. 3rd edition.
