Sodium azide poisoning in five laboratory technicians.

Five laboratory technicians accidentally ingested sodium azide, in quantities varying from 20 to 80 mg, in tea made from distilled water kept in a laboratory. Four had short-lived symptoms of dizziness, pounding heart, and faintness, while another developed a picture of myocardial ischaemia. He had further episodes of chest pains necessitating admission to hospital. These later symptoms were thought to be psychogenic in origin. Five laboratory technicians were eating lunch in a small storeroom adjacent to a laboratory. Three minutes after drinking a cup of tea, one of the girls felt faint with a pounding heart and fuzzy head. A few minutes later, two other girls who had also drunk a cup of tea had similar symptoms. The fourth technician, a man aged 24 who had had two cups of tea, fell to the floor with violent cramp-like pains in his chest radiating to the axilla and down both arms, with some tingling in his legs. No one associated his ill health with that of the previous three technicians who had left the room, and it was thought by the doctor who saw him at that time that he was suffering from myocardial ischaemia and he was sent to hospital. The fifth technician who had had half a cup of tea felt vagely unwell. The technician who filled the kettle from which the tea was made realised that she had used distilled water that had been treated with sodium azide (NaN3) to prevent bacterial growth. After two hours in the casualty department all the patients recovered. Three days later the male technician experienced a recurrence of the tightness and pains in his chest and fainted. He walked to the local hospital and after being reassured went home. He was apprehensive and unable to sleep. These symptoms persisted, and he was given diazepam and later relaxation therapy. Though some improvement took place the pain in his chest persisted. Barium meal showed an incompetent cardia and gastro-oesophageal reflux. Two months after the original incident he was admitted to hospital with chest pains. Repeat ECG was normal as were the fasting lipids. Six months later he was once more admitted to hospital for the 308 investigation of chest pain. Results of the investigations were normal. Environmental investigation Analysis of the distilled water/sodium azide solution with which the tea was made showed it to contain 214 mg/l and after boiling for ten minutes 220 …