HERBICIDE - FATAL AMMONIUM THIOCYANATE AND AMINOTRIAZOLE POISONING

Objective: To describe fatal herbicide poisoning with Radoxone TL comp osed of aminotriazole and ammonium thiocyanate. Case Report: A 54-year -old man was hospitalized because of unexplained coma with myoclonic j erks and vascular collapse. Despite symptomatic treatment with mechani cal ventilation and vascular filling, life-threatening shock occurred with oliguria, profound metabolic acidosis and cardiac arrest. Hyperch loremia (141 mmol/L) with reversed anion gap (-19) suggested interfere nce with chloride measurement caused by halogens (Br,F,I) or other ani ons such as thiocyanate. Eventually a weed killer, Radoxone TL contain ing ammonium thiocyanate, was found at the patient's house. Thiocyanat e and aminotriazole blood levels were 750 mg/L and 138 mg/L respective ly more than 12 hours after ingestion. After prolonged cardiopulmonary resuscitation, continuous venovenous hemodiafiltration was performed. Despite hemodynamic recovery the patient died 48 hours later of posta noxic coma. Conclusion: Aminotriazole, a systemic nonselective herbici de, is often associated with ammonium thiocyanate which enhances its a ctivity. Experimental studies and previous fatal cases suggest a predo minant toxicity of thiocyanate. Early diagnosis is important.