MASSIVE INGESTION OF THE HERBICIDE 2-METHYL-4-CHLOROPHENOXYACETIC ACID (MCPA)

Objective: To report the course of a massive ingestion of the herbicid e 2-methyl-4-chlorophenoxyacetic acid or MCPA (4-chloro-2-methyl pheno xy acetic acid) and to correlate plasma 2-methyl-4-chloropbenoxyacetic acid levels with symptoms of intoxication and treatment. Case Report: After intentional ingestion of the herbicide, 2-methyl-4-chlorophenox yacetic acid, a young man suffered bunting in his mouth, spasmodic pai n in the extremities and a severe hypotensive crisis. Plasma 2-methyl- 4-chlorophenoxyacetic acid concentration was 546 mg/L two hours after ingestion. Therapy by forced diuresis was ineffective until the urine was alkalinized (Day 4). This resulted in a rapid decline of the plasm a 2-methyl-4-chlorophenoxyacetic acid level to 6 mg/L and recovery of the patient.