LC-MS determination of oxydemeton-methyl and its main metabolite demeton-S-methylsulfon in biological specimens--application to a forensic case.
A sensitive method for the identification and quantitation of the organophosphate insecticide oxydemeton-methyl and its metabolite demeton-S-methylsulfon from human blood and various tissue samples has been established. After solid-phase extraction using C18 cartridges the extracts were analyzed by high-performance liquid chromatography with mass selective detection (Finnigan MAT LCQ). The method was completely validated. The limit of detection is 1 ng/g blood for the parent substance oxydemeton-methyl and 2 ng/g blood for the metabolite demeton-S-methylsulfon. This method was applied for the analysis of blood and tissue samples of a 58-year-old man who died after the intake of Metasystox R-Spezial, a product from Bayer containing oxydemeton-methyl. Because of a prolonged interval between the ingestion and death, the concentrations of oxydemeton-methyl and demeton-S-methylsulfon were very low. Although the body was already putrefied when the autopsy was performed, the chromatograms of blood and tissue samples were free of interfering peaks.
Beike
J
J
Institute of Legal Medicine, University Hospital Münster, Germany. beikej@uni-muenster.de
Ortmann
Ch
Ch
Meiners
Th
T
Brinkmann
B
B
Köhler
H
H
D001344:Autopsy; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D062787:Drug Overdose / Q000175:diagnosis; D005554:Forensic Medicine / Q000379:methods; D006801:Humans; D007306:Insecticides / Q000032:analysis / Q000097:blood*; D008297:Male; D013058:Mass Spectrometry / Q000379:methods; D008875:Middle Aged; D009946:Organothiophosphorus Compounds / Q000032:analysis / Q000097:blood* / Q000378:metabolism; D013405:Suicide
D007306:Insecticides; D009946:Organothiophosphorus Compounds; C026086:methyl demeton