An Outbreak of Food Borne Illness Due to Methomyl Pesticide Intoxication in Korea

On February 21, 2013, 6 elderly people collapsed abruptly after eating bean sprout bibimbab (boiled rice mixed with bean sprouts and seasoned with soybean sauce) at a countryside restaurant in the Chungbuk Province, Korea. Minutes after eating the meal, all of the patients lapsed into a state of stupor. Respiratory arrest developed in 2 patients; and one of two patients died of cardiac arrest. The autopsy identified methomyl and methanol in the deceased patient's gastric contents and in the remaining soybeanbean sauce seasoning. Five of the 6 patients ingested one spoonful of the soybeanbean sauce seasoning and survived, while one patient who died of cardiac arrest, ingested approximately two spoons. Symptoms of toxicity presented quickly in the subjects and progressed rapidly, including chest tightness, an unusual sensation in the pit of the stomach, dizziness, ataxia, and finally, collapse. Three patients who drank ethanol with the meal experienced only mild toxic symptoms. Our analysis of the clinical observations in these cases suggests that ingestion of methomyl pesticide and the additive toxicity of methanol may have been responsible for the intoxication.

Children's plasma cholinesterase activity and fatal methomyl poisoning.

There is a case of a couple who intentionally killed their children with methomyl insecticide. This was presented as our initial investigation of plasma cholinesterase (ChE) activity in Thai children. A hundred and five healthy Thai children 5-6 years of age, participated in the project. Their plasma was drawn to measure ChE activity. Mean +/- standard deviation of the children ChE was 7,417 +/- 1,620 U/L. The enzyme activity of the children was not significantly different between gender and parents' occupations. However, the mean of female ChE activity appeared to be lower than male ChE. Children whose parents were farmers appeared to have lower ChE activity than those whose parents were employees, merchants, government officers, unemployed parents, or private business owners. Two victims of child homicide were presented with ChE activity approximately 6 and 9 per cent of the average, considering healthy children. It was concluded that children's plasma ChE activity lower than 10 per cent of normal, could be a lethal indicator of anti-ChE insecticide poisoning.