Entwicklung von Bestimmungsmethoden fuer NBL-spezifische Pflanzenschutzmittel. T. A: Entwicklung von Anreicherungsmethoden und Bestimmungsverfahren auf der Basis der Festphasenextraktion und Kapillar-GC-Technik Abschlussbericht

Abstract

Analytical techniques were developed for the determination of specific plant protectives. These are substances which were permitted only in the former German Democratic Republic and which cannot be analyzed according to DIN 38407. In terms of analysis and methodology, the project focused on the development and improvement of GC-internal and GC-external enrichment processes. Within the possibilities of GC-internal analyte concentration, the injection of large-volume samples by means of PTV systematically investigated. The principle is based on the venting of water in the form of steam before the capillary column, the sorption of the analytes in the PTV-insert and subsequent thermodesorption. In principle, the method allows a larger number of plant protectives to be dealth with simultaneously, including such substances for which standardized techniques are already available. By menas of ECD, NPD or MS (SIM) detection it is possible to achieve detection limits of up to 0.01 #mu#g/l. Furthermore, PTV can be made use of as ractor for the production of volatile species from nonvolatile analytes (Buminafos, Chlormequat). Likewise, analytes can be enriched from large volumes of gaseous samples as in the case of the indirect determination of Ethephon. For a number of agents such as Methamidiphos, Trichlorfon, Butonat, Buminafos, Aldimorph and organomercury compounds, conditions were optimized for the GC-external solid-phase or liquid-liquid extraction, respectively. For this purpose, also the newly developed highly active adsorbent resin, LiChrolut EN, was used. For some agents quite specific methods were developed which are based on reaction-headspace GC (Chloral-derivatives, Ethephon). The analytical techniques developed were used for the examination of 20 raw water samples from the drinking water catchment areas of Leipzig and Halle. Only the persistent triazines and hexachlorbenzene were determined in some samples. (orig.)SIGLEAvailable from TIB Hannover: F95B1225+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman