Entwicklung von Bestimmungs-Methoden fuer NBL-spezifische Pflanzenschutzmittel. T. A: Einsatz der HPLC/MS-Technik und ihre Erprobung an aquatischen Umweltproben des Bezirks Leipzig Abschlussbericht

Within the research project an HPLC/MC coupling with thermospray ionization was used to determine pesticides in aqueous samples with emphasis on pesticides typical for the new German states. The thermospray technique has been applied successfully to 152 agents. A multiresidue method for the determination of 115 agents by HPLC/MS was developed and validated. Using the method of 'selected ion monitoring' absolute detection limits ranging from 0.03 - 1.9 ng were achieved. The linearity of the method is > 10"4, the precision < 10%. The method may be applied equally well for volatile pesticides (also amenable to GC) and thermally labile pesticides (typical analysed by HPLC). The selectivity of the method is significantly higher than that of standard HPLC methods for pesticide analysis. Furthermore, an 'on-line' solid phase enrichment technique was developed. With this technique 50 ml of the aqueous sample are passed through a cartridge with 50 mg of RP-18' adsorbent. The agents retained on the enrichment column are eluted using the initial gradient of the mobile phase and transferred via a six-port-valve onto the analytical column and determined by HPLC/MS. The recoveries of 50 pesticides are > 70% in most instances, while the detection limits of the overall method varies from 1 - 30 ng/l (depending on the compound). The method was used to identify and quantify a variety of pesticides (mainly triazines and phenylureas) in a river Rhine water sample, in ground water samples near the river Rhine and ground water samples near Leipzig. These wells are used as raw water for drinking water production. (orig.)Available from TIB Hannover: F94B2059 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Forschung und Technologie (BMFT), Bonn (Germany)DEGerman