title: Acute poisoning with phosphamidon: determination of dimethyl phosphate (DMP) as a stable metabolite in a case of organophosphate insecticide intoxication.
abstract: Many organophosphate pesticides (OP) such as phosphamidon are unstable in aqueous solutions and especially in blood in the presence of esterases. In a case of intoxication, the phosphamidon concentration in serum decreased from 10 mg/L to 4.4 mg/L after storage at -20 degrees C for six months; nearly complete degradation was observed after three years. Dimethyl phosphate (DMP) is a metabolite of phosphamidon, mevinphos, dicrotophos, monocrotophos, dichlorvos, and trichlorfon. A gas chromatographic-mass spectrometric method with deuterated DMP-d6 as internal standard for the determination of DMP in biological material was validated. DMP was found in all of the patient's samples (3.9 and 4.9 mg/L in blood, 33.5 and 50.4 mg/L in urine, and 8.1 mg/L in gastric fluid), even after storage at -20 degrees C for up to 3 years. No hints for a degradation of DMP when spiked in fresh blood and stored at 4 degrees C for 1 week and stored in water over a time period of 10 months. Looking for the stable metabolites like DMP in cases of suspected OP intoxication is recommended.
authors.affiliation: Institute of Legal Medicine, Heinrich-Heine-University, P.O. Box 10 10 07, D-40001 Duesseldorf, Germany.
authors.forename: F A
authors.initials: FA
authors.lastname: Tarbah
authors.forename: B
authors.initials: B
authors.lastname: Kardel
authors.forename: S
authors.initials: S
authors.lastname: Pier
authors.forename: O
authors.initials: O
authors.lastname: Temme
authors.forename: T
authors.initials: T
authors.lastname: Daldrup
mesh_terms: D000328:Adult; D004355:Drug Stability; D005260:Female; D005464:Fluorobenzenes / Q000592:standards; D008401:Gas Chromatography-Mass Spectrometry / Q000295:instrumentation / Q000379:methods / Q000592:standards; D005766:Gastrointestinal Contents / Q000737:chemistry*; D006801:Humans; D007306:Insecticides / Q000032:analysis / Q000506:poisoning*; D009943:Organophosphorus Compounds / Q000032:analysis* / Q000097:blood / Q000652:urine; D010707:Phosphamidon / Q000097:blood / Q000378:metabolism / Q000506:poisoning*; D015203:Reproducibility of Results; D013406:Suicide, Attempted; D013997:Time Factors; D005466:Fluorocarbons
chemical_list: D005464:Fluorobenzenes; D007306:Insecticides; D009943:Organophosphorus Compounds; D010707:Phosphamidon; C025063:pentafluorobenzyl bromide; D005466:Fluorocarbons; C007477:dimethyl phosphate