title: The Measurement of Stable Carbon Isotope Ratios of Eight Methamidophos Samples.
abstract: Between December 2007 and January 2008, people suffered from food poisoning in the Japanese prefectures of Chiba and Hyogo after eating frozen dumplings (gyoza) produced in China, which had very high concentrations (1490-19,290 ppm) of methamidophos (O,S-dimethyl phosphoramidothioate). Thus, we measured the stable carbon isotope ratio of methamidophos using GC/C/IRMS to identify the source. We analyzed seven methamidophos reagents and one Chinese agricultural methamidophos chemical (MTD600) that contained many impurities. The δ13C values of the seven methamidophos reagents and MTD600 ranged from -49.23‰ to -31.90‰, with an average SD of 0.20‰, very high precision. This difference (17.33‰) was very large compared with that in previous reports and may be attributable to the material itself and the chemical processing of methamidophos. Criminals can easily obtain pesticides such as methamidophos; therefore, it is very important to identify the pesticide source and distribution route using stable isotopic science in the future.
authors.affiliation: Department of Management Science and Engineering, Faculty of Systems Science and Technology, Akita Prefectural University, 84-4 Ebinokuchi, Tsuchiya, Yurihonjo City, Akita Prefecture, Japan.
authors.forename: Hiroto
authors.initials: H
authors.lastname: Kawashima
mesh_terms: D002247:Carbon Isotopes / Q000032:analysis*; D005517:Foodborne Diseases; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006801:Humans; D007202:Indicators and Reagents; D007306:Insecticides / Q000737:chemistry*; D007564:Japan; D009946:Organothiophosphorus Compounds / Q000737:chemistry*
chemical_list: D002247:Carbon Isotopes; D007202:Indicators and Reagents; D007306:Insecticides; D009946:Organothiophosphorus Compounds; C014655:methamidophos
keywords: compound-specific isotope analysis; food poisoning; food terrorism; forensic science; gas chromatography-mass spectrometry/combustion/isotope ratio mass spectrometry; organophosphorus compound; pesticide; profiling